clang-format: Do not binpack initialization lists

Summary:
This patch tries to avoid binpacking when initializing lists/arrays, to allow things like:

  static int types[] = {
      registerType1(),
      registerType2(),
      registerType3(),
  };
  std::map<int, std::string> x = {
      { 0, "foo fjakfjaklf kljj" },
      { 1, "bar fjakfjaklf kljj" },
      { 2, "stuff fjakfjaklf kljj" },
  };

This is similar to how dictionnaries are formatted, and actually corresponds to the same conditions: when initializing a container (and not just 'calling' a constructor).

Such formatting involves 2 things:
* Line breaks around the content of the block. This can be forced by adding a comma or comment after the last element
* Elements should not be binpacked

This patch considers the block is an initializer list if it either ends with a comma, or follows an assignment, which seems to provide a sensible approximation.

Reviewers: krasimir, djasper

Reviewed By: djasper

Subscribers: malcolm.parsons, klimek, cfe-commits

Differential Revision: https://reviews.llvm.org/D34238

llvm-svn: 306868

1 files changed, 4 insertions, 1 deletions

diff --git a/clang/unittests/Format/FormatTestJava.cpp b/clang/unittests/Format/FormatTestJava.cpp
index 6e685f6..b9cfaff 100644
--- a/clang/unittests/Format/FormatTestJava.cpp
+++ b/clang/unittests/Format/FormatTestJava.cpp
@@ -237,7 +237,10 @@ TEST_F(FormatTestJava, EnumDeclarations) {
 TEST_F(FormatTestJava, ArrayInitializers) {
   verifyFormat("new int[] {1, 2, 3, 4};");
   verifyFormat("new int[] {\n"
-               "    1, 2, 3, 4,\n"
+               "    1,\n"
+               "    2,\n"
+               "    3,\n"
+               "    4,\n"
                "};");
 
   FormatStyle Style = getStyleWithColumns(65);