Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

19 files changed, 4388 insertions, 0 deletions

diff --git a/third_party/rust/glean-core/tests/boolean.rs b/third_party/rust/glean-core/tests/boolean.rs
new file mode 100644
index 0000000000..0215dd75ec
--- /dev/null
+++ b/third_party/rust/glean-core/tests/boolean.rs
@@ -0,0 +1,91 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{CommonMetricData, Lifetime};
+
+// SKIPPED from glean-ac: string deserializer should correctly parse integers
+// This test doesn't really apply to rkv
+
+#[test]
+fn boolean_serializer_should_correctly_serialize_boolean() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = BooleanMetric::new(CommonMetricData {
+            name: "boolean_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.set_sync(&glean, true);
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"boolean": {"telemetry.boolean_metric": true}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"boolean": {"telemetry.boolean_metric": true}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = BooleanMetric::new(CommonMetricData {
+        name: "boolean_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, true);
+
+    // Check that the data was correctly set in each store.
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"boolean": {"telemetry.boolean_metric": true}}),
+            snapshot
+        );
+    }
+}
+
+// SKIPPED from glean-ac: booleans are serialized in the correct JSON format
+// Completely redundant with other tests.
diff --git a/third_party/rust/glean-core/tests/common/mod.rs b/third_party/rust/glean-core/tests/common/mod.rs
new file mode 100644
index 0000000000..34072b0389
--- /dev/null
+++ b/third_party/rust/glean-core/tests/common/mod.rs
@@ -0,0 +1,145 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+// #[allow(dead_code)] is required on this module as a workaround for
+// https://github.com/rust-lang/rust/issues/46379
+#![allow(dead_code)]
+use glean_core::{Glean, Result};
+
+use std::fs::{read_dir, File};
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+
+use chrono::offset::TimeZone;
+use iso8601::Date::YMD;
+use serde_json::Value as JsonValue;
+
+use ctor::ctor;
+
+/// Initialize the logger for all tests without individual tests requiring to call the init code.
+/// Log output can be controlled via the environment variable `RUST_LOG` for the `glean_core` crate,
+/// e.g.:
+///
+/// ```
+/// export RUST_LOG=glean_core=debug
+/// ```
+#[ctor]
+fn enable_test_logging() {
+    // When testing we want all logs to go to stdout/stderr by default,
+    // without requiring each individual test to activate it.
+    // This only applies to glean-core tests, users of the main library still need to call
+    // `glean_enable_logging` of the FFI component (automatically done by the platform wrappers).
+    let _ = env_logger::builder().is_test(true).try_init();
+}
+
+pub fn tempdir() -> (tempfile::TempDir, String) {
+    let t = tempfile::tempdir().unwrap();
+    let name = t.path().display().to_string();
+    (t, name)
+}
+
+pub const GLOBAL_APPLICATION_ID: &str = "org.mozilla.glean.test.app";
+
+// Creates a new instance of Glean with a temporary directory.
+// We need to keep the `TempDir` alive, so that it's not deleted before we stop using it.
+pub fn new_glean(tempdir: Option<tempfile::TempDir>) -> (Glean, tempfile::TempDir) {
+    let dir = match tempdir {
+        Some(tempdir) => tempdir,
+        None => tempfile::tempdir().unwrap(),
+    };
+
+    let cfg = glean_core::InternalConfiguration {
+        data_path: dir.path().display().to_string(),
+        application_id: GLOBAL_APPLICATION_ID.into(),
+        language_binding_name: "Rust".into(),
+        upload_enabled: true,
+        max_events: None,
+        delay_ping_lifetime_io: false,
+        app_build: "Unknown".into(),
+        use_core_mps: false,
+        trim_data_to_registered_pings: false,
+        log_level: None,
+    };
+    let glean = Glean::new(cfg).unwrap();
+
+    (glean, dir)
+}
+
+/// Converts an iso8601::DateTime to a chrono::DateTime<FixedOffset>
+pub fn iso8601_to_chrono(datetime: &iso8601::DateTime) -> chrono::DateTime<chrono::FixedOffset> {
+    if let YMD { year, month, day } = datetime.date {
+        return chrono::FixedOffset::east(datetime.time.tz_offset_hours * 3600)
+            .ymd(year, month, day)
+            .and_hms_milli(
+                datetime.time.hour,
+                datetime.time.minute,
+                datetime.time.second,
+                datetime.time.millisecond,
+            );
+    };
+    panic!("Unsupported datetime format");
+}
+
+/// Gets a vector of the currently queued pings.
+///
+/// # Arguments
+///
+/// * `data_path` - Glean's data path, as returned from Glean::get_data_path()
+///
+/// # Returns
+///
+/// A vector of all queued pings.
+///
+/// Each entry is a pair `(url, json_data, metadata)`,
+/// where `url` is the endpoint the ping will go to, `json_data` is the JSON payload
+/// and metadata is optional persisted data related to the ping.
+pub fn get_queued_pings(data_path: &Path) -> Result<Vec<(String, JsonValue, Option<JsonValue>)>> {
+    get_pings(&data_path.join("pending_pings"))
+}
+
+/// Gets a vector of the currently queued `deletion-request` pings.
+///
+/// # Arguments
+///
+/// * `data_path` - Glean's data path, as returned from Glean::get_data_path()
+///
+/// # Returns
+///
+/// A vector of all queued pings.
+///
+/// Each entry is a pair `(url, json_data, metadata)`,
+/// where `url` is the endpoint the ping will go to, `json_data` is the JSON payload
+/// and metadata is optional persisted data related to the ping.
+pub fn get_deletion_pings(data_path: &Path) -> Result<Vec<(String, JsonValue, Option<JsonValue>)>> {
+    get_pings(&data_path.join("deletion_request"))
+}
+
+fn get_pings(pings_dir: &Path) -> Result<Vec<(String, JsonValue, Option<JsonValue>)>> {
+    let entries = read_dir(pings_dir)?;
+    Ok(entries
+        .filter_map(|entry| entry.ok())
+        .filter(|entry| match entry.file_type() {
+            Ok(file_type) => file_type.is_file(),
+            Err(_) => false,
+        })
+        .filter_map(|entry| File::open(entry.path()).ok())
+        .filter_map(|file| {
+            let mut lines = BufReader::new(file).lines();
+            if let (Some(Ok(url)), Some(Ok(body)), Ok(metadata)) =
+                (lines.next(), lines.next(), lines.next().transpose())
+            {
+                let parsed_metadata = metadata.map(|m| {
+                    serde_json::from_str::<JsonValue>(&m).expect("metadata should be valid JSON")
+                });
+                if let Ok(parsed_body) = serde_json::from_str::<JsonValue>(&body) {
+                    Some((url, parsed_body, parsed_metadata))
+                } else {
+                    None
+                }
+            } else {
+                None
+            }
+        })
+        .collect())
+}
diff --git a/third_party/rust/glean-core/tests/counter.rs b/third_party/rust/glean-core/tests/counter.rs
new file mode 100644
index 0000000000..0a720a696e
--- /dev/null
+++ b/third_party/rust/glean-core/tests/counter.rs
@@ -0,0 +1,177 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+// SKIPPED from glean-ac: counter deserializer should correctly parse integers
+// This test doesn't really apply to rkv
+
+#[test]
+fn counter_serializer_should_correctly_serialize_counters() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = CounterMetric::new(CommonMetricData {
+            name: "counter_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.add_sync(&glean, 1);
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"counter": {"telemetry.counter_metric": 1}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"counter": {"telemetry.counter_metric": 1}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_value_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = CounterMetric::new(CommonMetricData {
+        name: "counter_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.add_sync(&glean, 1);
+
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"counter": {"telemetry.counter_metric": 1}}),
+            snapshot
+        );
+    }
+}
+
+// SKIPPED from glean-ac: counters are serialized in the correct JSON format
+// Completely redundant with other tests.
+
+#[test]
+fn counters_must_not_increment_when_passed_zero_or_negative() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = CounterMetric::new(CommonMetricData {
+        name: "counter_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Application,
+        ..Default::default()
+    });
+
+    // Attempt to increment the counter with zero
+    metric.add_sync(&glean, 0);
+    // Check that nothing was recorded
+    assert!(metric.get_value(&glean, Some("store1")).is_none());
+
+    // Attempt to increment the counter with negative
+    metric.add_sync(&glean, -1);
+    // Check that nothing was recorded
+    assert!(metric.get_value(&glean, Some("store1")).is_none());
+
+    // Attempt increment counter properly
+    metric.add_sync(&glean, 1);
+    // Check that nothing was recorded
+    assert_eq!(1, metric.get_value(&glean, Some("store1")).unwrap());
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(2),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
+
+// New tests for glean-core below
+
+#[test]
+fn transformation_works() {
+    let (glean, _t) = new_glean(None);
+
+    let counter: CounterMetric = CounterMetric::new(CommonMetricData {
+        name: "transformation".into(),
+        category: "local".into(),
+        send_in_pings: vec!["store1".into(), "store2".into()],
+        ..Default::default()
+    });
+
+    counter.add_sync(&glean, 2);
+
+    assert_eq!(2, counter.get_value(&glean, Some("store1")).unwrap());
+    assert_eq!(2, counter.get_value(&glean, Some("store2")).unwrap());
+
+    // Clearing just one store
+    let _ = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    counter.add_sync(&glean, 2);
+
+    assert_eq!(2, counter.get_value(&glean, Some("store1")).unwrap());
+    assert_eq!(4, counter.get_value(&glean, Some("store2")).unwrap());
+}
+
+#[test]
+fn saturates_at_boundary() {
+    let (glean, _t) = new_glean(None);
+
+    let counter: CounterMetric = CounterMetric::new(CommonMetricData {
+        name: "transformation".into(),
+        category: "local".into(),
+        send_in_pings: vec!["store1".into()],
+        ..Default::default()
+    });
+
+    counter.add_sync(&glean, 2);
+    counter.add_sync(&glean, i32::max_value());
+
+    assert_eq!(
+        i32::max_value(),
+        counter.get_value(&glean, Some("store1")).unwrap()
+    );
+}
diff --git a/third_party/rust/glean-core/tests/custom_distribution.rs b/third_party/rust/glean-core/tests/custom_distribution.rs
new file mode 100644
index 0000000000..43c69fb26d
--- /dev/null
+++ b/third_party/rust/glean-core/tests/custom_distribution.rs
@@ -0,0 +1,419 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+mod linear {
+    use super::*;
+
+    #[test]
+    fn serializer_should_correctly_serialize_custom_distribution() {
+        let (mut tempdir, _) = tempdir();
+
+        {
+            let (glean, dir) = new_glean(Some(tempdir));
+            tempdir = dir;
+
+            let metric = CustomDistributionMetric::new(
+                CommonMetricData {
+                    name: "distribution".into(),
+                    category: "telemetry".into(),
+                    send_in_pings: vec!["store1".into()],
+                    disabled: false,
+                    lifetime: Lifetime::Ping,
+                    ..Default::default()
+                },
+                1,
+                100,
+                100,
+                HistogramType::Linear,
+            );
+
+            metric.accumulate_samples_sync(&glean, vec![50]);
+
+            let snapshot = metric
+                .get_value(&glean, "store1")
+                .expect("Value should be stored");
+
+            assert_eq!(snapshot.sum, 50);
+        }
+
+        // Make a new Glean instance here, which should force reloading of the data from disk
+        // so we can ensure it persisted, because it has User lifetime
+        {
+            let (glean, _t) = new_glean(Some(tempdir));
+            let snapshot = StorageManager
+                .snapshot_as_json(glean.storage(), "store1", true)
+                .unwrap();
+
+            assert_eq!(
+                json!(50),
+                snapshot["custom_distribution"]["telemetry.distribution"]["sum"]
+            );
+        }
+    }
+
+    #[test]
+    fn set_value_properly_sets_the_value_in_all_stores() {
+        let (glean, _t) = new_glean(None);
+        let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: store_names.clone(),
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            100,
+            HistogramType::Linear,
+        );
+
+        metric.accumulate_samples_sync(&glean, vec![50]);
+
+        for store_name in store_names {
+            let snapshot = StorageManager
+                .snapshot_as_json(glean.storage(), &store_name, true)
+                .unwrap();
+
+            assert_eq!(
+                json!(50),
+                snapshot["custom_distribution"]["telemetry.distribution"]["sum"]
+            );
+            assert_eq!(
+                json!(1),
+                snapshot["custom_distribution"]["telemetry.distribution"]["values"]["50"]
+            );
+        }
+    }
+
+    // SKIPPED from glean-ac: memory distributions must not accumulate negative values
+    // This test doesn't apply to Rust, because we're using unsigned integers.
