From a130cf8ae8ab56ba1cfa7edc52b637c9d0c3fd38 Mon Sep 17 00:00:00 2001
From: Ilya Golovenko <ilya.golovenko@huawei.com>
Date: Thu, 16 Jul 2020 12:47:44 +0200
Subject: [PATCH] [clang] Fix printing of lambdas with capture expressions

Patch by @walrus !

Reviewers: lattner, kadircet

Reviewed By: kadircet

Subscribers: riccibruno, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83855
---
 clang/lib/AST/StmtPrinter.cpp         | 19 +++++++++++++++++--
 clang/test/AST/ast-printer-lambda.cpp | 20 ++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/clang/lib/AST/StmtPrinter.cpp b/clang/lib/AST/StmtPrinter.cpp
index f797f5f..ea16002 100644
--- a/clang/lib/AST/StmtPrinter.cpp
+++ b/clang/lib/AST/StmtPrinter.cpp
@@ -2005,8 +2005,23 @@ void StmtPrinter::VisitLambdaExpr(LambdaExpr *Node) {
     if (C->isPackExpansion())
       OS << "...";
 
-    if (Node->isInitCapture(C))
-      PrintExpr(C->getCapturedVar()->getInit());
+    if (Node->isInitCapture(C)) {
+      VarDecl *D = C->getCapturedVar();
+
+      llvm::StringRef Pre;
+      llvm::StringRef Post;
+      if (D->getInitStyle() == VarDecl::CallInit &&
+          !isa<ParenListExpr>(D->getInit())) {
+        Pre = "(";
+        Post = ")";
+      } else if (D->getInitStyle() == VarDecl::CInit) {
+        Pre = " = ";
+      }
+
+      OS << Pre;
+      PrintExpr(D->getInit());
+      OS << Post;
+    }
   }
   OS << ']';
 
diff --git a/clang/test/AST/ast-printer-lambda.cpp b/clang/test/AST/ast-printer-lambda.cpp
index 27a361d..08f1ff5 100644
--- a/clang/test/AST/ast-printer-lambda.cpp
+++ b/clang/test/AST/ast-printer-lambda.cpp
@@ -16,6 +16,18 @@ void test1(int i, T... t) {
   //CHECK: [&] {
 }
 {
+  auto lambda = [k{i}] {};
+  //CHECK: [k{i}] {
+}
+{
+  auto lambda = [k(i)] {};
+  //CHECK: [k(i)] {
+}
+{
+  auto lambda = [k = i] {};
+  //CHECK: [k = i] {
+}
+{
   auto lambda = [t..., i]{};
   //CHECK: [t..., i] {
 }
@@ -31,6 +43,14 @@ void test1(int i, T... t) {
   auto lambda = [t..., this]{};
   //CHECK: [t..., this] {
 }
+{
+  auto lambda = [k(t...)] {};
+  //CHECK: [k(t...)] {
+}
+{
+  auto lambda = [k{t...}] {};
+  //CHECK: [k{t...}] {
+}
 }
 
 };
\ No newline at end of file
-- 
2.7.4