[clang] [Clang] enhance error recovery with RecoveryExpr for trailing commas in call arguments (PR #114684)

[Haojian Wu via cfe-commits]

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@@ -32,6 +32,26 @@ void test_invalid_call(int s) {
   int var = some_func(undef1);
 }
 
+int some_func2(int a, int b);
+void test_invalid_call_2() {
+  // CHECK:   `-RecoveryExpr {{.*}} 'int' contains-errors
+  // CHECK-NEXT: |-UnresolvedLookupExpr {{.*}} '<overloaded function type>' lvalue (ADL) = 'some_func2'
+  // CHECK-NEXT: `-IntegerLiteral {{.*}} 'int' 1
+  some_func2(1, );
+}
+
+void test_invalid_call_3() {
+  // CHECK:   `-RecoveryExpr {{.*}} 'int' contains-errors
+  // CHECK-NEXT: -UnresolvedLookupExpr {{.*}} '<overloaded function type>' lvalue (ADL) = 'some_func2'
+  some_func2(,);
+}
+
+void test_invalid_call_4() {
+  // CHECK:   `-RecoveryExpr {{.*}} 'int' contains-errors
+  // CHECK-NEXT: -UnresolvedLookupExpr {{.*}} '<overloaded function type>' lvalue (ADL) = 'some_func2'
+  some_func2(,,);
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hokein wrote:

nit: we can bundle all three cases into a single function, as they all tests the trailing comma case. 

Can you also check the `some_func2(,1);` case?

https://github.com/llvm/llvm-project/pull/114684