+
+    #[test]
+    fn the_accumulate_samples_api_correctly_stores_memory_values() {
+        let (glean, _t) = new_glean(None);
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            100,
+            HistogramType::Linear,
+        );
+
+        // Accumulate the samples. We intentionally do not report
+        // negative values to not trigger error reporting.
+        metric.accumulate_samples_sync(&glean, [1, 2, 3].to_vec());
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        // Check that we got the right sum of samples.
+        assert_eq!(snapshot.sum, 6);
+
+        // We should get a sample in 3 buckets.
+        // These numbers are a bit magic, but they correspond to
+        // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+        assert_eq!(1, snapshot.values[&1]);
+        assert_eq!(1, snapshot.values[&2]);
+        assert_eq!(1, snapshot.values[&3]);
+
+        // No errors should be reported.
+        assert!(
+            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err()
+        );
+    }
+
+    #[test]
+    fn the_accumulate_samples_api_correctly_handles_negative_values() {
+        let (glean, _t) = new_glean(None);
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            100,
+            HistogramType::Linear,
+        );
+
+        // Accumulate the samples.
+        metric.accumulate_samples_sync(&glean, [-1, 1, 2, 3].to_vec());
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        // Check that we got the right sum of samples.
+        assert_eq!(snapshot.sum, 6);
+
+        // We should get a sample in 3 buckets.
+        // These numbers are a bit magic, but they correspond to
+        // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+        assert_eq!(1, snapshot.values[&1]);
+        assert_eq!(1, snapshot.values[&2]);
+        assert_eq!(1, snapshot.values[&3]);
+
+        // 1 error should be reported.
+        assert_eq!(
+            Ok(1),
+            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+        );
+    }
+
+    #[test]
+    fn json_snapshotting_works() {
+        let (glean, _t) = new_glean(None);
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            100,
+            HistogramType::Linear,
+        );
+
+        metric.accumulate_samples_sync(&glean, vec![50]);
+
+        let snapshot = metric.get_value(&glean, "store1");
+        assert!(snapshot.is_some());
+    }
+}
+
+mod exponential {
+    use super::*;
+
+    #[test]
+    fn serializer_should_correctly_serialize_custom_distribution() {
+        let (mut tempdir, _) = tempdir();
+
+        {
+            let (glean, dir) = new_glean(Some(tempdir));
+            tempdir = dir;
+
+            let metric = CustomDistributionMetric::new(
+                CommonMetricData {
+                    name: "distribution".into(),
+                    category: "telemetry".into(),
+                    send_in_pings: vec!["store1".into()],
+                    disabled: false,
+                    lifetime: Lifetime::Ping,
+                    ..Default::default()
+                },
+                1,
+                100,
+                10,
+                HistogramType::Exponential,
+            );
+
+            metric.accumulate_samples_sync(&glean, vec![50]);
+
+            let snapshot = metric
+                .get_value(&glean, "store1")
+                .expect("Value should be stored");
+
+            assert_eq!(snapshot.sum, 50);
+        }
+
+        // Make a new Glean instance here, which should force reloading of the data from disk
+        // so we can ensure it persisted, because it has User lifetime
+        {
+            let (glean, _t) = new_glean(Some(tempdir));
+            let snapshot = StorageManager
+                .snapshot_as_json(glean.storage(), "store1", true)
+                .unwrap();
+
+            assert_eq!(
+                json!(50),
+                snapshot["custom_distribution"]["telemetry.distribution"]["sum"]
+            );
+        }
+    }
+
+    #[test]
+    fn set_value_properly_sets_the_value_in_all_stores() {
+        let (glean, _t) = new_glean(None);
+        let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: store_names.clone(),
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            10,
+            HistogramType::Exponential,
+        );
+
+        metric.accumulate_samples_sync(&glean, vec![50]);
+
+        for store_name in store_names {
+            let snapshot = StorageManager
+                .snapshot_as_json(glean.storage(), &store_name, true)
+                .unwrap();
+
+            assert_eq!(
+                json!(50),
+                snapshot["custom_distribution"]["telemetry.distribution"]["sum"]
+            );
+            assert_eq!(
+                json!(1),
+                snapshot["custom_distribution"]["telemetry.distribution"]["values"]["29"]
+            );
+        }
+    }
+
+    // SKIPPED from glean-ac: memory distributions must not accumulate negative values
+    // This test doesn't apply to Rust, because we're using unsigned integers.
+
+    #[test]
+    fn the_accumulate_samples_api_correctly_stores_memory_values() {
+        let (glean, _t) = new_glean(None);
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            10,
+            HistogramType::Exponential,
+        );
+
+        // Accumulate the samples. We intentionally do not report
+        // negative values to not trigger error reporting.
+        metric.accumulate_samples_sync(&glean, [1, 2, 3].to_vec());
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        // Check that we got the right sum of samples.
+        assert_eq!(snapshot.sum, 6);
+
+        // We should get a sample in 3 buckets.
+        // These numbers are a bit magic, but they correspond to
+        // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+        assert_eq!(1, snapshot.values[&1]);
+        assert_eq!(1, snapshot.values[&2]);
+        assert_eq!(1, snapshot.values[&3]);
+
+        // No errors should be reported.
+        assert!(
+            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err()
+        );
+    }
+
+    #[test]
+    fn the_accumulate_samples_api_correctly_handles_negative_values() {
+        let (glean, _t) = new_glean(None);
+
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            10,
+            HistogramType::Exponential,
+        );
+
+        // Accumulate the samples.
+        metric.accumulate_samples_sync(&glean, [-1, 1, 2, 3].to_vec());
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        // Check that we got the right sum of samples.
+        assert_eq!(snapshot.sum, 6);
+
+        // We should get a sample in 3 buckets.
+        // These numbers are a bit magic, but they correspond to
+        // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+        assert_eq!(1, snapshot.values[&1]);
+        assert_eq!(1, snapshot.values[&2]);
+        assert_eq!(1, snapshot.values[&3]);
+
+        // 1 error should be reported.
+        assert_eq!(
+            Ok(1),
+            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+        );
+    }
+
+    #[test]
+    fn json_snapshotting_works() {
+        let (glean, _t) = new_glean(None);
+        let metric = CustomDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            1,
+            100,
+            10,
+            HistogramType::Exponential,
+        );
+
+        metric.accumulate_samples_sync(&glean, vec![50]);
+
+        let snapshot = metric.get_value(&glean, "store1");
+        assert!(snapshot.is_some());
+    }
+}
diff --git a/third_party/rust/glean-core/tests/datetime.rs b/third_party/rust/glean-core/tests/datetime.rs
new file mode 100644
index 0000000000..7e7938690f
--- /dev/null
+++ b/third_party/rust/glean-core/tests/datetime.rs
@@ -0,0 +1,187 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use chrono::prelude::*;
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{CommonMetricData, Lifetime};
+
+// SKIPPED from glean-ac: datetime deserializer should correctly parse integers
+// This test doesn't really apply to rkv
+
+#[test]
+fn datetime_serializer_should_correctly_serialize_datetime() {
+    let expected_value = "1983-04-13T12:09+00:00";
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = DatetimeMetric::new(
+            CommonMetricData {
+                name: "datetime_metric".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::User,
+                ..Default::default()
+            },
+            TimeUnit::Minute,
+        );
+
+        // `1983-04-13T12:09:14.274+00:00` will be truncated to Minute resolution.
+        let dt = FixedOffset::east(0)
+            .ymd(1983, 4, 13)
+            .and_hms_milli(12, 9, 14, 274);
+        metric.set_sync(&glean, Some(dt.into()));
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"datetime": {"telemetry.datetime_metric": expected_value}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"datetime": {"telemetry.datetime_metric": expected_value}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_value_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = DatetimeMetric::new(
+        CommonMetricData {
+            name: "datetime_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names.clone(),
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    // `1983-04-13T12:09:14.274+00:00` will be truncated to Minute resolution.
+    let dt = FixedOffset::east(0)
+        .ymd(1983, 4, 13)
+        .and_hms_nano(12, 9, 14, 1_560_274);
+    metric.set_sync(&glean, Some(dt.into()));
+
+    for store_name in store_names {
+        assert_eq!(
+            "1983-04-13T12:09:14.001560274+00:00",
+            metric
+                .get_value_as_string(&glean, Some(store_name))
+                .unwrap()
+        );
+    }
+}
+
+// SKIPPED from glean-ac: getSnapshot() returns null if nothing is recorded in the store
+// This test doesn't really apply to rkv
+
+// SKIPPED from glean-ac: getSnapshot() correctly clears the stores
+// This test doesn't really apply to rkv
+
+#[test]
+fn test_that_truncation_works() {
+    let (glean, _t) = new_glean(None);
+
+    // `1985-07-03T12:09:14.000560274+01:00`
+    let high_res_datetime = FixedOffset::east(3600)
+        .ymd(1985, 7, 3)
+        .and_hms_nano(12, 9, 14, 1_560_274);
+    let store_name = "store1";
+
+    // Create an helper struct for defining the truncation cases.
+    struct TestCase {
+        case_name: &'static str,
+        desired_resolution: TimeUnit,
+        expected_result: &'static str,
+    }
+
+    // Define the single test cases.
+    let test_cases = vec![
+        TestCase {
+            case_name: "nano",
+            desired_resolution: TimeUnit::Nanosecond,
+            expected_result: "1985-07-03T12:09:14.001560274+01:00",
+        },
+        TestCase {
+            case_name: "micro",
+            desired_resolution: TimeUnit::Microsecond,
+            expected_result: "1985-07-03T12:09:14.001560+01:00",
+        },
+        TestCase {
+            case_name: "milli",
+            desired_resolution: TimeUnit::Millisecond,
+            expected_result: "1985-07-03T12:09:14.001+01:00",
+        },
+        TestCase {
+            case_name: "second",
+            desired_resolution: TimeUnit::Second,
+            expected_result: "1985-07-03T12:09:14+01:00",
+        },
+        TestCase {
+            case_name: "minute",
+            desired_resolution: TimeUnit::Minute,
+            expected_result: "1985-07-03T12:09+01:00",
+        },
+        TestCase {
+            case_name: "hour",
+            desired_resolution: TimeUnit::Hour,
+            expected_result: "1985-07-03T12+01:00",
+        },
+        TestCase {
+            case_name: "day",
+            desired_resolution: TimeUnit::Day,
+            expected_result: "1985-07-03+01:00",
+        },
+    ];
+
+    // Execute them all.
+    for t in test_cases {
+        let metric = DatetimeMetric::new(
+            CommonMetricData {
+                name: format!("datetime_metric_{}", t.case_name),
+                category: "telemetry".into(),
+                send_in_pings: vec![store_name.into()],
+                disabled: false,
+                lifetime: Lifetime::User,
+                ..Default::default()
+            },
+            t.desired_resolution,
+        );
+        metric.set_sync(&glean, Some(high_res_datetime.into()));
+
+        assert_eq!(
+            t.expected_result,
+            metric
+                .get_value_as_string(&glean, Some(store_name.into()))
+                .unwrap()
+        );
+    }
+}
diff --git a/third_party/rust/glean-core/tests/event.rs b/third_party/rust/glean-core/tests/event.rs
new file mode 100644
index 0000000000..1773a5f4e5
--- /dev/null
+++ b/third_party/rust/glean-core/tests/event.rs
@@ -0,0 +1,454 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use std::collections::HashMap;
+use std::fs;
+
+use glean_core::metrics::*;
+use glean_core::{
+    get_timestamp_ms, test_get_num_recorded_errors, CommonMetricData, ErrorType, Lifetime,
+};
+
+#[test]
+fn record_properly_records_without_optional_arguments() {
+    let store_names = vec!["store1".into(), "store2".into()];
+
+    let (glean, _t) = new_glean(None);
+
+    let metric = EventMetric::new(
+        CommonMetricData {
+            name: "test_event_no_optional".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names.clone(),
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec![],
+    );
+
+    metric.record_sync(&glean, 1000, HashMap::new());
+
+    for store_name in store_names {
+        let events = metric.get_value(&glean, &*store_name).unwrap();
+        assert_eq!(1, events.len());
+        assert_eq!("telemetry", events[0].category);
+        assert_eq!("test_event_no_optional", events[0].name);
+        assert!(events[0].extra.is_none());
+    }
+}
+
+#[test]
+fn record_properly_records_with_optional_arguments() {
+    let (glean, _t) = new_glean(None);
+
+    let store_names = vec!["store1".into(), "store2".into()];
+
+    let metric = EventMetric::new(
+        CommonMetricData {
+            name: "test_event_no_optional".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names.clone(),
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec!["key1".into(), "key2".into()],
+    );
+
+    let extra = [
+        ("key1".into(), "value1".into()),
+        ("key2".into(), "value2".into()),
+    ]
+    .iter()
+    .cloned()
+    .collect();
+
+    metric.record_sync(&glean, 1000, extra);
+
+    for store_name in store_names {
+        let events = metric.get_value(&glean, &*store_name).unwrap();
+        let event = events[0].clone();
+        assert_eq!(1, events.len());
+        assert_eq!("telemetry", event.category);
+        assert_eq!("test_event_no_optional", event.name);
+        let extra = event.extra.unwrap();
+        assert_eq!(2, extra.len());
+        assert_eq!("value1", extra["key1"]);
+        assert_eq!("value2", extra["key2"]);
+    }
+}
+
+// SKIPPED record() computes the correct time between events
+// Timing is now handled in the language-specific part.
