1 files changed, 284 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/ide-db/src/tests/sourcegen_lints.rs b/src/tools/rust-analyzer/crates/ide-db/src/tests/sourcegen_lints.rs
new file mode 100644
index 000000000..5042f6d81
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/ide-db/src/tests/sourcegen_lints.rs
@@ -0,0 +1,284 @@
+//! Generates descriptors structure for unstable feature from Unstable Book
+use std::{borrow::Cow, fs, path::Path};
+
+use itertools::Itertools;
+use stdx::format_to;
+use test_utils::project_root;
+use xshell::{cmd, Shell};
+
+/// This clones rustc repo, and so is not worth to keep up-to-date. We update
+/// manually by un-ignoring the test from time to time.
+#[test]
+#[ignore]
+fn sourcegen_lint_completions() {
+    let sh = &Shell::new().unwrap();
+
+    let rust_repo = project_root().join("./target/rust");
+    if !rust_repo.exists() {
+        cmd!(sh, "git clone --depth=1 https://github.com/rust-lang/rust {rust_repo}")
+            .run()
+            .unwrap();
+    }
+
+    let mut contents = String::from(
+        r"
+#[derive(Clone)]
+pub struct Lint {
+    pub label: &'static str,
+    pub description: &'static str,
+}
+pub struct LintGroup {
+    pub lint: Lint,
+    pub children: &'static [&'static str],
+}
+",
+    );
+
+    generate_lint_descriptor(sh, &mut contents);
+    contents.push('\n');
+
+    generate_feature_descriptor(&mut contents, &rust_repo.join("src/doc/unstable-book/src"));
+    contents.push('\n');
+
+    let lints_json = project_root().join("./target/clippy_lints.json");
+    cmd!(
+        sh,
+        "curl https://rust-lang.github.io/rust-clippy/master/lints.json --output {lints_json}"
+    )
+    .run()
+    .unwrap();
+    generate_descriptor_clippy(&mut contents, &lints_json);
+
+    let contents = sourcegen::add_preamble("sourcegen_lints", sourcegen::reformat(contents));
+
+    let destination = project_root().join("crates/ide_db/src/generated/lints.rs");
+    sourcegen::ensure_file_contents(destination.as_path(), &contents);
+}
+
+fn generate_lint_descriptor(sh: &Shell, buf: &mut String) {
+    // FIXME: rustdoc currently requires an input file for -Whelp cc https://github.com/rust-lang/rust/pull/88831
+    let file = project_root().join(file!());
+    let stdout = cmd!(sh, "rustdoc -W help {file}").read().unwrap();
+    let start_lints = stdout.find("----  -------  -------").unwrap();
+    let start_lint_groups = stdout.find("----  ---------").unwrap();
+    let start_lints_rustdoc =
+        stdout.find("Lint checks provided by plugins loaded by this crate:").unwrap();
+    let start_lint_groups_rustdoc =
+        stdout.find("Lint groups provided by plugins loaded by this crate:").unwrap();
+
+    buf.push_str(r#"pub const DEFAULT_LINTS: &[Lint] = &["#);
+    buf.push('\n');
+
+    let lints = stdout[start_lints..].lines().skip(1).take_while(|l| !l.is_empty()).map(|line| {
+        let (name, rest) = line.trim().split_once(char::is_whitespace).unwrap();
+        let (_default_level, description) = rest.trim().split_once(char::is_whitespace).unwrap();
+        (name.trim(), Cow::Borrowed(description.trim()), vec![])
+    });
+    let lint_groups =
+        stdout[start_lint_groups..].lines().skip(1).take_while(|l| !l.is_empty()).map(|line| {
+            let (name, lints) = line.trim().split_once(char::is_whitespace).unwrap();
+            (
+                name.trim(),
+                format!("lint group for: {}", lints.trim()).into(),
+                lints
+                    .split_ascii_whitespace()
+                    .map(|s| s.trim().trim_matches(',').replace('-', "_"))
+                    .collect(),
+            )
