[clang-format] Stop breaking unbreakable strings in JS (#66168)

Dictionary literal keys and strings in TypeScript type declarations can
not be broken.

The problem was pointed out by @alexfh and @e-kud here:

https://reviews.llvm.org/D154093#4644512

1 files changed, 22 insertions, 0 deletions

diff --git a/clang/unittests/Format/FormatTestJS.cpp b/clang/unittests/Format/FormatTestJS.cpp
index bc4c7ff..30932656 100644
--- a/clang/unittests/Format/FormatTestJS.cpp
+++ b/clang/unittests/Format/FormatTestJS.cpp
@@ -1596,6 +1596,28 @@ TEST_F(FormatTestJS, StringLiteralConcatenation) {
                "var literal = `xxxxxx ${xxxxxxxxxxxxxxxxxxxxxx + "
                "xxxxxxxxxxxxxxxxxxxxxx} xxxxxx`;",
                getGoogleJSStyleWithColumns(14));
+
+  // Strings in a TypeScript type declaration can't be broken.
+  verifyFormat("type x =\n"
+               "    'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';",
+               getGoogleJSStyleWithColumns(20));
+  verifyFormat("/* type */ type x =\n"
+               "    'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';",
+               getGoogleJSStyleWithColumns(20));
+  // Dictionary keys can't be broken. Values can be broken.
+  verifyFormat("var w = {\n"
+               "  'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx':\n"
+               "      'xxxxxxxxxx' +\n"
+               "      'xxxxxxxxxx' +\n"
+               "      'xxxxxxxxxx' +\n"
+               "      'xxxxxxxxxx' +\n"
+               "      'xxx',\n"
+               "};",
+               "var w = {\n"
+               "  'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx':\n"
+               "      'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',\n"
+               "};",
+               getGoogleJSStyleWithColumns(20));
 }
 
 TEST_F(FormatTestJS, RegexLiteralClassification) {