1 files changed, 19 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/proc-macro-srv-cli/src/main.rs b/src/tools/rust-analyzer/crates/proc-macro-srv-cli/src/main.rs
new file mode 100644
index 000000000..ac9fa9f5a
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-srv-cli/src/main.rs
@@ -0,0 +1,19 @@
+//! A standalone binary for `proc-macro-srv`.
+
+use proc_macro_srv::cli;
+
+fn main() -> std::io::Result<()> {
+    let v = std::env::var("RUST_ANALYZER_INTERNALS_DO_NOT_USE");
+    match v.as_deref() {
+        Ok("this is unstable") => {
+            // very well, if you must
+        }
+        _ => {
+            eprintln!("If you're rust-analyzer, you can use this tool by exporting RUST_ANALYZER_INTERNALS_DO_NOT_USE='this is unstable'.");
+            eprintln!("If not, you probably shouldn't use this tool. But do what you want: I'm an error message, not a cop.");
+            std::process::exit(122);
+        }
+    }
+
+    cli::run()
+}