+        });
+
+    let lints = lints
+        .chain(lint_groups)
+        .sorted_by(|(ident, ..), (ident2, ..)| ident.cmp(ident2))
+        .collect::<Vec<_>>();
+    for (name, description, ..) in &lints {
+        push_lint_completion(buf, &name.replace('-', "_"), description);
+    }
+    buf.push_str("];\n");
+    buf.push_str(r#"pub const DEFAULT_LINT_GROUPS: &[LintGroup] = &["#);
+    for (name, description, children) in &lints {
+        if !children.is_empty() {
+            // HACK: warnings is emitted with a general description, not with its members
+            if name == &"warnings" {
+                push_lint_group(buf, name, description, &Vec::new());
+                continue;
+            }
+            push_lint_group(buf, &name.replace('-', "_"), description, children);
+        }
+    }
+    buf.push('\n');
+    buf.push_str("];\n");
+
+    // rustdoc
+
+    buf.push('\n');
+    buf.push_str(r#"pub const RUSTDOC_LINTS: &[Lint] = &["#);
+    buf.push('\n');
+
+    let lints_rustdoc =
+        stdout[start_lints_rustdoc..].lines().skip(2).take_while(|l| !l.is_empty()).map(|line| {
+            let (name, rest) = line.trim().split_once(char::is_whitespace).unwrap();
+            let (_default_level, description) =
+                rest.trim().split_once(char::is_whitespace).unwrap();
+            (name.trim(), Cow::Borrowed(description.trim()), vec![])
+        });
+    let lint_groups_rustdoc =
+        stdout[start_lint_groups_rustdoc..].lines().skip(2).take_while(|l| !l.is_empty()).map(
+            |line| {
+                let (name, lints) = line.trim().split_once(char::is_whitespace).unwrap();
+                (
+                    name.trim(),
+                    format!("lint group for: {}", lints.trim()).into(),
+                    lints
+                        .split_ascii_whitespace()
+                        .map(|s| s.trim().trim_matches(',').replace('-', "_"))
+                        .collect(),
+                )
+            },
+        );
+
+    let lints_rustdoc = lints_rustdoc
+        .chain(lint_groups_rustdoc)
+        .sorted_by(|(ident, ..), (ident2, ..)| ident.cmp(ident2))
+        .collect::<Vec<_>>();
+
+    for (name, description, ..) in &lints_rustdoc {
+        push_lint_completion(buf, &name.replace('-', "_"), description)
+    }
+    buf.push_str("];\n");
+
+    buf.push_str(r#"pub const RUSTDOC_LINT_GROUPS: &[LintGroup] = &["#);
+    for (name, description, children) in &lints_rustdoc {
+        if !children.is_empty() {
+            push_lint_group(buf, &name.replace('-', "_"), description, children);
+        }
+    }
+    buf.push('\n');
+    buf.push_str("];\n");
+}
+
+fn generate_feature_descriptor(buf: &mut String, src_dir: &Path) {
+    let mut features = ["language-features", "library-features"]
+        .into_iter()
+        .flat_map(|it| sourcegen::list_files(&src_dir.join(it)))
+        .filter(|path| {
+            // Get all `.md ` files
+            path.extension().unwrap_or_default().to_str().unwrap_or_default() == "md"
+        })
+        .map(|path| {
+            let feature_ident = path.file_stem().unwrap().to_str().unwrap().replace('-', "_");
+            let doc = fs::read_to_string(path).unwrap();
+            (feature_ident, doc)
+        })
+        .collect::<Vec<_>>();
+    features.sort_by(|(feature_ident, _), (feature_ident2, _)| feature_ident.cmp(feature_ident2));
+
+    buf.push_str(r#"pub const FEATURES: &[Lint] = &["#);
+    for (feature_ident, doc) in features.into_iter() {
+        push_lint_completion(buf, &feature_ident, &doc)
+    }
+    buf.push('\n');
+    buf.push_str("];\n");
+}
+
+#[derive(Default)]
