Add rust-analyzer submodule

The current plan is that submodule tracks the `release` branch of
rust-analyzer, which is updated once a week.

rust-analyzer is a workspace (with a virtual manifest), the actual
binary is provide by `crates/rust-analyzer` package.

Note that we intentionally don't add rust-analyzer to `Kind::Test`,
for two reasons.

*First*, at the moment rust-analyzer's test suite does a couple of
things which might not work in the context of rust repository. For
example, it shells out directly to `rustup` and `rustfmt`. So, making
this work requires non-trivial efforts.

*Second*, it seems unlikely that running tests in rust-lang/rust repo
would provide any additional guarantees. rust-analyzer builds with
stable and does not depend on the specifics of the compiler, so
changes to compiler can't break ra, unless they break stability
guarantee. Additionally, rust-analyzer itself is gated on bors, so we
are pretty confident that test suite passes.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs
index b611af54565..b9738894486 100644
--- a/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@ -225,6 +225,7 @@ pub struct Build {
     rust_info: channel::GitInfo,
     cargo_info: channel::GitInfo,
     rls_info: channel::GitInfo,
+    rust_analyzer_info: channel::GitInfo,
     clippy_info: channel::GitInfo,
     miri_info: channel::GitInfo,
     rustfmt_info: channel::GitInfo,
@@ -349,6 +350,8 @@ impl Build {
         let rust_info = channel::GitInfo::new(ignore_git, &src);
         let cargo_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/cargo"));
         let rls_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/rls"));
+        let rust_analyzer_info =
+            channel::GitInfo::new(ignore_git, &src.join("src/tools/rust-analyzer"));
         let clippy_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/clippy"));
         let miri_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/miri"));
         let rustfmt_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/rustfmt"));
@@ -405,6 +408,7 @@ impl Build {
             rust_info,
             cargo_info,
             rls_info,
+            rust_analyzer_info,
             clippy_info,
             miri_info,
             rustfmt_info,
@@ -1034,6 +1038,11 @@ impl Build {
         self.package_vers(&self.release_num("rls"))
     }
 
+    /// Returns the value of `package_vers` above for rust-analyzer
+    fn rust_analyzer_package_vers(&self) -> String {
+        self.package_vers(&self.release_num("rust-analyzer/crates/rust-analyzer"))
+    }
+
     /// Returns the value of `package_vers` above for clippy
     fn clippy_package_vers(&self) -> String {
         self.package_vers(&self.release_num("clippy"))