5 files changed, 347 insertions, 0 deletions
diff --git a/tools/code-coverage/tests/xpcshell/head.js b/tools/code-coverage/tests/xpcshell/head.js
new file mode 100644
index 0000000000..3642c5794c
--- /dev/null
+++ b/tools/code-coverage/tests/xpcshell/head.js
@@ -0,0 +1,100 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+
+function getFiles() {
+  // This is the directory where gcov is emitting the gcda files.
+  const jsCoveragePath = Services.env.get("JS_CODE_COVERAGE_OUTPUT_DIR");
+
+  const jsCoverageDir = Cc["@mozilla.org/file/local;1"].createInstance(
+    Ci.nsIFile
+  );
+  jsCoverageDir.initWithPath(jsCoveragePath);
+
+  let files = [];
+
+  let entries = jsCoverageDir.directoryEntries;
+  while (entries.hasMoreElements()) {
+    files.push(entries.nextFile);
+  }
+
+  return files;
+}
+
+function diffFiles(files_after, files_before) {
+  let files_before_set = new Set(files_before.map(file => file.leafName));
+  return files_after.filter(file => !files_before_set.has(file.leafName));
+}
+
+const BASENAME_RE = new RegExp("([^/\\\\]+)$");
+
+function parseRecords(files) {
+  let records = new Map();
+
+  for (let file of files) {
+    const lines = Cu.readUTF8File(file).split("\n");
+    let currentSF = null;
+
+    for (let line of lines) {
+      let [recordType, ...recordContent] = line.split(":");
+      recordContent = recordContent.join(":");
+
+      switch (recordType) {
+        case "FNDA": {
+          if (currentSF == null) {
+            throw new Error("SF missing");
+          }
+
+          let [hits, name] = recordContent.split(",");
+          currentSF.push({
+            type: "FNDA",
+            hits,
+            name,
+          });
+          break;
+        }
+
+        case "FN": {
+          if (currentSF == null) {
+            throw new Error("SF missing");
+          }
+
+          let name = recordContent.split(",")[1];
+          currentSF.push({
+            type: "FN",
+            name,
+          });
+          break;
+        }
+
+        case "SF": {
+          if (
+            recordContent.startsWith("resource:") ||
+            recordContent.startsWith("chrome:")
+          ) {
+            recordContent = recordContent.split("/").at(-1);
+          } else {
+            if (AppConstants.platform == "win") {
+              recordContent = recordContent.replace(/\//g, "\\");
+            }
+            const match = BASENAME_RE.exec(recordContent);
+            if (match.length) {
+              recordContent = match[0];
+            }
+          }
+
+          currentSF = [];
+
+          records.set(recordContent, currentSF);
+          break;
+        }
+      }
+    }
+  }
+
+  return records;
+}
diff --git a/tools/code-coverage/tests/xpcshell/support.js b/tools/code-coverage/tests/xpcshell/support.js
new file mode 100644
index 0000000000..9189427111
--- /dev/null
+++ b/tools/code-coverage/tests/xpcshell/support.js
@@ -0,0 +1,5 @@
+function test_code_coverage_func2() {
+  return 22;
+}
+
+test_code_coverage_func2();
diff --git a/tools/code-coverage/tests/xpcshell/test_basic.js b/tools/code-coverage/tests/xpcshell/test_basic.js
new file mode 100644
index 0000000000..9523a37ca2
--- /dev/null
+++ b/tools/code-coverage/tests/xpcshell/test_basic.js
@@ -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 http://mozilla.org/MPL/2.0/. */
+
+function test_code_coverage_func1() {
+  return 22;
+}
+
+function test_code_coverage_func2() {
+  return 22;
+}
+
+async function run_test() {
+  do_test_pending();
+
+  Assert.ok("@mozilla.org/tools/code-coverage;1" in Cc);
+
+  const codeCoverageCc = Cc["@mozilla.org/tools/code-coverage;1"];
+  Assert.ok(!!codeCoverageCc);
+
+  const codeCoverage = codeCoverageCc.getService(Ci.nsICodeCoverage);
+  Assert.ok(!!codeCoverage);
+
+  const files_orig = getFiles();
+
+  test_code_coverage_func1();
+
+  // Flush counters for the first time, we should see this function executed, but test_code_coverage_func not executed.