+struct ClippyLint {
+    help: String,
+    id: String,
+}
+
+fn unescape(s: &str) -> String {
+    s.replace(r#"\""#, "").replace(r#"\n"#, "\n").replace(r#"\r"#, "")
+}
+
+fn generate_descriptor_clippy(buf: &mut String, path: &Path) {
+    let file_content = std::fs::read_to_string(path).unwrap();
+    let mut clippy_lints: Vec<ClippyLint> = Vec::new();
+    let mut clippy_groups: std::collections::BTreeMap<String, Vec<String>> = Default::default();
+
+    for line in file_content.lines().map(|line| line.trim()) {
+        if let Some(line) = line.strip_prefix(r#""id": ""#) {
+            let clippy_lint = ClippyLint {
+                id: line.strip_suffix(r#"","#).expect("should be suffixed by comma").into(),
+                help: String::new(),
+            };
+            clippy_lints.push(clippy_lint)
+        } else if let Some(line) = line.strip_prefix(r#""group": ""#) {
+            if let Some(group) = line.strip_suffix("\",") {
+                clippy_groups
+                    .entry(group.to_owned())
+                    .or_default()
+                    .push(clippy_lints.last().unwrap().id.clone());
+            }
+        } else if let Some(line) = line.strip_prefix(r#""docs": ""#) {
+            let prefix_to_strip = r#" ### What it does"#;
+            let line = match line.strip_prefix(prefix_to_strip) {
+                Some(line) => line,
+                None => {
+                    eprintln!("unexpected clippy prefix for {}", clippy_lints.last().unwrap().id);
+                    continue;
+                }
+            };
+            // Only take the description, any more than this is a lot of additional data we would embed into the exe
+            // which seems unnecessary
+            let up_to = line.find(r#"###"#).expect("no second section found?");
+            let line = &line[..up_to];
+
+            let clippy_lint = clippy_lints.last_mut().expect("clippy lint must already exist");
+            clippy_lint.help = unescape(line).trim().to_string();
+        }
+    }
+    clippy_lints.sort_by(|lint, lint2| lint.id.cmp(&lint2.id));
+
+    buf.push_str(r#"pub const CLIPPY_LINTS: &[Lint] = &["#);
+    buf.push('\n');
+    for clippy_lint in clippy_lints.into_iter() {
+        let lint_ident = format!("clippy::{}", clippy_lint.id);
+        let doc = clippy_lint.help;
+        push_lint_completion(buf, &lint_ident, &doc);
+    }
+    buf.push_str("];\n");
+
+    buf.push_str(r#"pub const CLIPPY_LINT_GROUPS: &[LintGroup] = &["#);
+    for (id, children) in clippy_groups {
+        let children = children.iter().map(|id| format!("clippy::{}", id)).collect::<Vec<_>>();
+        if !children.is_empty() {
+            let lint_ident = format!("clippy::{}", id);
+            let description = format!("lint group for: {}", children.iter().join(", "));
+            push_lint_group(buf, &lint_ident, &description, &children);
+        }
+    }
+    buf.push('\n');
+    buf.push_str("];\n");
+}
+
+fn push_lint_completion(buf: &mut String, label: &str, description: &str) {
+    format_to!(
+        buf,
+        r###"    Lint {{
+        label: "{}",
+        description: r##"{}"##,
+    }},"###,
+        label,
+        description,
+    );
+}
+
+fn push_lint_group(buf: &mut String, label: &str, description: &str, children: &[String]) {
+    buf.push_str(
+        r###"    LintGroup {
+        lint:
+        "###,
+    );
+
+    push_lint_completion(buf, label, description);
+
+    let children = format!("&[{}]", children.iter().map(|it| format!("\"{}\"", it)).join(", "));
+    format_to!(
+        buf,
+        r###"
+        children: {},
+        }},"###,
+        children,
+    );
+}