[WATParser] Skip identifiers in ParseDeclsCtx::skipFunctionBody

Without taking identifiers in ParseDeclsCtx::skipFunctionBody, an identifier starting with a block or indirect call keyword (such as $block or $call_indirect) would have only its leading '$' consumed by in.take(1) and then be misparsed as a keyword on the next iteration, adding a spurious implicit function type.

Author: tlively

src/parser/context-decls.cpp

@@ -321,6 +321,9 @@ bool ParseDeclsCtx::skipFunctionBody() {
       --depth;
       continue;
     }
+    if (in.takeID()) {
+      continue;
+    }
     if (auto kw = in.takeKeyword()) {
       if (*kw == "block"sv || *kw == "loop"sv || *kw == "if"sv ||
           *kw == "try"sv || *kw == "try_table"sv) {

test/lit/blocktype.wast

@@ -37,19 +37,34 @@
  )
 
  ;; CHECK:      (func $f2 (type $f2) (result (ref $f2) (ref $f1))
- ;; CHECK-NEXT:  (loop $l (type $f2) (result (ref $f2) (ref $f1))
- ;; CHECK-NEXT:   (call $f2)
+ ;; CHECK-NEXT:  (loop $block (type $f2) (result (ref $f2) (ref $f1))
+ ;; CHECK-NEXT:   (br $block)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  ;; RTRIP:      (func $f2 (type $f2) (result (ref $f2) (ref $f1))
- ;; RTRIP-NEXT:  (loop (type $f2) (result (ref $f2) (ref $f1))
- ;; RTRIP-NEXT:   (call $f2)
+ ;; RTRIP-NEXT:  (loop $label (type $f2) (result (ref $f2) (ref $f1))
+ ;; RTRIP-NEXT:   (br $label)
  ;; RTRIP-NEXT:  )
  ;; RTRIP-NEXT: )
  (func $f2 (type $f2) (result (ref $f2) (ref $f1))
   ;; This block will be emitted with type $f2
-  (loop $l (type $block2) (result (ref $f2) (ref $f1))
-   (call $f2)
+  (loop $block (type $block2) (result (ref $f2) (ref $f1))
+   (br $block)
+  )
+ )
+
+ ;; CHECK:      (func $f3 (type $2) (result i32)
+ ;; CHECK-NEXT:  (i32.const 0)
+ ;; CHECK-NEXT: )
+ ;; RTRIP:      (func $f3 (type $2) (result i32)
+ ;; RTRIP-NEXT:  (i32.const 0)
+ ;; RTRIP-NEXT: )
+ (func $f3 (result i32)
+  ;; Type index 4 is the implicit (func (result i32)) from $f3's signature,
+  ;; unless $block in $f2 was parsed as a block keyword and created a
+  ;; spurious () -> () implicit type at index 4.
+  (block (type 4) (result i32)
+   (i32.const 0)
   )
  )
 )