Merge #8808

8808: fix: Fix fn proc macro input again r=jonas-schievink a=jonas-schievink

#8806 broke the `TokenMap`, so none of the tokens in fn-like proc macro inputs could be related to the output (presumably this is because of the `clone_for_update`).

This PR instead just sets `delimiter = None;` after the `TokenMap` and `Subtree` are already created.

We should probably have more tests for fn-like proc macros, and consider making the behavior consistent with MBE (which *require* the delimiters to be present).

bors r+

Co-authored-by: Jonas Schievink <[email protected]>

Author: bors[bot]

crates/hir_expand/src/db.rs

@@ -267,7 +267,16 @@ fn parse_macro_expansion(
 
 fn macro_arg(db: &dyn AstDatabase, id: MacroCallId) -> Option<Arc<(tt::Subtree, mbe::TokenMap)>> {
     let arg = db.macro_arg_text(id)?;
-    let (tt, tmap) = mbe::syntax_node_to_token_tree(&SyntaxNode::new_root(arg));
+    let (mut tt, tmap) = mbe::syntax_node_to_token_tree(&SyntaxNode::new_root(arg));
+
+    if let MacroCallId::LazyMacro(id) = id {
+        let loc: MacroCallLoc = db.lookup_intern_macro(id);
+        if loc.def.is_proc_macro() {
+            // proc macros expect their inputs without parentheses, MBEs expect it with them included
+            tt.delimiter = None;
+        }
+    }
+
     Some(Arc::new((tt, tmap)))
 }
 

crates/hir_expand/src/input.rs

@@ -1,9 +1,8 @@
 //! Macro input conditioning.
 
-use parser::SyntaxKind;
 use syntax::{
     ast::{self, AttrsOwner},
-    AstNode, SyntaxElement, SyntaxNode,
+    AstNode, SyntaxNode,
 };
 
 use crate::{
@@ -20,33 +19,7 @@ pub(crate) fn process_macro_input(
     let loc: MacroCallLoc = db.lookup_intern_macro(id);
 
     match loc.kind {
-        MacroCallKind::FnLike { .. } => {
-            if !loc.def.is_proc_macro() {
-                // MBE macros expect the parentheses as part of their input.
-                return node;
-            }
-
-            // The input includes the `(` + `)` delimiter tokens, so remove them before passing this
-            // to the macro.
-            let node = node.clone_for_update();
-            if let Some(SyntaxElement::Token(tkn)) = node.first_child_or_token() {
-                if matches!(
-                    tkn.kind(),
-                    SyntaxKind::L_BRACK | SyntaxKind::L_PAREN | SyntaxKind::L_CURLY
-                ) {
-                    tkn.detach();
-                }
-            }
-            if let Some(SyntaxElement::Token(tkn)) = node.last_child_or_token() {
-                if matches!(
-                    tkn.kind(),
-                    SyntaxKind::R_BRACK | SyntaxKind::R_PAREN | SyntaxKind::R_CURLY
-                ) {
-                    tkn.detach();
-                }
-            }
-            node
-        }
+        MacroCallKind::FnLike { .. } => node,
         MacroCallKind::Derive { derive_attr_index, .. } => {
             let item = match ast::Item::cast(node.clone()) {
                 Some(item) => item,