+
+#[test]
+fn snapshot_returns_none_if_nothing_is_recorded_in_the_store() {
+    let (glean, _t) = new_glean(None);
+
+    assert!(glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store1", false)
+        .is_none())
+}
+
+#[test]
+fn snapshot_correctly_clears_the_stores() {
+    let (glean, _t) = new_glean(None);
+
+    let store_names = vec!["store1".into(), "store2".into()];
+
+    let metric = EventMetric::new(
+        CommonMetricData {
+            name: "test_event_clear".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names,
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec![],
+    );
+
+    metric.record_sync(&glean, 1000, HashMap::new());
+
+    let snapshot = glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store1", true);
+    assert!(snapshot.is_some());
+
+    assert!(glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store1", false)
+        .is_none());
+
+    let files: Vec<fs::DirEntry> = fs::read_dir(&glean.event_storage().path)
+        .unwrap()
+        .filter_map(|x| x.ok())
+        .collect();
+    assert_eq!(1, files.len());
+    assert_eq!("store2", files[0].file_name());
+
+    let snapshot2 = glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store2", false);
+    for s in vec![snapshot, snapshot2] {
+        assert!(s.is_some());
+        let s = s.unwrap();
+        assert_eq!(1, s.as_array().unwrap().len());
+        assert_eq!("telemetry", s[0]["category"]);
+        assert_eq!("test_event_clear", s[0]["name"]);
+        println!("{:?}", s[0].get("extra"));
+        assert!(s[0].get("extra").is_none());
+    }
+}
+
+// SKIPPED: Events are serialized in the correct JSON format (no extra)
+// SKIPPED: Events are serialized in the correct JSON format (with extra)
+// This test won't work as-is since Rust doesn't maintain the insertion order in
+// a JSON object, therefore you can't check the JSON output directly against a
+// string.  This check is redundant with other tests, anyway, and checking against
+// the schema is much more useful.
+
+#[test]
+fn test_sending_of_event_ping_when_it_fills_up() {
+    let (mut glean, _t) = new_glean(None);
+
+    let store_names: Vec<String> = vec!["events".into()];
+
+    for store_name in &store_names {
+        glean.register_ping_type(&PingType::new(
+            store_name.clone(),
+            true,
+            false,
+            vec!["max_capacity".to_string()],
+        ));
+    }
+
+    let click = EventMetric::new(
+        CommonMetricData {
+            name: "click".into(),
+            category: "ui".into(),
+            send_in_pings: store_names,
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec!["test_event_number".into()],
+    );
+
+    // We send 510 events. We expect to get the first 500 in the ping and 10
+    // remaining afterward
+    for i in 0..510 {
+        let mut extra = HashMap::new();
+        extra.insert("test_event_number".to_string(), i.to_string());
+        click.record_sync(&glean, i, extra);
+    }
+
+    assert_eq!(10, click.get_value(&glean, "events").unwrap().len());
+
+    let (url, json, _) = &get_queued_pings(glean.get_data_path()).unwrap()[0];
+    assert!(url.starts_with(format!("/submit/{}/events/", glean.get_application_id()).as_str()));
+    assert_eq!(500, json["events"].as_array().unwrap().len());
+    assert_eq!(
+        "max_capacity",
+        json["ping_info"].as_object().unwrap()["reason"]
+            .as_str()
+            .unwrap()
+    );
+
+    for i in 0..500 {
+        let event = &json["events"].as_array().unwrap()[i];
+        assert_eq!(i.to_string(), event["extra"]["test_event_number"]);
+    }
+
+    let snapshot = glean
+        .event_storage()
+        .snapshot_as_json(&glean, "events", false)
+        .unwrap();
+    assert_eq!(10, snapshot.as_array().unwrap().len());
+    for i in 0..10 {
+        let event = &snapshot.as_array().unwrap()[i];
+        assert_eq!((i + 500).to_string(), event["extra"]["test_event_number"]);
+    }
+}
+
+#[test]
+fn extra_keys_must_be_recorded_and_truncated_if_needed() {
+    let (glean, _t) = new_glean(None);
+
+    let store_names: Vec<String> = vec!["store1".into()];
+
+    let test_event = EventMetric::new(
+        CommonMetricData {
+            name: "testEvent".into(),
+            category: "ui".into(),
+            send_in_pings: store_names,
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec!["extra1".into(), "truncatedExtra".into()],
+    );
+
+    let test_value = "LeanGleanByFrank";
+    let test_value_long = test_value.to_string().repeat(32);
+    // max length for extra values.
+    let test_value_cap = 500;
+    assert!(
+        test_value_long.len() > test_value_cap,
+        "test value is not long enough"
+    );
+    let mut extra = HashMap::new();
+    extra.insert("extra1".into(), test_value.to_string());
+    extra.insert("truncatedExtra".into(), test_value_long.clone());
+
+    test_event.record_sync(&glean, 0, extra);
+
+    let snapshot = glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store1", false)
+        .unwrap();
+    assert_eq!(1, snapshot.as_array().unwrap().len());
+    let event = &snapshot.as_array().unwrap()[0];
+    assert_eq!("ui", event["category"]);
+    assert_eq!("testEvent", event["name"]);
+    assert_eq!(2, event["extra"].as_object().unwrap().len());
+    assert_eq!(test_value, event["extra"]["extra1"]);
+    assert_eq!(
+        test_value_long[0..test_value_cap],
+        event["extra"]["truncatedExtra"]
+    );
+}
+
+#[test]
+fn snapshot_sorts_the_timestamps() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = EventMetric::new(
+        CommonMetricData {
+            name: "test_event_clear".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec![],
+    );
+
+    metric.record_sync(&glean, 1000, HashMap::new());
+    metric.record_sync(&glean, 100, HashMap::new());
+    metric.record_sync(&glean, 10000, HashMap::new());
+
+    let snapshot = glean
+        .event_storage()
+        .snapshot_as_json(&glean, "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        0,
+        snapshot.as_array().unwrap()[0]["timestamp"]
+            .as_i64()
+            .unwrap()
+    );
+    assert_eq!(
+        900,
+        snapshot.as_array().unwrap()[1]["timestamp"]
+            .as_i64()
+            .unwrap()
+    );
+    assert_eq!(
+        9900,
+        snapshot.as_array().unwrap()[2]["timestamp"]
+            .as_i64()
+            .unwrap()
+    );
+}
+
+#[test]
+fn ensure_custom_ping_events_dont_overflow() {
+    let (glean, _dir) = new_glean(None);
+
+    let store_name = "store-name";
+    let event_meta = CommonMetricData {
+        name: "name".into(),
+        category: "category".into(),
+        send_in_pings: vec![store_name.into()],
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    };
+    let event = EventMetric::new(event_meta.clone(), vec![]);
+
+    assert!(test_get_num_recorded_errors(
+        &glean,
+        &(event_meta.clone()).into(),
+        ErrorType::InvalidOverflow
+    )
+    .is_err());
+
+    for _ in 0..500 {
+        event.record_sync(&glean, 0, HashMap::new());
+    }
+    assert!(test_get_num_recorded_errors(
+        &glean,
+        &(event_meta.clone()).into(),
+        ErrorType::InvalidOverflow
+    )
+    .is_err());
+
+    // That should top us right up to the limit. Now for going over.
+    event.record_sync(&glean, 0, HashMap::new());
+    assert!(
+        test_get_num_recorded_errors(&glean, &event_meta.into(), ErrorType::InvalidOverflow)
+            .is_err()
+    );
+    assert_eq!(501, event.get_value(&glean, store_name).unwrap().len());
+}
+
+/// Ensure that events from multiple runs serialize properly.
+///
+/// Records an event once each in two separate sessions,
+/// ensuring they both show (and an inserted `glean.restarted` event)
+/// in the serialized result.
+#[test]
+fn ensure_custom_ping_events_from_multiple_runs_work() {
+    let (mut tempdir, _) = tempdir();
+
+    let store_name = "store-name";
+    let event = EventMetric::new(
+        CommonMetricData {
+            name: "name".into(),
+            category: "category".into(),
+            send_in_pings: vec![store_name.into()],
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec![],
+    );
+
+    {
+        let (glean, dir) = new_glean(Some(tempdir));
+        // We don't need a full init. Just to deal with on-disk events:
+        assert!(!glean
+            .event_storage()
+            .flush_pending_events_on_startup(&glean, false));
+        tempdir = dir;
+
+        event.record_sync(&glean, 10, HashMap::new());
+    }
+
+    {
+        let (glean, _dir) = new_glean(Some(tempdir));
+        // We don't need a full init. Just to deal with on-disk events:
+        assert!(!glean
+            .event_storage()
+            .flush_pending_events_on_startup(&glean, false));
+
+        // Gotta use get_timestamp_ms or this event won't happen "after" the injected
+        // glean.restarted event from `flush_pending_events_on_startup`.
+        event.record_sync(&glean, get_timestamp_ms(), HashMap::new());
+
+        let json = glean
+            .event_storage()
+            .snapshot_as_json(&glean, store_name, false)
+            .unwrap();
+        assert_eq!(json.as_array().unwrap().len(), 3);
+        assert_eq!(json[0]["category"], "category");
+        assert_eq!(json[0]["name"], "name");
+        assert_eq!(json[1]["category"], "glean");
+        assert_eq!(json[1]["name"], "restarted");
+        assert_eq!(json[2]["category"], "category");
+        assert_eq!(json[2]["name"], "name");
+    }
+}
+
+/// Ensure events in an unregistered, non-"events" (ie Custom) ping are trimmed on a subsequent init
+/// when we pass `true ` for `trim_data_to_registered_pings` in `on_ready_to_submit_pings`.
+#[test]
+fn event_storage_trimming() {
+    let (mut tempdir, _) = tempdir();
+
+    let store_name = "store-name";
+    let store_name_2 = "store-name-2";
+    let event = EventMetric::new(
+        CommonMetricData {
+            name: "name".into(),
+            category: "category".into(),
+            send_in_pings: vec![store_name.into(), store_name_2.into()],
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        vec![],
+    );
+    // First, record the event in the two pings.
+    // Successfully records just fine because nothing's checking on record that these pings
+    // exist and are registered.
+    {
+        let (glean, dir) = new_glean(Some(tempdir));
+        tempdir = dir;
+        event.record_sync(&glean, 10, HashMap::new());
+
+        assert_eq!(1, event.get_value(&glean, store_name).unwrap().len());
+        assert_eq!(1, event.get_value(&glean, store_name_2).unwrap().len());
+    }
+    // Second, construct (but don't init) Glean over again.
+    // Register exactly one of the two pings.
+    // Then process the part of init that does the trimming (`on_ready_to_submit_pings`).
+    // This ought to load the data from the registered ping and trim the data from the unregistered one.
+    {
+        let (mut glean, _dir) = new_glean(Some(tempdir));
+        // In Rust, pings are registered via construction.
