1 files changed, 46 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/rustc_wrapper.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/rustc_wrapper.rs
new file mode 100644
index 000000000..2f6d4706d
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/rustc_wrapper.rs
@@ -0,0 +1,46 @@
+//! We setup RUSTC_WRAPPER to point to `rust-analyzer` binary itself during the
+//! initial `cargo check`. That way, we avoid checking the actual project, and
+//! only build proc macros and build.rs.
+//!
+//! Code taken from IntelliJ :0)
+//!     https://github.com/intellij-rust/intellij-rust/blob/master/native-helper/src/main.rs
+use std::{
+    ffi::OsString,
+    io,
+    process::{Command, Stdio},
+};
+
+/// ExitCode/ExitStatus are impossible to create :(.
+pub(crate) struct ExitCode(pub(crate) Option<i32>);
+
+pub(crate) fn run_rustc_skipping_cargo_checking(
+    rustc_executable: OsString,
+    args: Vec<OsString>,
+) -> io::Result<ExitCode> {
+    let is_cargo_check = args.iter().any(|arg| {
+        let arg = arg.to_string_lossy();
+        // `cargo check` invokes `rustc` with `--emit=metadata` argument.
+        //
+        // https://doc.rust-lang.org/rustc/command-line-arguments.html#--emit-specifies-the-types-of-output-files-to-generate
+        // link —     Generates the crates specified by --crate-type. The default
+        //            output filenames depend on the crate type and platform. This
+        //            is the default if --emit is not specified.
+        // metadata — Generates a file containing metadata about the crate.
+        //            The default output filename is CRATE_NAME.rmeta.
+        arg.starts_with("--emit=") && arg.contains("metadata") && !arg.contains("link")
+    });
+    if is_cargo_check {
+        return Ok(ExitCode(Some(0)));
+    }
+    run_rustc(rustc_executable, args)
+}
+
+fn run_rustc(rustc_executable: OsString, args: Vec<OsString>) -> io::Result<ExitCode> {
+    let mut child = Command::new(rustc_executable)
+        .args(args)
+        .stdin(Stdio::inherit())
+        .stdout(Stdio::inherit())
+        .stderr(Stdio::inherit())
+        .spawn()?;
+    Ok(ExitCode(child.wait()?.code()))
+}