From 45b6ca5cd604d9dc0f957a5d80724acd54766f19 Mon Sep 17 00:00:00 2001
From: Yitzhak Mandelbaum <yitzhakm@google.com>
Date: Tue, 17 Sep 2019 15:10:39 +0000
Subject: [PATCH] [clang-format] Fix cleanup of `AnnotatedLine` to include
 children nodes.

Summary:
AnnotatedLine has a tree structure, and things like the body of a lambda will be
a child of the lambda expression. For example,

    [&]() { foo(a); };

will have an AnnotatedLine with a child:

    [&]() {};
     '- foo(a);

Currently, when the `Cleaner` class analyzes the affected lines, it does not
cleanup the lines' children nodes, which results in missed cleanup
opportunities, like the lambda body in the example above.

This revision extends the algorithm to visit children, thereby fixing the above problem.

Patch by Eric Li.

Reviewers: krasimir

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67659

llvm-svn: 372129
---
 clang/lib/Format/Format.cpp            | 29 ++++++++++++++++++-----------
 clang/unittests/Format/CleanupTest.cpp |  9 +++++++--
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 81fdab4..801daf1 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -1417,22 +1417,29 @@ public:
 
     checkEmptyNamespace(AnnotatedLines);
 
-    for (auto &Line : AnnotatedLines) {
-      if (Line->Affected) {
-        cleanupRight(Line->First, tok::comma, tok::comma);
-        cleanupRight(Line->First, TT_CtorInitializerColon, tok::comma);
-        cleanupRight(Line->First, tok::l_paren, tok::comma);
-        cleanupLeft(Line->First, tok::comma, tok::r_paren);
-        cleanupLeft(Line->First, TT_CtorInitializerComma, tok::l_brace);
-        cleanupLeft(Line->First, TT_CtorInitializerColon, tok::l_brace);
-        cleanupLeft(Line->First, TT_CtorInitializerColon, tok::equal);
-      }
-    }
+    for (auto *Line : AnnotatedLines)
+      cleanupLine(Line);
 
     return {generateFixes(), 0};
   }
 
 private:
+  void cleanupLine(AnnotatedLine *Line) {
+    for (auto *Child : Line->Children) {
+      cleanupLine(Child);
+    }
+
+    if (Line->Affected) {
+      cleanupRight(Line->First, tok::comma, tok::comma);
+      cleanupRight(Line->First, TT_CtorInitializerColon, tok::comma);
+      cleanupRight(Line->First, tok::l_paren, tok::comma);
+      cleanupLeft(Line->First, tok::comma, tok::r_paren);
+      cleanupLeft(Line->First, TT_CtorInitializerComma, tok::l_brace);
+      cleanupLeft(Line->First, TT_CtorInitializerColon, tok::l_brace);
+      cleanupLeft(Line->First, TT_CtorInitializerColon, tok::equal);
+    }
+  }
+
   bool containsOnlyComments(const AnnotatedLine &Line) {
     for (FormatToken *Tok = Line.First; Tok != nullptr; Tok = Tok->Next) {
       if (Tok->isNot(tok::comment))
diff --git a/clang/unittests/Format/CleanupTest.cpp b/clang/unittests/Format/CleanupTest.cpp
index 0628c38..b0c81b5 100644
--- a/clang/unittests/Format/CleanupTest.cpp
+++ b/clang/unittests/Format/CleanupTest.cpp
@@ -183,10 +183,15 @@ TEST_F(CleanupTest, TrailingCommaInParens) {
   std::string Code = "int main() { f(,1,,2,3,f(1,2,),4,,);}";
   std::string Expected = "int main() { f(1,2,3,f(1,2),4);}";
   EXPECT_EQ(Expected, cleanupAroundOffsets({15, 18, 29, 33}, Code));
+
+  // Lambda contents are also checked for trailing commas.
+  Code = "int main() { [](){f(,1,,2,3,f(1,2,),4,,);}();}";
+  Expected = "int main() { [](){f(1,2,3,f(1,2),4);}();}";
+  EXPECT_EQ(Expected, cleanupAroundOffsets({20, 23, 34, 38}, Code));
 }
 
 TEST_F(CleanupTest, TrailingCommaInBraces) {
-  // Trainling comma is allowed in brace list.
+  // Trailing comma is allowed in brace list.
   // If there was trailing comma in the original code, then trailing comma is
   // preserved. In this example, element between the last two commas is deleted
   // causing the second-last comma to be redundant.
@@ -194,7 +199,7 @@ TEST_F(CleanupTest, TrailingCommaInBraces) {
   std::string Expected = "void f() { std::vector<int> v = {1,2,3,}; }";
   EXPECT_EQ(Expected, cleanupAroundOffsets({39}, Code));
 
-  // If there was no trailing comma in the original code, then trainling comma
+  // If there was no trailing comma in the original code, then trailing comma
   // introduced by replacements should be cleaned up. In this example, the
   // element after the last comma is deleted causing the last comma to be
   // redundant.
-- 
2.7.4