internal: Pin commit of rust-lang/rust for rustc-test metrics

Author: Veykril

crates/rust-analyzer/src/cli/rustc_tests.rs

@@ -276,6 +276,7 @@ impl flags::RustcTests {
     pub fn run(self) -> Result<()> {
         let mut tester = Tester::new()?;
         let walk_dir = WalkDir::new(self.rustc_repo.join("tests/ui"));
+        eprintln!("Running tests for tests/ui");
         for i in walk_dir {
             let i = i?;
             let p = i.into_path();

xtask/src/metrics.rs

@@ -86,7 +86,11 @@ impl Metrics {
     fn measure_rustc_tests(&mut self, sh: &Shell) -> anyhow::Result<()> {
         eprintln!("\nMeasuring rustc tests");
 
-        cmd!(sh, "git clone --depth=1 https://github.com/rust-lang/rust").run()?;
+        cmd!(
+            sh,
+            "git clone --depth=1 --branch 1.76.0 https://github.com/rust-lang/rust.git --single-branch"
+        )
+        .run()?;
 
         let output = cmd!(sh, "./target/release/rust-analyzer rustc-tests ./rust").read()?;
         for (metric, value, unit) in parse_metrics(&output) {