Auto merge of #17994 - Veykril:proc-macro-srv-from-str-panic, r=Veykril

fix: Fix proc-macro server crashing when parsing a non-lexable string into a TokenStream

We might wanna consider backporting this to beta if that's simple enough to do

Author: bors

crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs

@@ -142,7 +142,13 @@ impl server::TokenStream for RaSpanServer {
         stream.is_empty()
     }
     fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+        Self::TokenStream::from_str(src, self.call_site).unwrap_or_else(|e| {
+            Self::TokenStream::from_str(
+                &format!("compile_error!(\"failed to parse str to token stream: {e}\")"),
+                self.call_site,
+            )
+            .unwrap()
+        })
     }
     fn to_string(&mut self, stream: &Self::TokenStream) -> String {
         stream.to_string()

crates/proc-macro-srv/src/server_impl/token_id.rs

@@ -131,7 +131,13 @@ impl server::TokenStream for TokenIdServer {
         stream.is_empty()
     }
     fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+        Self::TokenStream::from_str(src, self.call_site).unwrap_or_else(|e| {
+            Self::TokenStream::from_str(
+                &format!("compile_error!(\"failed to parse str to token stream: {e}\")"),
+                self.call_site,
+            )
+            .unwrap()
+        })
     }
     fn to_string(&mut self, stream: &Self::TokenStream) -> String {
         stream.to_string()

crates/proc-macro-srv/src/server_impl/token_stream.rs

@@ -131,7 +131,7 @@ pub(super) mod token_stream {
                 call_site,
                 src,
             )
-            .ok_or("lexing error")?;
+            .ok_or_else(|| format!("lexing error: {src}"))?;
 
             Ok(TokenStream::with_subtree(subtree))
         }