[clang-format] Do not break before long string literals in protos

Summary:
This patch is a follow-up to r323319 (which disables string literal breaking for
text protos) and it disables breaking before long string literals.

For example this:
```
keyyyyy: "long string literal"
```
used to get broken into:
```
keyyyyy:
    "long string literal"
```

While at it, I also enabled it for LK_Proto and fixed a bug in the mustBreak code.

Reviewers: djasper, sammccall

Reviewed By: djasper

Subscribers: klimek, cfe-commits

Differential Revision: https://reviews.llvm.org/D42957

llvm-svn: 324591

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/unittests/Format/FormatTestProto.cpp b/clang/unittests/Format/FormatTestProto.cpp
index 3889bc67766..d667ec2b3e9 100644
--- a/clang/unittests/Format/FormatTestProto.cpp
+++ b/clang/unittests/Format/FormatTestProto.cpp
@@ -412,5 +412,14 @@ TEST_F(FormatTestProto, FormatsImports) {
                "}");
 }
 
+TEST_F(FormatTestProto, KeepsLongStringLiteralsOnSameLine) {
+  verifyFormat(
+      "option (MyProto.options) = {\n"
+      "  foo: {\n"
+      "    text: \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaasaaaaaaaa\"\n"
+      "  }\n"
+      "}");
+}
+
 } // end namespace tooling
 } // end namespace clang