+  await codeCoverage.flushCounters();
+
+  const first_flush_files = getFiles();
+  const first_flush_records = parseRecords(
+    diffFiles(first_flush_files, files_orig)
+  );
+
+  Assert.ok(first_flush_records.has("test_basic.js"));
+  let fnRecords = first_flush_records
+    .get("test_basic.js")
+    .filter(record => record.type == "FN");
+  let fndaRecords = first_flush_records
+    .get("test_basic.js")
+    .filter(record => record.type == "FNDA");
+  Assert.ok(fnRecords.some(record => record.name == "top-level"));
+  Assert.ok(fnRecords.some(record => record.name == "run_test"));
+  Assert.ok(
+    fnRecords.some(record => record.name == "test_code_coverage_func1")
+  );
+  Assert.ok(
+    fndaRecords.some(record => record.name == "run_test" && record.hits == 1)
+  );
+  Assert.ok(
+    !fndaRecords.some(record => record.name == "run_test" && record.hits != 1)
+  );
+  Assert.ok(
+    fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits == 1
+    )
+  );
+  Assert.ok(
+    !fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits != 1
+    )
+  );
+  Assert.ok(
+    !fndaRecords.some(record => record.name == "test_code_coverage_func2")
+  );
+
+  test_code_coverage_func2();
+
+  // Flush counters for the second time, we should see this function not executed, but test_code_coverage_func executed.
+  await codeCoverage.flushCounters();
+
+  const second_flush_files = getFiles();
+  const second_flush_records = parseRecords(
+    diffFiles(second_flush_files, first_flush_files)
+  );
+
+  Assert.ok(second_flush_records.has("test_basic.js"));
+  fnRecords = second_flush_records
+    .get("test_basic.js")
+    .filter(record => record.type == "FN");
+  fndaRecords = second_flush_records
+    .get("test_basic.js")
+    .filter(record => record.type == "FNDA");
+  Assert.ok(fnRecords.some(record => record.name == "top-level"));
+  Assert.ok(fnRecords.some(record => record.name == "run_test"));
+  Assert.ok(
+    fnRecords.some(record => record.name == "test_code_coverage_func1")
+  );
+  Assert.ok(
+    fnRecords.some(record => record.name == "test_code_coverage_func2")
+  );
+  Assert.ok(
+    fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits == 0
+    )
+  );
+  Assert.ok(
+    !fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits != 0
+    )
+  );
+  Assert.ok(
+    fndaRecords.some(
+      record => record.name == "test_code_coverage_func2" && record.hits == 1
+    )
+  );
+  Assert.ok(
+    !fndaRecords.some(
+      record => record.name == "test_code_coverage_func2" && record.hits != 1
+    )
+  );
+
+  do_test_finished();
+}
diff --git a/tools/code-coverage/tests/xpcshell/test_basic_child_and_parent.js b/tools/code-coverage/tests/xpcshell/test_basic_child_and_parent.js
new file mode 100644
index 0000000000..f074c20776
--- /dev/null
+++ b/tools/code-coverage/tests/xpcshell/test_basic_child_and_parent.js
@@ -0,0 +1,120 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+function test_code_coverage_func1() {
+  return 22;
+}
+
+async function run_test() {
+  do_load_child_test_harness();
+  do_test_pending();
+
+  const codeCoverage = Cc["@mozilla.org/tools/code-coverage;1"].getService(
+    Ci.nsICodeCoverage
+  );
+
+  const files_orig = getFiles();
+
+  test_code_coverage_func1();
+
+  await codeCoverage.flushCounters();
+
+  const first_flush_files = getFiles();
+  const first_flush_records = parseRecords(
+    diffFiles(first_flush_files, files_orig)
+  );
+