+        // But that's done asynchronously, so we do it synchronously here:
+        glean.register_ping_type(&PingType::new(store_name.to_string(), true, false, vec![]));
+
+        glean.on_ready_to_submit_pings(true);
+
+        assert_eq!(1, event.get_value(&glean, store_name).unwrap().len());
+        assert!(event.get_value(&glean, store_name_2).is_none());
+    }
+}
diff --git a/third_party/rust/glean-core/tests/labeled.rs b/third_party/rust/glean-core/tests/labeled.rs
new file mode 100644
index 0000000000..63a7f2ccc2
--- /dev/null
+++ b/third_party/rust/glean-core/tests/labeled.rs
@@ -0,0 +1,518 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+#[test]
+fn can_create_labeled_counter_metric() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        Some(vec!["label1".into()]),
+    );
+
+    let metric = labeled.get("label1");
+    metric.add_sync(&glean, 1);
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "telemetry.labeled_metric": { "label1": 1 }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn can_create_labeled_string_metric() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledString::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        Some(vec!["label1".into()]),
+    );
+
+    let metric = labeled.get("label1");
+    metric.set_sync(&glean, "text");
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_string": {
+                "telemetry.labeled_metric": { "label1": "text" }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn can_create_labeled_bool_metric() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledBoolean::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        Some(vec!["label1".into()]),
+    );
+
+    let metric = labeled.get("label1");
+    metric.set_sync(&glean, true);
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_boolean": {
+                "telemetry.labeled_metric": { "label1": true }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn can_use_multiple_labels() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    let metric = labeled.get("label1");
+    metric.add_sync(&glean, 1);
+
+    let metric = labeled.get("label2");
+    metric.add_sync(&glean, 2);
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "telemetry.labeled_metric": {
+                    "label1": 1,
+                    "label2": 2,
+                }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn can_record_error_for_submetric() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledString::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        Some(vec!["label1".into()]),
+    );
+
+    let metric = labeled.get("label1");
+    metric.set_sync(&glean, "01234567890".repeat(20));
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
+
+#[test]
+fn labels_are_checked_against_static_list() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        Some(vec!["label1".into(), "label2".into()]),
+    );
+
+    let metric = labeled.get("label1");
+    metric.add_sync(&glean, 1);
+
+    let metric = labeled.get("label2");
+    metric.add_sync(&glean, 2);
+
+    // All non-registed labels get mapped to the `other` label
+    let metric = labeled.get("label3");
+    metric.add_sync(&glean, 3);
+    let metric = labeled.get("label4");
+    metric.add_sync(&glean, 4);
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "telemetry.labeled_metric": {
+                    "label1": 1,
+                    "label2": 2,
+                    "__other__": 7,
+                }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn dynamic_labels_too_long() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    let metric = labeled.get("1".repeat(72));
+    metric.add_sync(&glean, 1);
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "glean.error.invalid_label": { "telemetry.labeled_metric": 1 },
+                "telemetry.labeled_metric": {
+                    "__other__": 1,
+                }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn dynamic_labels_regex_mismatch() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    let labels_not_validating = vec!["non-ASCII�"];
+    let num_non_validating = labels_not_validating.len();
+
+    for label in &labels_not_validating {
+        labeled.get(label).add_sync(&glean, 1);
+    }
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "glean.error.invalid_label": { "telemetry.labeled_metric": num_non_validating },
+                "telemetry.labeled_metric": {
+                    "__other__": num_non_validating,
+                }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn dynamic_labels_regex_allowed() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    let labels_validating = vec![
+        "this.is.fine",
+        "this_is_fine_too",
+        "this.is_still_fine",
+        "thisisfine",
+        "_.is_fine",
+        "this.is-fine",
+        "this-is-fine",
+    ];
+
+    for label in &labels_validating {
+        labeled.get(label).add_sync(&glean, 1);
+    }
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    assert_eq!(
+        json!({
+            "labeled_counter": {
+                "telemetry.labeled_metric": {
+                    "this.is.fine": 1,
+                    "this_is_fine_too": 1,
+                    "this.is_still_fine": 1,
+                    "thisisfine": 1,
+                    "_.is_fine": 1,
+                    "this.is-fine": 1,
+                    "this-is-fine": 1
+                }
+            }
+        }),
+        snapshot
+    );
+}
+
+#[test]
+fn seen_labels_get_reloaded_from_disk() {
+    let (mut tempdir, _) = tempdir();
+
+    let (glean, dir) = new_glean(Some(tempdir));
+    tempdir = dir;
+
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "labeled_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    // Store some data into labeled metrics
+    {
+        // Set the maximum number of labels
+        for i in 1..=16 {
+            let label = format!("label{i}");
+            labeled.get(label).add_sync(&glean, i);
+        }
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", false)
+            .unwrap();
+
+        // Check that the data is there
+        for i in 1..=16 {
+            let label = format!("label{i}");
+            assert_eq!(
+                i,
+                snapshot["labeled_counter"]["telemetry.labeled_metric"][&label]
+            );
+        }
+
+        drop(glean);
+    }
+
+    // Force a reload
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+
+        // Try to store another label
+        labeled.get("new_label").add_sync(&glean, 40);
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", false)
+            .unwrap();
+
+        // Check that the old data is still there
+        for i in 1..=16 {
+            let label = format!("label{i}");
+            assert_eq!(
+                i,
+                snapshot["labeled_counter"]["telemetry.labeled_metric"][&label]
+            );
+        }
+
+        // The new label lands in the __other__ bucket, due to too many labels
+        assert_eq!(
+            40,
+            snapshot["labeled_counter"]["telemetry.labeled_metric"]["__other__"]
+        );
+    }
+}
+
+#[test]
+fn caching_metrics_with_dynamic_labels() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "cached_labels".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    // Create multiple metric instances and cache them for later use.
+    let metrics = (1..=20)
+        .map(|i| {
+            let label = format!("label{i}");
+            labeled.get(label)
+        })
+        .collect::<Vec<_>>();
+
+    // Only now use them.
+    for metric in metrics {
+        metric.add_sync(&glean, 1);
+    }
+
+    // The maximum number of labels we store is 16.
+    // So we should have put 4 metrics in the __other__ bucket.
+    let other = labeled.get("__other__");
+    assert_eq!(Some(4), other.get_value(&glean, Some("store1")));
+}
+
+#[test]
+fn caching_metrics_with_dynamic_labels_across_pings() {
+    let (glean, _t) = new_glean(None);
+    let labeled = LabeledCounter::new(
+        CommonMetricData {
+            name: "cached_labels2".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        None,
+    );
+
+    // Create multiple metric instances and cache them for later use.
+    let metrics = (1..=20)
+        .map(|i| {
+            let label = format!("label{i}");
+            labeled.get(label)
+        })
+        .collect::<Vec<_>>();
+
+    // Only now use them.
+    for metric in &metrics {
+        metric.add_sync(&glean, 1);
+    }
+
+    // The maximum number of labels we store is 16.
+    // So we should have put 4 metrics in the __other__ bucket.
+    let other = labeled.get("__other__");
+    assert_eq!(Some(4), other.get_value(&glean, Some("store1")));
+
+    // Snapshot (so we can inspect the JSON)
+    // and clear out storage (the same way submitting a ping would)
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    // We didn't send the 20th label
+    assert_eq!(
+        json!(null),
+        snapshot["labeled_counter"]["telemetry.cached_labels2"]["label20"]
+    );
+
+    // We now set the ones that ended up in `__other__` before.
+    // Note: indexing is zero-based,
+    // but we later check the names, so let's offset it by 1.
+    metrics[16].add_sync(&glean, 17);
+    metrics[17].add_sync(&glean, 18);
+    metrics[18].add_sync(&glean, 19);
+    metrics[19].add_sync(&glean, 20);
+
+    assert_eq!(Some(17), metrics[16].get_value(&glean, Some("store1")));
+    assert_eq!(Some(18), metrics[17].get_value(&glean, Some("store1")));
+    assert_eq!(Some(19), metrics[18].get_value(&glean, Some("store1")));
+    assert_eq!(Some(20), metrics[19].get_value(&glean, Some("store1")));
+    assert_eq!(None, other.get_value(&glean, Some("store1")));
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.storage(), "store1", true)
+        .unwrap();
+
+    let cached_labels = &snapshot["labeled_counter"]["telemetry.cached_labels2"];
+    assert_eq!(json!(17), cached_labels["label17"]);
+    assert_eq!(json!(18), cached_labels["label18"]);
+    assert_eq!(json!(19), cached_labels["label19"]);
+    assert_eq!(json!(20), cached_labels["label20"]);
+    assert_eq!(json!(null), cached_labels["__other__"]);
+}
diff --git a/third_party/rust/glean-core/tests/memory_distribution.rs b/third_party/rust/glean-core/tests/memory_distribution.rs
new file mode 100644
index 0000000000..83ca84ddd5
--- /dev/null
+++ b/third_party/rust/glean-core/tests/memory_distribution.rs
@@ -0,0 +1,194 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+#[test]
+fn serializer_should_correctly_serialize_memory_distribution() {
+    let (mut tempdir, _) = tempdir();
+
+    let memory_unit = MemoryUnit::Kilobyte;
+    let kb = 1024;
+
+    {
+        let (glean, dir) = new_glean(Some(tempdir));
+        tempdir = dir;
+
+        let metric = MemoryDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            memory_unit,
+        );
+
+        metric.accumulate_sync(&glean, 100_000);
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        assert_eq!(snapshot.sum, 100_000 * kb);
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+
+        // We check the exact format to catch changes to the serialization.
+        let expected = json!({
+            "sum": 100_000 * kb,
+            "values": {
+                "99108124": 1,
+                "103496016": 0,
+            }
+        });
+        assert_eq!(
+            expected,
+            snapshot["memory_distribution"]["telemetry.distribution"]
+        );
+    }
+}
+
+#[test]
+fn set_value_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = MemoryDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names.clone(),
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        MemoryUnit::Byte,
+    );
+
+    metric.accumulate_sync(&glean, 100_000);
+
+    // We check the exact format to catch changes to the serialization.
+    let expected = json!({
+        "sum": 100_000,
+        "values": {
+            "96785": 1,
+            "101070": 0,
+        }
+    });
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            expected,
+            snapshot["memory_distribution"]["telemetry.distribution"]
+        );
+    }
+}
+
+// SKIPPED from glean-ac: memory distributions must not accumulate negative values
+// This test doesn't apply to Rust, because we're using unsigned integers.
+
+#[test]
+fn the_accumulate_samples_api_correctly_stores_memory_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = MemoryDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        MemoryUnit::Kilobyte,
+    );
+
+    // Accumulate the samples. We intentionally do not report
+    // negative values to not trigger error reporting.
+    metric.accumulate_samples_sync(&glean, [1, 2, 3].to_vec());
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    let kb = 1024;
+
+    // Check that we got the right sum of samples.
+    assert_eq!(snapshot.sum, 6 * kb);
+
+    // We should get a sample in 3 buckets.
+    // These numbers are a bit magic, but they correspond to
+    // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+    assert_eq!(1, snapshot.values[&1023]);
+    assert_eq!(1, snapshot.values[&2047]);
+    assert_eq!(1, snapshot.values[&3024]);
+
+    // No errors should be reported.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+}
+
+#[test]
+fn the_accumulate_samples_api_correctly_handles_negative_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = MemoryDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        MemoryUnit::Kilobyte,
+    );
+
+    // Accumulate the samples.
+    metric.accumulate_samples_sync(&glean, [-1, 1, 2, 3].to_vec());
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    let kb = 1024;
+
+    // Check that we got the right sum of samples.
+    assert_eq!(snapshot.sum, 6 * kb);
+
+    // We should get a sample in 3 buckets.
+    // These numbers are a bit magic, but they correspond to
+    // `hist.sample_to_bucket_minimum(i * kb)` for `i = 1..=3`.
+    assert_eq!(1, snapshot.values[&1023]);
+    assert_eq!(1, snapshot.values[&2047]);
+    assert_eq!(1, snapshot.values[&3024]);
+
+    // 1 error should be reported.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
diff --git a/third_party/rust/glean-core/tests/ping.rs b/third_party/rust/glean-core/tests/ping.rs
new file mode 100644
index 0000000000..915582acc0
--- /dev/null
+++ b/third_party/rust/glean-core/tests/ping.rs
@@ -0,0 +1,249 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use std::collections::HashMap;
+
+use glean_core::metrics::*;
+use glean_core::CommonMetricData;
+use glean_core::Lifetime;
+
+#[test]
+fn write_ping_to_disk() {
+    let (mut glean, _temp) = new_glean(None);
+
+    let ping = PingType::new("metrics", true, false, vec![]);
+    glean.register_ping_type(&ping);
+
+    // We need to store a metric as an empty ping is not stored.
