[clang] 24364cd - [clang][CodeComplete] Make completion work after initializer lists

[Kadir Cetinkaya via cfe-commits]

Author: Kadir Cetinkaya
Date: 2020-01-23T15:32:46+01:00
New Revision: 24364cd12bbfa2e58fa74bfb49d4ea85c64c0951

URL: https://github.com/llvm/llvm-project/commit/24364cd12bbfa2e58fa74bfb49d4ea85c64c0951
DIFF: https://github.com/llvm/llvm-project/commit/24364cd12bbfa2e58fa74bfb49d4ea85c64c0951.diff

LOG: [clang][CodeComplete] Make completion work after initializer lists

Summary:
CodeCompletion was not being triggered after successfully parsed
initializer lists, e.g.

```cpp
void foo(int, bool);
void bar() {
  foo({1}^, false);
}
```

CodeCompletion would suggest the function foo as an overload candidate up until
the point marked with `^` but after that point we do not trigger signature help
since parsing succeeds.

This patch handles that case by failing in parsing expression lists whenever we
see a codecompletion token, in addition to getting an invalid subexpression.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73177

Added: 
    

Modified: 
    clang/lib/Parse/ParseExpr.cpp
    clang/test/CodeCompletion/call.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index df8388926db1..ba7525ecf527 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -3128,6 +3128,16 @@ bool Parser::ParseExpressionList(SmallVectorImpl<Expr *> &Exprs,
 
     if (Tok.is(tok::ellipsis))
       Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken());
+    else if (Tok.is(tok::code_completion)) {
+      // There's nothing to suggest in here as we parsed a full expression.
+      // Instead fail and propogate the error since caller might have something
+      // the suggest, e.g. signature help in function call. Note that this is
+      // performed before pushing the \p Expr, so that signature help can report
+      // current argument correctly.
+      SawError = true;
+      cutOffParsing();
+      break;
+    }
     if (Expr.isInvalid()) {
       SkipUntil(tok::comma, tok::r_paren, StopBeforeMatch);
       SawError = true;

diff  --git a/clang/test/CodeCompletion/call.cpp b/clang/test/CodeCompletion/call.cpp
index c57c339cd130..9cba6ae100b3 100644
--- a/clang/test/CodeCompletion/call.cpp
+++ b/clang/test/CodeCompletion/call.cpp
@@ -25,4 +25,10 @@ void test() {
   // RUN: %clang_cc1 -fsyntax-only -code-completion-at=%s:19:13 %s -o - | FileCheck -check-prefix=CHECK-CC2 %s
   // CHECK-CC2-NOT: f(Y y, int ZZ)
   // CHECK-CC2: f(int i, int j, <#int k#>)
+  f({}, 0, 0);
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:28:7 %s -o - | FileCheck -check-prefix=CHECK-CC3 %s
+  // CHECK-CC3: OVERLOAD: [#void#]f()
+  // CHECK-CC3-NEXT: OVERLOAD: [#void#]f(<#X#>)
+  // CHECK-CC3-NEXT: OVERLOAD: [#void#]f(<#int i#>, int j, int k)
+  // CHECK-CC3-NEXT: OVERLOAD: [#void#]f(<#float x#>, float y)
 }