Add version command to proc-macro-srv

crates/proc-macro-srv-cli/src/main.rs

@@ -2,11 +2,13 @@
 //! Driver for proc macro server
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 #![cfg_attr(not(feature = "sysroot-abi"), allow(unused_crate_dependencies))]
-#![allow(clippy::print_stderr)]
+#![allow(clippy::print_stdout, clippy::print_stderr)]
 
 #[cfg(feature = "in-rust-tree")]
 extern crate rustc_driver as _;
 
+mod version;
+
 #[cfg(any(feature = "sysroot-abi", rust_analyzer))]
 mod main_loop;
 use clap::{Command, ValueEnum};
@@ -25,12 +27,22 @@ fn main() -> std::io::Result<()> {
         std::process::exit(122);
     }
     let matches = Command::new("proc-macro-srv")
-        .args(&[clap::Arg::new("format")
-            .long("format")
-            .action(clap::ArgAction::Set)
-            .default_value("json")
-            .value_parser(clap::builder::EnumValueParser::<ProtocolFormat>::new())])
+        .args(&[
+            clap::Arg::new("format")
+                .long("format")
+                .action(clap::ArgAction::Set)
+                .default_value("json")
+                .value_parser(clap::builder::EnumValueParser::<ProtocolFormat>::new()),
+            clap::Arg::new("version")
+                .long("version")
+                .action(clap::ArgAction::SetTrue)
+                .help("Prints the version of the proc-macro-srv"),
+        ])
         .get_matches();
+    if matches.get_flag("version") {
+        println!("rust-analyzer-proc-macro-srv {}", version::version());
+        return Ok(());
+    }
     let &format =
         matches.get_one::<ProtocolFormat>("format").expect("format value should always be present");
     run(format)

crates/proc-macro-srv-cli/src/version.rs

@@ -0,0 +1,58 @@
+//! Code for representing rust-analyzer's release version number.
+#![expect(dead_code)]
+
+use std::fmt;
+
+/// Information about the git repository where rust-analyzer was built from.
+pub(crate) struct CommitInfo {
+    pub(crate) short_commit_hash: &'static str,
+    pub(crate) commit_hash: &'static str,
+    pub(crate) commit_date: &'static str,
+}
+
+/// Cargo's version.
+pub(crate) struct VersionInfo {
+    /// rust-analyzer's version, such as "1.57.0", "1.58.0-beta.1", "1.59.0-nightly", etc.
+    pub(crate) version: &'static str,
+    /// The release channel we were built for (stable/beta/nightly/dev).
+    ///
+    /// `None` if not built via bootstrap.
+    pub(crate) release_channel: Option<&'static str>,
+    /// Information about the Git repository we may have been built from.
+    ///
+    /// `None` if not built from a git repo.
+    pub(crate) commit_info: Option<CommitInfo>,
+}
+
+impl fmt::Display for VersionInfo {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.version)?;
+
+        if let Some(ci) = &self.commit_info {
+            write!(f, " ({} {})", ci.short_commit_hash, ci.commit_date)?;
+        };
+        Ok(())
+    }
+}
+
+/// Returns information about cargo's version.
+pub(crate) const fn version() -> VersionInfo {
+    let version = match option_env!("CFG_RELEASE") {
+        Some(x) => x,
+        None => "0.0.0",
+    };
+
+    let release_channel = option_env!("CFG_RELEASE_CHANNEL");
+    let commit_info = match (
+        option_env!("RA_COMMIT_SHORT_HASH"),
+        option_env!("RA_COMMIT_HASH"),
+        option_env!("RA_COMMIT_DATE"),
+    ) {
+        (Some(short_commit_hash), Some(commit_hash), Some(commit_date)) => {
+            Some(CommitInfo { short_commit_hash, commit_hash, commit_date })
+        }
+        _ => None,
+    };
+
+    VersionInfo { version, release_channel, commit_info }
+}