+    let counter = CounterMetric::new(CommonMetricData {
+        name: "counter".into(),
+        category: "local".into(),
+        send_in_pings: vec!["metrics".into()],
+        ..Default::default()
+    });
+    counter.add_sync(&glean, 1);
+
+    assert!(ping.submit_sync(&glean, None));
+
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn disabling_upload_clears_pending_pings() {
+    let (mut glean, _t) = new_glean(None);
+
+    let ping = PingType::new("metrics", true, false, vec![]);
+    glean.register_ping_type(&ping);
+
+    // We need to store a metric as an empty ping is not stored.
+    let counter = CounterMetric::new(CommonMetricData {
+        name: "counter".into(),
+        category: "local".into(),
+        send_in_pings: vec!["metrics".into()],
+        ..Default::default()
+    });
+
+    counter.add_sync(&glean, 1);
+    assert!(ping.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+    // At this point no deletion_request ping should exist
+    // (that is: it's directory should not exist at all)
+    assert!(get_deletion_pings(glean.get_data_path()).is_err());
+
+    glean.set_upload_enabled(false);
+    assert_eq!(0, get_queued_pings(glean.get_data_path()).unwrap().len());
+    // Disabling upload generates a deletion ping
+    let dpings = get_deletion_pings(glean.get_data_path()).unwrap();
+    assert_eq!(1, dpings.len());
+    let payload = &dpings[0].1;
+    assert_eq!(
+        "set_upload_enabled",
+        payload["ping_info"].as_object().unwrap()["reason"]
+            .as_str()
+            .unwrap()
+    );
+
+    glean.set_upload_enabled(true);
+    assert_eq!(0, get_queued_pings(glean.get_data_path()).unwrap().len());
+
+    counter.add_sync(&glean, 1);
+    assert!(ping.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn deletion_request_only_when_toggled_from_on_to_off() {
+    let (mut glean, _t) = new_glean(None);
+
+    // Disabling upload generates a deletion ping
+    glean.set_upload_enabled(false);
+    let dpings = get_deletion_pings(glean.get_data_path()).unwrap();
+    assert_eq!(1, dpings.len());
+    let payload = &dpings[0].1;
+    assert_eq!(
+        "set_upload_enabled",
+        payload["ping_info"].as_object().unwrap()["reason"]
+            .as_str()
+            .unwrap()
+    );
+
+    // Re-setting it to `false` should not generate an additional ping.
+    // As we didn't clear the pending ping, that's the only one that sticks around.
+    glean.set_upload_enabled(false);
+    assert_eq!(1, get_deletion_pings(glean.get_data_path()).unwrap().len());
+
+    // Toggling back to true won't generate a ping either.
+    glean.set_upload_enabled(true);
+    assert_eq!(1, get_deletion_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn empty_pings_with_flag_are_sent() {
+    let (mut glean, _t) = new_glean(None);
+
+    let ping1 = PingType::new("custom-ping1", true, true, vec![]);
+    glean.register_ping_type(&ping1);
+    let ping2 = PingType::new("custom-ping2", true, false, vec![]);
+    glean.register_ping_type(&ping2);
+
+    // No data is stored in either of the custom pings
+
+    // Sending this should succeed.
+    assert!(ping1.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+
+    // Sending this should fail.
+    assert!(!ping2.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn test_pings_submitted_metric() {
+    let (mut glean, _temp) = new_glean(None);
+
+    // Reconstructed here so we can test it without reaching into the library
+    // internals.
+    let pings_submitted = LabeledCounter::new(
+        CommonMetricData {
+            name: "pings_submitted".into(),
+            category: "glean.validation".into(),
+            send_in_pings: vec!["metrics".into(), "baseline".into()],
+            lifetime: Lifetime::Ping,
+            disabled: false,
+            dynamic_label: None,
+        },
+        None,
+    );
+
+    let metrics_ping = PingType::new("metrics", true, false, vec![]);
+    glean.register_ping_type(&metrics_ping);
+
+    let baseline_ping = PingType::new("baseline", true, false, vec![]);
+    glean.register_ping_type(&baseline_ping);
+
+    // We need to store a metric as an empty ping is not stored.
+    let counter = CounterMetric::new(CommonMetricData {
+        name: "counter".into(),
+        category: "local".into(),
+        send_in_pings: vec!["metrics".into()],
+        ..Default::default()
+    });
+    counter.add_sync(&glean, 1);
+
+    assert!(metrics_ping.submit_sync(&glean, None));
+
+    // Check recording in the metrics ping
+    assert_eq!(
+        Some(1),
+        pings_submitted.get("metrics").get_value(&glean, "metrics")
+    );
+    assert_eq!(
+        None,
+        pings_submitted.get("baseline").get_value(&glean, "metrics")
+    );
+
+    // Check recording in the baseline ping
+    assert_eq!(
+        Some(1),
+        pings_submitted.get("metrics").get_value(&glean, "baseline")
+    );
+    assert_eq!(
+        None,
+        pings_submitted
+            .get("baseline")
+            .get_value(&glean, "baseline")
+    );
+
+    // Trigger 2 baseline pings.
+    // This should record a count of 2 baseline pings in the metrics ping, but
+    // it resets each time on the baseline ping, so we should only ever get 1
+    // baseline ping recorded in the baseline ping itsef.
+    assert!(baseline_ping.submit_sync(&glean, None));
+    assert!(baseline_ping.submit_sync(&glean, None));
+
+    // Check recording in the metrics ping
+    assert_eq!(
+        Some(1),
+        pings_submitted
+            .get("metrics")
+            .get_value(&glean, Some("metrics"))
+    );
+    assert_eq!(
+        Some(2),
+        pings_submitted
+            .get("baseline")
+            .get_value(&glean, Some("metrics"))
+    );
+
+    // Check recording in the baseline ping
+    assert_eq!(
+        None,
+        pings_submitted
+            .get("metrics")
+            .get_value(&glean, Some("baseline"))
+    );
+    assert_eq!(
+        Some(1),
+        pings_submitted
+            .get("baseline")
+            .get_value(&glean, Some("baseline"))
+    );
+}
+
+#[test]
+fn events_ping_with_metric_but_no_events_is_not_sent() {
+    let (mut glean, _t) = new_glean(None);
+
+    let events_ping = PingType::new("events", true, true, vec![]);
+    glean.register_ping_type(&events_ping);
+    let counter = CounterMetric::new(CommonMetricData {
+        name: "counter".into(),
+        category: "local".into(),
+        send_in_pings: vec!["events".into()],
+        ..Default::default()
+    });
+    counter.add_sync(&glean, 1);
+
+    // Sending this should fail.
+    assert!(!events_ping.submit_sync(&glean, None));
+    assert!(get_queued_pings(glean.get_data_path()).is_err());
+
+    let event = EventMetric::new(
+        CommonMetricData {
+            name: "name".into(),
+            category: "category".into(),
+            send_in_pings: vec!["events".into()],
+            ..Default::default()
+        },
+        vec![],
+    );
+    event.record_sync(&glean, 0, HashMap::new());
+
+    // Sending this should now succeed.
+    assert!(events_ping.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
diff --git a/third_party/rust/glean-core/tests/ping_maker.rs b/third_party/rust/glean-core/tests/ping_maker.rs
new file mode 100644
index 0000000000..e88b23916b
--- /dev/null
+++ b/third_party/rust/glean-core/tests/ping_maker.rs
@@ -0,0 +1,220 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use glean_core::metrics::*;
+use glean_core::ping::PingMaker;
+use glean_core::{CommonMetricData, Glean, Lifetime};
+
+fn set_up_basic_ping() -> (Glean, PingMaker, PingType, tempfile::TempDir) {
+    let (tempdir, _) = tempdir();
+    let (mut glean, t) = new_glean(Some(tempdir));
+    let ping_maker = PingMaker::new();
+    let ping_type = PingType::new("store1", true, false, vec![]);
+    glean.register_ping_type(&ping_type);
+
+    // Record something, so the ping will have data
+    let metric = BooleanMetric::new(CommonMetricData {
+        name: "boolean_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::User,
+        ..Default::default()
+    });
+    metric.set_sync(&glean, true);
+
+    (glean, ping_maker, ping_type, t)
+}
+
+#[test]
+fn ping_info_must_contain_a_nonempty_start_and_end_time() {
+    let (glean, ping_maker, ping_type, _t) = set_up_basic_ping();
+
+    let ping = ping_maker
+        .collect(&glean, &ping_type, None, "", "")
+        .unwrap();
+    let ping_info = ping.content["ping_info"].as_object().unwrap();
+
+    let start_time_str = ping_info["start_time"].as_str().unwrap();
+    let start_time_date = iso8601_to_chrono(&iso8601::datetime(start_time_str).unwrap());
+
+    let end_time_str = ping_info["end_time"].as_str().unwrap();
+    let end_time_date = iso8601_to_chrono(&iso8601::datetime(end_time_str).unwrap());
+
+    assert!(start_time_date <= end_time_date);
+}
+
+#[test]
+fn get_ping_info_must_report_all_the_required_fields() {
+    let (glean, ping_maker, ping_type, _t) = set_up_basic_ping();
+
+    let ping = ping_maker
+        .collect(&glean, &ping_type, None, "", "")
+        .unwrap();
+    let ping_info = ping.content["ping_info"].as_object().unwrap();
+
+    assert!(ping_info.get("start_time").is_some());
+    assert!(ping_info.get("end_time").is_some());
+    assert!(ping_info.get("seq").is_some());
+}
+
+#[test]
+fn get_client_info_must_report_all_the_available_data() {
+    let (glean, ping_maker, ping_type, _t) = set_up_basic_ping();
+
+    let ping = ping_maker
+        .collect(&glean, &ping_type, None, "", "")
+        .unwrap();
+    let client_info = ping.content["client_info"].as_object().unwrap();
+
+    client_info["telemetry_sdk_build"].as_str().unwrap();
+}
+
+#[test]
+fn collect_must_report_none_when_no_data_is_stored() {
+    // NOTE: This is a behavior change from glean-ac which returned an empty
+    // string in this case. As this is an implementation detail and not part of
+    // the public API, it's safe to change this.
+
+    let (mut glean, ping_maker, ping_type, _t) = set_up_basic_ping();
+
+    let unknown_ping_type = PingType::new("unknown", true, false, vec![]);
+    glean.register_ping_type(&ping_type);
+
+    assert!(ping_maker
+        .collect(&glean, &unknown_ping_type, None, "", "")
+        .is_none());
+}
+
+#[test]
+fn seq_number_must_be_sequential() {
+    let (glean, ping_maker, _ping_type, _t) = set_up_basic_ping();
+
+    let metric = BooleanMetric::new(CommonMetricData {
+        name: "boolean_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store2".into()],
+        disabled: false,
+        lifetime: Lifetime::User,
+        ..Default::default()
+    });
+    metric.set_sync(&glean, true);
+
+    for i in 0..=1 {
+        for ping_name in ["store1", "store2"].iter() {
+            let ping_type = PingType::new(*ping_name, true, false, vec![]);
+            let ping = ping_maker
+                .collect(&glean, &ping_type, None, "", "")
+                .unwrap();
+            let seq_num = ping.content["ping_info"]["seq"].as_i64().unwrap();
+            // Ensure sequence numbers in different stores are independent of
+            // each other
+            assert_eq!(i, seq_num);
+        }
+    }
+
+    // Test that ping sequence numbers increase independently.
