From c29f83b79e748e36f9af06adde8953e9c009b35c Mon Sep 17 00:00:00 2001
From: Nico Weber <nicolasweber@gmx.de>
Date: Tue, 23 Jan 2018 16:30:56 +0000
Subject: [PATCH] clang-format: Support formatting Java 8 interface default
 methods.

llvm-svn: 323218
---
 clang/lib/Format/UnwrappedLineParser.cpp  | 21 ++++++++++++++++++---
 clang/unittests/Format/FormatTestJava.cpp |  1 +
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index b8608dc..3fac75d 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -333,7 +333,18 @@ void UnwrappedLineParser::parseLevel(bool HasOpeningBrace) {
       nextToken();
       addUnwrappedLine();
       break;
-    case tok::kw_default:
+    case tok::kw_default: {
+      unsigned StoredPosition = Tokens->getPosition();
+      FormatToken *Next = Tokens->getNextToken();
+      FormatTok = Tokens->setPosition(StoredPosition);
+      if (Next && Next->isNot(tok::colon)) {
+        // default not followed by ':' is not a case label; treat it like
+        // an identifier.
+        parseStructuralElement();
+        break;
+      }
+      // Else, if it is 'default:', fall through to the case handling.
+    }
     case tok::kw_case:
       if (Style.Language == FormatStyle::LK_JavaScript &&
           Line->MustBeDeclaration) {
@@ -1032,8 +1043,12 @@ void UnwrappedLineParser::parseStructuralElement() {
       // 'default: string' field declaration.
       break;
     nextToken();
-    parseLabel();
-    return;
+    if (FormatTok->is(tok::colon)) {
+      parseLabel();
+      return;
+    }
+    // e.g. "default void f() {}" in a Java interface.
+    break;
   case tok::kw_case:
     if (Style.Language == FormatStyle::LK_JavaScript && Line->MustBeDeclaration)
       // 'case: string' field declaration.
diff --git a/clang/unittests/Format/FormatTestJava.cpp b/clang/unittests/Format/FormatTestJava.cpp
index 2f376f7..1d471b7 100644
--- a/clang/unittests/Format/FormatTestJava.cpp
+++ b/clang/unittests/Format/FormatTestJava.cpp
@@ -144,6 +144,7 @@ TEST_F(FormatTestJava, ClassDeclarations) {
   verifyFormat("public interface SomeInterface {\n"
                "  void doStuff(int theStuff);\n"
                "  void doMoreStuff(int moreStuff);\n"
+               "  default void doStuffWithDefault() {}\n"
                "}");
   verifyFormat("@interface SomeInterface {\n"
                "  void doStuff(int theStuff);\n"
-- 
2.7.4