+  Assert.ok(first_flush_records.has("test_basic_child_and_parent.js"));
+  Assert.ok(!first_flush_records.has("support.js"));
+  let fnRecords = first_flush_records
+    .get("test_basic_child_and_parent.js")
+    .filter(record => record.type == "FN");
+  let fndaRecords = first_flush_records
+    .get("test_basic_child_and_parent.js")
+    .filter(record => record.type == "FNDA");
+  Assert.ok(fnRecords.some(record => record.name == "top-level"));
+  Assert.ok(fnRecords.some(record => record.name == "run_test"));
+  Assert.ok(
+    fnRecords.some(record => record.name == "test_code_coverage_func1")
+  );
+  Assert.ok(
+    fndaRecords.some(record => record.name == "run_test" && record.hits == 1)
+  );
+  Assert.ok(
+    !fndaRecords.some(record => record.name == "run_test" && record.hits != 1)
+  );
+  Assert.ok(
+    fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits == 1
+    )
+  );
+  Assert.ok(
+    !fndaRecords.some(
+      record => record.name == "test_code_coverage_func1" && record.hits != 1
+    )
+  );
+
+  sendCommand("load('support.js');", async function () {
+    await codeCoverage.flushCounters();
+
+    const second_flush_files = getFiles();
+    const second_flush_records = parseRecords(
+      diffFiles(second_flush_files, first_flush_files)
+    );
+
+    Assert.ok(second_flush_records.has("test_basic_child_and_parent.js"));
+    fnRecords = second_flush_records
+      .get("test_basic_child_and_parent.js")
+      .filter(record => record.type == "FN");
+    fndaRecords = second_flush_records
+      .get("test_basic_child_and_parent.js")
+      .filter(record => record.type == "FNDA");
+    Assert.ok(fnRecords.some(record => record.name == "top-level"));
+    Assert.ok(fnRecords.some(record => record.name == "run_test"));
+    Assert.ok(
+      fnRecords.some(record => record.name == "test_code_coverage_func1")
+    );
+    Assert.ok(
+      fndaRecords.some(
+        record => record.name == "test_code_coverage_func1" && record.hits == 0
+      )
+    );
+    Assert.ok(
+      !fndaRecords.some(
+        record => record.name == "test_code_coverage_func1" && record.hits != 0
+      )
+    );
+    Assert.ok(second_flush_records.has("support.js"));
+    fnRecords = second_flush_records
+      .get("support.js")
+      .filter(record => record.type == "FN");
+    fndaRecords = second_flush_records
+      .get("support.js")
+      .filter(record => record.type == "FNDA");
+    Assert.ok(fnRecords.some(record => record.name == "top-level"));
+    Assert.ok(
+      fnRecords.some(record => record.name == "test_code_coverage_func2")
+    );
+    Assert.ok(
+      fndaRecords.some(record => record.name == "top-level" && record.hits == 1)
+    );
+    Assert.ok(
+      !fndaRecords.some(
+        record => record.name == "top-level" && record.hits != 1
+      )
+    );
+    Assert.ok(
+      fndaRecords.some(
+        record => record.name == "test_code_coverage_func2" && record.hits == 1
+      )
+    );
+    Assert.ok(
+      !fndaRecords.some(
+        record => record.name == "test_code_coverage_func2" && record.hits != 1
+      )
+    );
+
+    do_test_finished();
+  });
+}
diff --git a/tools/code-coverage/tests/xpcshell/xpcshell.toml b/tools/code-coverage/tests/xpcshell/xpcshell.toml
new file mode 100644
index 0000000000..e1aacfeada
--- /dev/null
+++ b/tools/code-coverage/tests/xpcshell/xpcshell.toml
@@ -0,0 +1,7 @@
+[DEFAULT]
+head = "head.js"
+support-files = ["support.js"]
+
+["test_basic.js"]
+
+["test_basic_child_and_parent.js"]