+    {
+        let ping_type = PingType::new("store1", true, false, vec![]);
+
+        // 3rd ping of store1
+        let ping = ping_maker
+            .collect(&glean, &ping_type, None, "", "")
+            .unwrap();
+        let seq_num = ping.content["ping_info"]["seq"].as_i64().unwrap();
+        assert_eq!(2, seq_num);
+
+        // 4th ping of store1
+        let ping = ping_maker
+            .collect(&glean, &ping_type, None, "", "")
+            .unwrap();
+        let seq_num = ping.content["ping_info"]["seq"].as_i64().unwrap();
+        assert_eq!(3, seq_num);
+    }
+
+    {
+        let ping_type = PingType::new("store2", true, false, vec![]);
+
+        // 3rd ping of store2
+        let ping = ping_maker
+            .collect(&glean, &ping_type, None, "", "")
+            .unwrap();
+        let seq_num = ping.content["ping_info"]["seq"].as_i64().unwrap();
+        assert_eq!(2, seq_num);
+    }
+
+    {
+        let ping_type = PingType::new("store1", true, false, vec![]);
+
+        // 5th ping of store1
+        let ping = ping_maker
+            .collect(&glean, &ping_type, None, "", "")
+            .unwrap();
+        let seq_num = ping.content["ping_info"]["seq"].as_i64().unwrap();
+        assert_eq!(4, seq_num);
+    }
+}
+
+#[test]
+fn clear_pending_pings() {
+    let (mut glean, _t) = new_glean(None);
+    let ping_maker = PingMaker::new();
+    let ping_type = PingType::new("store1", true, false, vec![]);
+    glean.register_ping_type(&ping_type);
+
+    // Record something, so the ping will have data
+    let metric = BooleanMetric::new(CommonMetricData {
+        name: "boolean_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::User,
+        ..Default::default()
+    });
+    metric.set_sync(&glean, true);
+
+    assert!(ping_type.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+
+    assert!(ping_maker
+        .clear_pending_pings(glean.get_data_path())
+        .is_ok());
+    assert_eq!(0, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn no_pings_submitted_if_upload_disabled() {
+    // Regression test, bug 1603571
+
+    let (mut glean, _t) = new_glean(None);
+    let ping_type = PingType::new("store1", true, true, vec![]);
+    glean.register_ping_type(&ping_type);
+
+    assert!(ping_type.submit_sync(&glean, None));
+    assert_eq!(1, get_queued_pings(glean.get_data_path()).unwrap().len());
+
+    // Disable upload, then try to sumbit
+    glean.set_upload_enabled(false);
+
+    // Test again through the direct call
+    assert!(!ping_type.submit_sync(&glean, None));
+    assert_eq!(0, get_queued_pings(glean.get_data_path()).unwrap().len());
+}
+
+#[test]
+fn metadata_is_correctly_added_when_necessary() {
+    let (mut glean, _t) = new_glean(None);
+    glean.set_debug_view_tag("valid-tag");
+    let ping_type = PingType::new("store1", true, true, vec![]);
+    glean.register_ping_type(&ping_type);
+
+    assert!(ping_type.submit_sync(&glean, None));
+
+    let (_, _, metadata) = &get_queued_pings(glean.get_data_path()).unwrap()[0];
+    let headers = metadata.as_ref().unwrap().get("headers").unwrap();
+    assert_eq!(headers.get("X-Debug-ID").unwrap(), "valid-tag");
+}
diff --git a/third_party/rust/glean-core/tests/quantity.rs b/third_party/rust/glean-core/tests/quantity.rs
new file mode 100644
index 0000000000..b16c5fd992
--- /dev/null
+++ b/third_party/rust/glean-core/tests/quantity.rs
@@ -0,0 +1,118 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+// SKIPPED from glean-ac: quantity deserializer should correctly parse integers
+// This test doesn't really apply to rkv
+
+#[test]
+fn quantity_serializer_should_correctly_serialize_quantities() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = QuantityMetric::new(CommonMetricData {
+            name: "quantity_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.set_sync(&glean, 1);
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"quantity": {"telemetry.quantity_metric": 1}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"quantity": {"telemetry.quantity_metric": 1}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_value_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = QuantityMetric::new(CommonMetricData {
+        name: "quantity_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, 1);
+
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"quantity": {"telemetry.quantity_metric": 1}}),
+            snapshot
+        );
+    }
+}
+
+// SKIPPED from glean-ac: quantities are serialized in the correct JSON format
+// Completely redundant with other tests.
+
+#[test]
+fn quantities_must_not_set_when_passed_negative() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = QuantityMetric::new(CommonMetricData {
+        name: "quantity_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Application,
+        ..Default::default()
+    });
+
+    // Attempt to set the quantity with negative
+    metric.set_sync(&glean, -1);
+    // Check that nothing was recorded
+    assert!(metric.get_value(&glean, "store1").is_none());
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
diff --git a/third_party/rust/glean-core/tests/rate.rs b/third_party/rust/glean-core/tests/rate.rs
new file mode 100644
index 0000000000..f81e10cb53
--- /dev/null
+++ b/third_party/rust/glean-core/tests/rate.rs
@@ -0,0 +1,134 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use glean_core::metrics::*;
+use glean_core::CommonMetricData;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+
+#[test]
+fn rate_smoke() {
+    let (glean, _t) = new_glean(None);
+
+    let metric: RateMetric = RateMetric::new(CommonMetricData {
+        name: "rate".into(),
+        category: "test".into(),
+        send_in_pings: vec!["test1".into()],
+        ..Default::default()
+    });
+
+    // Adding 0 doesn't error.
+    metric.add_to_numerator_sync(&glean, 0);
+    metric.add_to_denominator_sync(&glean, 0);
+
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+
+    // Adding a negative value errors.
+    metric.add_to_numerator_sync(&glean, -1);
+    metric.add_to_denominator_sync(&glean, -1);
+
+    assert_eq!(
+        Ok(2),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue),
+    );
+
+    // Getting the value returns 0s if that's all we have.
+    assert_eq!(metric.get_value(&glean, None), Some((0, 0).into()));
+
+    // And normal values of course work.
+    metric.add_to_numerator_sync(&glean, 22);
+    metric.add_to_denominator_sync(&glean, 7);
+
+    assert_eq!(metric.get_value(&glean, None), Some((22, 7).into()));
+}
+
+#[test]
+fn numerator_smoke() {
+    let (glean, _t) = new_glean(None);
+
+    let metric: NumeratorMetric = NumeratorMetric::new(CommonMetricData {
+        name: "rate".into(),
+        category: "test".into(),
+        send_in_pings: vec!["test1".into()],
+        ..Default::default()
+    });
+
+    // Adding 0 doesn't error.
+    metric.add_to_numerator_sync(&glean, 0);
+
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+
+    // Adding a negative value errors.
+    metric.add_to_numerator_sync(&glean, -1);
+
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue),
+    );
+
+    // Getting the value returns 0s if that's all we have.
+    let data = metric.get_value(&glean, None).unwrap();
+    assert_eq!(0, data.numerator);
+    assert_eq!(0, data.denominator);
+
+    // And normal values of course work.
+    metric.add_to_numerator_sync(&glean, 22);
+
+    let data = metric.get_value(&glean, None).unwrap();
+    assert_eq!(22, data.numerator);
+    assert_eq!(0, data.denominator);
+}
+
+#[test]
+fn denominator_smoke() {
+    let (glean, _t) = new_glean(None);
+
+    let meta1 = CommonMetricData {
+        name: "rate1".into(),
+        category: "test".into(),
+        send_in_pings: vec!["test1".into()],
+        ..Default::default()
+    };
+
+    let meta2 = CommonMetricData {
+        name: "rate2".into(),
+        category: "test".into(),
+        send_in_pings: vec!["test1".into()],
+        ..Default::default()
+    };
+
+    // This acts like a normal counter.
+    let denom: DenominatorMetric = DenominatorMetric::new(
+        CommonMetricData {
+            name: "counter".into(),
+            category: "test".into(),
+            send_in_pings: vec!["test1".into()],
+            ..Default::default()
+        },
+        vec![meta1.clone(), meta2.clone()],
+    );
+
+    let num1 = NumeratorMetric::new(meta1);
+    let num2 = NumeratorMetric::new(meta2);
+
+    num1.add_to_numerator_sync(&glean, 3);
+    num2.add_to_numerator_sync(&glean, 5);
+
+    denom.add_sync(&glean, 7);
+
+    // no errors.
+    assert!(test_get_num_recorded_errors(&glean, num1.meta(), ErrorType::InvalidValue).is_err());
+    assert!(test_get_num_recorded_errors(&glean, num2.meta(), ErrorType::InvalidValue).is_err());
+
+    // Getting the value returns 0s if that's all we have.
+    let data = num1.get_value(&glean, None).unwrap();
+    assert_eq!(3, data.numerator);
+    assert_eq!(7, data.denominator);
+
+    let data = num2.get_value(&glean, None).unwrap();
+    assert_eq!(5, data.numerator);
+    assert_eq!(7, data.denominator);
+}
diff --git a/third_party/rust/glean-core/tests/storage.rs b/third_party/rust/glean-core/tests/storage.rs
new file mode 100644
index 0000000000..238fe6855c
--- /dev/null
+++ b/third_party/rust/glean-core/tests/storage.rs
@@ -0,0 +1,105 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{CommonMetricData, Lifetime};
+
+#[test]
+fn snapshot_returns_none_if_nothing_is_recorded_in_the_store() {
+    let (glean, _t) = new_glean(None);
+    assert!(StorageManager
+        .snapshot(glean.storage(), "unknown_store", true)
+        .is_none())
+}
+
+#[test]
+fn can_snapshot() {
+    let (glean, _t) = new_glean(None);
+
+    let local_metric = StringMetric::new(CommonMetricData {
+        name: "can_snapshot_local_metric".into(),
+        category: "local".into(),
+        send_in_pings: vec!["store".into()],
+        ..Default::default()
+    });
+
+    local_metric.set_sync(&glean, "snapshot 42");
+
+    assert!(StorageManager
+        .snapshot(glean.storage(), "store", true)
+        .is_some())
+}
+
+#[test]
+fn snapshot_correctly_clears_the_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = CounterMetric::new(CommonMetricData {
+        name: "metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names,
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.add_sync(&glean, 1);
+
+    // Get the snapshot from "store1" and clear it.
+    let snapshot = StorageManager.snapshot(glean.storage(), "store1", true);
+    assert!(snapshot.is_some());
+    // Check that getting a new snapshot for "store1" returns an empty store.
+    assert!(StorageManager
+        .snapshot(glean.storage(), "store1", false)
+        .is_none());
+    // Check that we get the right data from both the stores. Clearing "store1" must
+    // not clear "store2" as well.
+    let snapshot2 = StorageManager.snapshot(glean.storage(), "store2", true);
+    assert!(snapshot2.is_some());
+}
+
+#[test]
+fn storage_is_thread_safe() {
+    use std::sync::{Arc, Barrier, Mutex};
+    use std::thread;
+
+    let (glean, _t) = new_glean(None);
+    let glean = Arc::new(Mutex::new(glean));
+
+    let threadsafe_metric = CounterMetric::new(CommonMetricData {
+        name: "threadsafe".into(),
+        category: "global".into(),
+        send_in_pings: vec!["core".into(), "metrics".into()],
+        ..Default::default()
+    });
+    let threadsafe_metric = Arc::new(threadsafe_metric);
+
+    let barrier = Arc::new(Barrier::new(2));
+    let c = barrier.clone();
+    let threadsafe_metric_clone = threadsafe_metric.clone();
+    let glean_clone = glean.clone();
+    let child = thread::spawn(move || {
+        threadsafe_metric_clone.add_sync(&glean_clone.lock().unwrap(), 1);
+        c.wait();
+        threadsafe_metric_clone.add_sync(&glean_clone.lock().unwrap(), 1);
+    });
+
+    threadsafe_metric.add_sync(&glean.lock().unwrap(), 1);
+    barrier.wait();
+    threadsafe_metric.add_sync(&glean.lock().unwrap(), 1);
+
+    child.join().unwrap();
+
+    let snapshot = StorageManager
+        .snapshot_as_json(glean.lock().unwrap().storage(), "core", true)
+        .unwrap();
+    assert_eq!(json!({"counter": { "global.threadsafe": 4 }}), snapshot);
+}
diff --git a/third_party/rust/glean-core/tests/string.rs b/third_party/rust/glean-core/tests/string.rs
new file mode 100644
index 0000000000..3ccfa8f494
--- /dev/null
+++ b/third_party/rust/glean-core/tests/string.rs
@@ -0,0 +1,121 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// SKIPPED from glean-ac: string deserializer should correctly parse integers
+// This test doesn't really apply to rkv
+
+#[test]
+fn string_serializer_should_correctly_serialize_strings() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = StringMetric::new(CommonMetricData {
+            name: "string_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.set_sync(&glean, "test_string_value");
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"string": {"telemetry.string_metric": "test_string_value"}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"string": {"telemetry.string_metric": "test_string_value"}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = StringMetric::new(CommonMetricData {
+        name: "string_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, "test_string_value");
+
+    // Check that the data was correctly set in each store.
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"string": {"telemetry.string_metric": "test_string_value"}}),
+            snapshot
+        );
+    }
+}
+
+// SKIPPED from glean-ac: strings are serialized in the correct JSON format
+// Completely redundant with other tests.
