clang-format: Prefer formatting local lambdas like functions.

Before:
  auto my_lambda =
      [](const string &some_parameter) { return some_parameter.size(); };

After:
  auto my_lambda = [](const string &some_parameter) {
    return some_parameter.size();
  };

llvm-svn: 237235

2 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 6cf3f1d5230..777de9bf1e3 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1593,6 +1593,9 @@ unsigned TokenAnnotator::splitPenalty(const AnnotatedLine &Line,
   if (Right.is(tok::l_square)) {
     if (Style.Language == FormatStyle::LK_Proto)
       return 1;
+    // Slightly prefer formatting local lambda definitions like functions.
+    if (Right.is(TT_LambdaLSquare) && Left.is(tok::equal))
+      return 50;
     if (!Right.isOneOf(TT_ObjCMethodExpr, TT_LambdaLSquare))
       return 500;
   }
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 371fa0f3d22..ecd78b24d09 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -9967,6 +9967,9 @@ TEST_F(FormatTest, FormatsLambdas) {
                "    : Field([] { // comment\n"
                "        int i;\n"
                "      }) {}");
+  verifyFormat("auto my_lambda = [](const string &some_parameter) {\n"
+               "  return some_parameter.size();\n"
+               "};");
 
   // Lambdas with return types.
   verifyFormat("int c = []() -> int { return 2; }();\n");