+
+#[test]
+fn long_string_values_are_truncated() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = StringMetric::new(CommonMetricData {
+        name: "string_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    let test_sting = "01234567890".repeat(20);
+    metric.set_sync(&glean, test_sting.clone());
+
+    // Check that data was truncated
+    assert_eq!(
+        test_sting[..100],
+        metric.get_value(&glean, "store1").unwrap()
+    );
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
diff --git a/third_party/rust/glean-core/tests/string_list.rs b/third_party/rust/glean-core/tests/string_list.rs
new file mode 100644
index 0000000000..8e1589e8a9
--- /dev/null
+++ b/third_party/rust/glean-core/tests/string_list.rs
@@ -0,0 +1,245 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, CommonMetricData, ErrorType, Lifetime};
+
+#[test]
+fn list_can_store_multiple_items() {
+    let (glean, _t) = new_glean(None);
+
+    let list: StringListMetric = StringListMetric::new(CommonMetricData {
+        name: "list".into(),
+        category: "local".into(),
+        send_in_pings: vec!["core".into()],
+        ..Default::default()
+    });
+
+    list.add_sync(&glean, "first");
+    assert_eq!(list.get_value(&glean, "core").unwrap(), vec!["first"]);
+
+    list.add_sync(&glean, "second");
+    assert_eq!(
+        list.get_value(&glean, "core").unwrap(),
+        vec!["first", "second"]
+    );
+
+    list.set_sync(&glean, vec!["third".into()]);
+    assert_eq!(list.get_value(&glean, "core").unwrap(), vec!["third"]);
+
+    list.add_sync(&glean, "fourth");
+    assert_eq!(
+        list.get_value(&glean, "core").unwrap(),
+        vec!["third", "fourth"]
+    );
+}
+
+#[test]
+fn stringlist_serializer_should_correctly_serialize_stringlists() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = StringListMetric::new(CommonMetricData {
+            name: "string_list_metric".into(),
+            category: "telemetry.test".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+        metric.set_sync(&glean, vec!["test_string_1".into(), "test_string_2".into()]);
+    }
+
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"string_list": {"telemetry.test.string_list_metric": ["test_string_1", "test_string_2"]}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = StringListMetric::new(CommonMetricData {
+        name: "string_list_metric".into(),
+        category: "telemetry.test".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, vec!["test_string_1".into(), "test_string_2".into()]);
+
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"string_list": {"telemetry.test.string_list_metric": ["test_string_1", "test_string_2"]}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn long_string_values_are_truncated() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = StringListMetric::new(CommonMetricData {
+        name: "string_list_metric".into(),
+        category: "telemetry.test".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    let test_string = "0123456789".repeat(20);
+    metric.add_sync(&glean, test_string.clone());
+
+    // Ensure the string was truncated to the proper length.
+    assert_eq!(
+        vec![test_string[..50].to_string()],
+        metric.get_value(&glean, "store1").unwrap()
+    );
+
+    // Ensure the error has been recorded.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+
+    metric.set_sync(&glean, vec![test_string.clone()]);
+
+    // Ensure the string was truncated to the proper length.
+    assert_eq!(
+        vec![test_string[..50].to_string()],
+        metric.get_value(&glean, "store1").unwrap()
+    );
+
+    // Ensure the error has been recorded.
+    assert_eq!(
+        Ok(2),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
+
+#[test]
+fn disabled_string_lists_dont_record() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = StringListMetric::new(CommonMetricData {
+        name: "string_list_metric".into(),
+        category: "telemetry.test".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: true,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.add_sync(&glean, "test_string".repeat(20));
+
+    // Ensure the string was not added.
+    assert_eq!(None, metric.get_value(&glean, "store1"));
+
+    metric.set_sync(&glean, vec!["test_string_2".repeat(20)]);
+
+    // Ensure the stringlist was not set.
+    assert_eq!(None, metric.get_value(&glean, "store1"));
+
+    // Ensure no error was recorded.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+}
+
+#[test]
+fn string_lists_dont_exceed_max_items() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = StringListMetric::new(CommonMetricData {
+        name: "string_list_metric".into(),
+        category: "telemetry.test".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    for _n in 1..21 {
+        metric.add_sync(&glean, "test_string");
+    }
+
+    let expected: Vec<String> = "test_string "
+        .repeat(20)
+        .split_whitespace()
+        .map(|s| s.to_string())
+        .collect();
+    assert_eq!(expected, metric.get_value(&glean, "store1").unwrap());
+
+    // Ensure the 21st string wasn't added.
+    metric.add_sync(&glean, "test_string");
+    assert_eq!(expected, metric.get_value(&glean, "store1").unwrap());
+
+    // Ensure we recorded the error.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+
+    // Try to set it to a list that's too long. Ensure it cuts off at 20 elements.
+    let too_many: Vec<String> = "test_string "
+        .repeat(21)
+        .split_whitespace()
+        .map(|s| s.to_string())
+        .collect();
+    metric.set_sync(&glean, too_many);
+    assert_eq!(expected, metric.get_value(&glean, "store1").unwrap());
+
+    assert_eq!(
+        Ok(2),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
+
+#[test]
+fn set_does_not_record_error_when_receiving_empty_list() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = StringListMetric::new(CommonMetricData {
+        name: "string_list_metric".into(),
+        category: "telemetry.test".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, vec![]);
+
+    // Ensure the empty list was added
+    assert_eq!(Some(vec![]), metric.get_value(&glean, "store1"));
+
+    // Ensure we didn't record an error.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+}
diff --git a/third_party/rust/glean-core/tests/text.rs b/third_party/rust/glean-core/tests/text.rs
new file mode 100644
index 0000000000..2592e45899
--- /dev/null
+++ b/third_party/rust/glean-core/tests/text.rs
@@ -0,0 +1,115 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+#[test]
+fn text_serializer_should_correctly_serialize_strings() {
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = TextMetric::new(CommonMetricData {
+            name: "text_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.set_sync(&glean, "test_text_value");
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"text": {"telemetry.text_metric": "test_text_value"}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"text": {"telemetry.text_metric": "test_text_value"}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let metric = TextMetric::new(CommonMetricData {
+        name: "text_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_sync(&glean, "test_text_value");
+
+    // Check that the data was correctly set in each store.
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"text": {"telemetry.text_metric": "test_text_value"}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn long_text_values_are_truncated() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TextMetric::new(CommonMetricData {
+        name: "text_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: vec!["store1".into()],
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    let test_sting = "01234567890".repeat(200 * 1024);
+    metric.set_sync(&glean, test_sting.clone());
+
+    // Check that data was truncated
+    assert_eq!(
+        test_sting[..(200 * 1024)],
+        metric.get_value(&glean, "store1").unwrap()
+    );
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
diff --git a/third_party/rust/glean-core/tests/timespan.rs b/third_party/rust/glean-core/tests/timespan.rs
new file mode 100644
index 0000000000..c964c450d4
--- /dev/null
+++ b/third_party/rust/glean-core/tests/timespan.rs
@@ -0,0 +1,351 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+use std::time::Duration;
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+#[test]
+fn serializer_should_correctly_serialize_timespans() {
+    let (mut tempdir, _) = tempdir();
+
+    let duration = 60;
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = TimespanMetric::new(
+            CommonMetricData {
+                name: "timespan_metric".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            TimeUnit::Nanosecond,
+        );
+
+        metric.set_start(&glean, 0);
+        metric.set_stop(&glean, duration);
+
+        let val = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+        assert_eq!(duration, val, "Recorded timespan should be positive.");
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"timespan": {"telemetry.timespan_metric": { "value": duration, "time_unit": "nanosecond" }}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn single_elapsed_time_must_be_recorded() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let duration = 60;
+
+    metric.set_start(&glean, 0);
+    metric.set_stop(&glean, duration);
+
+    let val = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+    assert_eq!(duration, val, "Recorded timespan should be positive.");
+}
+
+// SKIPPED from glean-ac: multiple elapsed times must be correctly accumulated.
+// replaced by below after API change.
+
+#[test]
+fn second_timer_run_is_skipped() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let duration = 60;
+    metric.set_start(&glean, 0);
+    metric.set_stop(&glean, duration);
+
+    // No error should be recorded here: we had no prior value stored.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState).is_err());
+
+    let first_value = metric.get_value(&glean, "store1").unwrap();
+    assert_eq!(duration, first_value);
+
+    metric.set_start(&glean, 0);
+    metric.set_stop(&glean, duration * 2);
+
+    let second_value = metric.get_value(&glean, "store1").unwrap();
+    assert_eq!(second_value, first_value);
+
+    // Make sure that the error has been recorded: we had a stored value, the
+    // new measurement was dropped.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState)
+    );
+}
+
+#[test]
+fn recorded_time_conforms_to_resolution() {
+    let (glean, _t) = new_glean(None);
+
+    let ns_metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_ns".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let minute_metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_m".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Minute,
+    );
+
+    let duration = 60;
+    ns_metric.set_start(&glean, 0);
+    ns_metric.set_stop(&glean, duration);
+
+    let ns_value = ns_metric.get_value(&glean, "store1").unwrap();
+    assert_eq!(duration, ns_value);
+
+    // 1 minute in nanoseconds
+    let duration_minute = 60 * 1_000_000_000;
+    minute_metric.set_start(&glean, 0);
+    minute_metric.set_stop(&glean, duration_minute);
+
+    let minute_value = minute_metric.get_value(&glean, "store1").unwrap();
+    assert_eq!(1, minute_value);
+}
+
+// SKIPPED from glean-ac: accumulated short-lived timespans should not be discarded
+
+#[test]
+fn cancel_does_not_store() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    metric.set_start(&glean, 0);
+    metric.cancel();
+
+    assert_eq!(None, metric.get_value(&glean, "store1"));
+}
+
+#[test]
+fn nothing_stored_before_stop() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let duration = 60;
+
+    metric.set_start(&glean, 0);
+
+    assert_eq!(None, metric.get_value(&glean, "store1"));
+
+    metric.set_stop(&glean, duration);
+    assert_eq!(duration, metric.get_value(&glean, "store1").unwrap());
+}
+
+#[test]
+fn set_raw_time() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let time = Duration::from_secs(1);
+    metric.set_raw_sync(&glean, time);
+
+    let time_in_ns = time.as_nanos() as u64;
+    assert_eq!(Some(time_in_ns), metric.get_value(&glean, "store1"));
+}
+
+#[test]
+fn set_raw_time_does_nothing_when_timer_running() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let time = Duration::from_secs(42);
+
+    metric.set_start(&glean, 0);
+    metric.set_raw_sync(&glean, time);
+    metric.set_stop(&glean, 60);
+
+    // We expect the start/stop value, not the raw value.
+    assert_eq!(Some(60), metric.get_value(&glean, "store1"));
+
+    // Make sure that the error has been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState)
+    );
+}
+
+#[test]
+fn timespan_is_not_tracked_across_upload_toggle() {
+    let (mut glean, _t) = new_glean(None);
+
+    let metric = TimespanMetric::new(
+        CommonMetricData {
+            name: "timespan_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    // Timer is started.
+    metric.set_start(&glean, 0);
+    // User disables telemetry upload.
+    glean.set_upload_enabled(false);
+    // App code eventually stops the timer.
+    // We should clear internal state as upload is disabled.
+    metric.set_stop(&glean, 40);
+
+    // App code eventually starts the timer again.
+    // Upload is disabled, so this should not have any effect.
+    metric.set_start(&glean, 100);
+    // User enables telemetry upload again.
+    glean.set_upload_enabled(true);
+    // App code eventually stops the timer.
+    // None should be running.
+    metric.set_stop(&glean, 200);
+
+    // Nothing should have been recorded.
+    assert_eq!(None, metric.get_value(&glean, "store1"));
+
+    // Make sure that the error has been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState)
+    );
+}
+
+#[test]
+fn time_cannot_go_backwards() {
+    let (glean, _t) = new_glean(None);
+
+    let metric: TimespanMetric = TimespanMetric::new(
+        CommonMetricData {
+            name: "raw_timespan".into(),
+            category: "test".into(),
+            send_in_pings: vec!["test1".into()],
+            ..Default::default()
+        },
+        TimeUnit::Millisecond,
+    );
+
+    // Time cannot go backwards.
+    metric.set_start(&glean, 10);
+    metric.set_stop(&glean, 0);
+    assert!(metric.get_value(&glean, "test1").is_none());
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue),
+    );
+}
diff --git a/third_party/rust/glean-core/tests/timing_distribution.rs b/third_party/rust/glean-core/tests/timing_distribution.rs
new file mode 100644
index 0000000000..96f7fae5af
--- /dev/null
+++ b/third_party/rust/glean-core/tests/timing_distribution.rs
@@ -0,0 +1,431 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use std::time::Duration;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{test_get_num_recorded_errors, ErrorType};
+use glean_core::{CommonMetricData, Lifetime};
+
+// Tests ported from glean-ac
+
+#[test]
+fn serializer_should_correctly_serialize_timing_distribution() {
+    let (mut tempdir, _) = tempdir();
+
+    let duration = 60;
+    let time_unit = TimeUnit::Nanosecond;
+
+    {
+        let (glean, dir) = new_glean(Some(tempdir));
+        tempdir = dir;
+
+        let metric = TimingDistributionMetric::new(
+            CommonMetricData {
+                name: "distribution".into(),
+                category: "telemetry".into(),
+                send_in_pings: vec!["store1".into()],
+                disabled: false,
+                lifetime: Lifetime::Ping,
+                ..Default::default()
+            },
+            time_unit,
+        );
+
+        let id = 4u64.into();
+        metric.set_start(id, 0);
+        metric.set_stop_and_accumulate(&glean, id, duration);
+
+        let snapshot = metric
+            .get_value(&glean, "store1")
+            .expect("Value should be stored");
+
+        assert_eq!(snapshot.count, 1);
+        assert_eq!(snapshot.sum, duration as i64);
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+
+        // We check the exact format to catch changes to the serialization.
+        let expected = json!({
+            "sum": duration,
+            "values": {
+                "58": 1,
+                "64": 0,
+            }
+        });
+        assert_eq!(
+            expected,
+            snapshot["timing_distribution"]["telemetry.distribution"]
+        );
+    }
+}
+
+#[test]
+fn set_value_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+
+    let duration = 1;
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: store_names.clone(),
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let id = 4u64.into();
+    metric.set_start(id, 0);
+    metric.set_stop_and_accumulate(&glean, id, duration);
+
+    // We check the exact format to catch changes to the serialization.
+    let expected = json!({
+        "sum": 1,
+        "values": {
+            "1": 1,
+            "2": 0,
+        }
+    });
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            expected,
+            snapshot["timing_distribution"]["telemetry.distribution"]
+        );
+    }
+}
+
+#[test]
+fn timing_distributions_must_not_accumulate_negative_values() {
+    let (glean, _t) = new_glean(None);
+
+    let duration = 60;
+    let time_unit = TimeUnit::Nanosecond;
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        time_unit,
+    );
+
+    // Flip around the timestamps, this should result in a negative value which should be
+    // discarded.
+    let id = 4u64.into();
+    metric.set_start(id, duration);
+    metric.set_stop_and_accumulate(&glean, id, 0);
+
+    assert!(metric.get_value(&glean, "store1").is_none());
+
+    // Make sure that the errors have been recorded
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
+
+#[test]
+fn the_accumulate_samples_api_correctly_stores_timing_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Second,
+    );
+
+    // Accumulate the samples. We intentionally do not report
+    // negative values to not trigger error reporting.
+    metric.accumulate_samples_sync(&glean, [1, 2, 3].to_vec());
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    let seconds_to_nanos = 1000 * 1000 * 1000;
+
+    // Check that we got the right sum.
+    assert_eq!(snapshot.sum, 6 * seconds_to_nanos);
+
+    // Check that we got the right number of samples.
+    assert_eq!(snapshot.count, 3);
+
+    // We should get a sample in 3 buckets.
+    // These numbers are a bit magic, but they correspond to
+    // `hist.sample_to_bucket_minimum(i * seconds_to_nanos)` for `i = 1..=3`.
+    assert_eq!(1, snapshot.values[&984625593]);
+    assert_eq!(1, snapshot.values[&1969251187]);
+    assert_eq!(1, snapshot.values[&2784941737]);
+
+    // No errors should be reported.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).is_err());
+}
+
+#[test]
+fn the_accumulate_samples_api_correctly_handles_negative_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    // Accumulate the samples.
+    metric.accumulate_samples_sync(&glean, [-1, 1, 2, 3].to_vec());
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    // Check that we got the right sum.
+    assert_eq!(snapshot.sum, 6);
+
+    // Check that we got the right number of samples.
+    assert_eq!(snapshot.count, 3);
+
+    // We should get a sample in each of the first 3 buckets.
+    assert_eq!(1, snapshot.values[&1]);
+    assert_eq!(1, snapshot.values[&2]);
+    assert_eq!(1, snapshot.values[&3]);
+
+    // 1 error should be reported.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue)
+    );
+}
+
+#[test]
+fn the_accumulate_samples_api_correctly_handles_overflowing_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    // The MAX_SAMPLE_TIME is the same from `metrics/timing_distribution.rs`.
+    const MAX_SAMPLE_TIME: u64 = 1000 * 1000 * 1000 * 60 * 10;
+    let overflowing_val = MAX_SAMPLE_TIME as i64 + 1;
+    // Accumulate the samples.
+    metric.accumulate_samples_sync(&glean, [overflowing_val, 1, 2, 3].to_vec());
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    // Overflowing values are truncated to MAX_SAMPLE_TIME and recorded.
+    assert_eq!(snapshot.sum as u64, MAX_SAMPLE_TIME + 6);
+
+    // Check that we got the right number of samples.
+    assert_eq!(snapshot.count, 4);
+
+    // We should get a sample in each of the first 3 buckets.
+    assert_eq!(1, snapshot.values[&1]);
+    assert_eq!(1, snapshot.values[&2]);
+    assert_eq!(1, snapshot.values[&3]);
+
+    // 1 error should be reported.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
+
+#[test]
+fn large_nanoseconds_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let time = Duration::from_secs(10).as_nanos() as u64;
+    assert!(time > u64::from(u32::max_value()));
+
+    let id = 4u64.into();
+    metric.set_start(id, 0);
+    metric.set_stop_and_accumulate(&glean, id, time);
+
+    let val = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    // Check that we got the right sum and number of samples.
+    assert_eq!(val.sum, time as i64);
+}
+
+#[test]
+fn stopping_non_existing_id_records_an_error() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "non_existing_id".into(),
+            category: "test".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    let id = 3785u64.into();
+    metric.set_stop_and_accumulate(&glean, id, 60);
+
+    // 1 error should be reported.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState)
+    );
+}
+
+#[test]
+fn the_accumulate_raw_samples_api_correctly_stores_timing_values() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Second,
+    );
+
+    let seconds_to_nanos = 1000 * 1000 * 1000;
+    metric.accumulate_raw_samples_nanos_sync(
+        &glean,
+        [seconds_to_nanos, 2 * seconds_to_nanos, 3 * seconds_to_nanos].as_ref(),
+    );
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    // Check that we got the right sum.
+    assert_eq!(snapshot.sum, 6 * seconds_to_nanos as i64);
+
+    // Check that we got the right number of samples.
+    assert_eq!(snapshot.count, 3);
+
+    // We should get a sample in 3 buckets.
+    // These numbers are a bit magic, but they correspond to
+    // `hist.sample_to_bucket_minimum(i * seconds_to_nanos)` for `i = 1..=3`.
+    assert_eq!(1, snapshot.values[&984625593]);
+    assert_eq!(1, snapshot.values[&1969251187]);
+    assert_eq!(1, snapshot.values[&2784941737]);
+
+    // No errors should be reported.
+    assert!(test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidState).is_err());
+}
+
+#[test]
+fn raw_samples_api_error_cases() {
+    let (glean, _t) = new_glean(None);
+
+    let metric = TimingDistributionMetric::new(
+        CommonMetricData {
+            name: "distribution".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::Ping,
+            ..Default::default()
+        },
+        TimeUnit::Nanosecond,
+    );
+
+    // 10minutes in nanoseconds
+    let max_sample_time = 1000 * 1000 * 1000 * 60 * 10;
+
+    metric.accumulate_raw_samples_nanos_sync(
+        &glean,
+        &[
+            0,                   /* rounded up to 1 */
+            1,                   /* valid */
+            max_sample_time + 1, /* larger then the maximum, will record an error and the maximum */
+        ],
+    );
+
+    let snapshot = metric
+        .get_value(&glean, "store1")
+        .expect("Value should be stored");
+
+    // Check that we got the right sum.
+    assert_eq!(snapshot.sum, 2 + max_sample_time as i64);
+
+    // Check that we got the right number of samples.
+    assert_eq!(snapshot.count, 3);
+
+    // We should get a sample in 3 buckets.
+    // These numbers are a bit magic, but they correspond to
+    // `hist.sample_to_bucket_minimum(i * seconds_to_nanos)` for `i = {1, max_sample_time}`.
+    assert_eq!(2, snapshot.values[&1]);
+    assert_eq!(1, snapshot.values[&599512966122]);
+
+    // 1 error should be reported.
+    assert_eq!(
+        Ok(1),
+        test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
+    );
+}
diff --git a/third_party/rust/glean-core/tests/uuid.rs b/third_party/rust/glean-core/tests/uuid.rs
new file mode 100644
index 0000000000..c9d5015a72
--- /dev/null
+++ b/third_party/rust/glean-core/tests/uuid.rs
@@ -0,0 +1,114 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+mod common;
+use crate::common::*;
+
+use serde_json::json;
+
+use glean_core::metrics::*;
+use glean_core::storage::StorageManager;
+use glean_core::{CommonMetricData, Lifetime};
+
+#[test]
+fn uuid_is_generated_and_stored() {
+    let (mut glean, _t) = new_glean(None);
+
+    let uuid: UuidMetric = UuidMetric::new(CommonMetricData {
+        name: "uuid".into(),
+        category: "local".into(),
+        send_in_pings: vec!["core".into()],
+        ..Default::default()
+    });
+
+    uuid.generate_and_set_sync(&glean);
+    let snapshot = glean.snapshot("core", false);
+    assert!(
+        snapshot.contains(r#""local.uuid": ""#),
+        "Snapshot 1: {snapshot}"
+    );
+
+    uuid.generate_and_set_sync(&glean);
+    let snapshot = glean.snapshot("core", false);
+    assert!(
+        snapshot.contains(r#""local.uuid": ""#),
+        "Snapshot 2: {snapshot}"
+    );
+}
+
+#[test]
+fn uuid_serializer_should_correctly_serialize_uuids() {
+    let value = uuid::Uuid::new_v4();
+
+    let (mut tempdir, _) = tempdir();
+
+    {
+        // We give tempdir to the `new_glean` function...
+        let (glean, dir) = new_glean(Some(tempdir));
+        // And then we get it back once that function returns.
+        tempdir = dir;
+
+        let metric = UuidMetric::new(CommonMetricData {
+            name: "uuid_metric".into(),
+            category: "telemetry".into(),
+            send_in_pings: vec!["store1".into()],
+            disabled: false,
+            lifetime: Lifetime::User,
+            ..Default::default()
+        });
+
+        metric.set_from_uuid_sync(&glean, value);
+
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"uuid": {"telemetry.uuid_metric": value.to_string()}}),
+            snapshot
+        );
+    }
+
+    // Make a new Glean instance here, which should force reloading of the data from disk
+    // so we can ensure it persisted, because it has User lifetime
+    {
+        let (glean, _t) = new_glean(Some(tempdir));
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), "store1", true)
+            .unwrap();
+        assert_eq!(
+            json!({"uuid": {"telemetry.uuid_metric": value.to_string()}}),
+            snapshot
+        );
+    }
+}
+
+#[test]
+fn set_properly_sets_the_value_in_all_stores() {
+    let (glean, _t) = new_glean(None);
+    let store_names: Vec<String> = vec!["store1".into(), "store2".into()];
+    let value = uuid::Uuid::new_v4();
+
+    let metric = UuidMetric::new(CommonMetricData {
+        name: "uuid_metric".into(),
+        category: "telemetry".into(),
+        send_in_pings: store_names.clone(),
+        disabled: false,
+        lifetime: Lifetime::Ping,
+        ..Default::default()
+    });
+
+    metric.set_from_uuid_sync(&glean, value);
+
+    // Check that the data was correctly set in each store.
+    for store_name in store_names {
+        let snapshot = StorageManager
+            .snapshot_as_json(glean.storage(), &store_name, true)
+            .unwrap();
+
+        assert_eq!(
+            json!({"uuid": {"telemetry.uuid_metric": value.to_string()}}),
+            snapshot
+        );
+    }
+}