clang-format: [JS] keep triple slash directives intact.

[mprobst]

Summary

TypeScript uses triple slash directives of the form:

/// <reference path="..."/>

For various non-source instructions that should not be wrapped.

Reference:
https://www.typescriptlang.org/docs/handbook/triple-slash-directives.html

[djasper]

Looks good.

lib/Format/Format.cpp

if (Language == FormatStyle::LK_Java) {
     GoogleStyle.SpaceAfterCStyleCast = true;
     GoogleStyle.SpacesBeforeTrailingComments = 1;
   } else if (Language == FormatStyle::LK_JavaScript) {
     GoogleStyle.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
     GoogleStyle.AlignOperands = false;
     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Empty;
     GoogleStyle.AlwaysBreakBeforeMultilineStrings = false;
     GoogleStyle.BreakBeforeTernaryOperators = false;
-    // taze:, @tag followed by { for a lot of JSDoc tags, and @see, which is
-    // commonly followed by overlong URLs.
-    GoogleStyle.CommentPragmas = "(taze:|(@[A-Za-z_0-9-]+[ \\t]*{)|@see)";
+    // taze:, triple slash directives (`/// <...`), @tag followed by { for a lot
+    // of JSDoc tags, and @see, which is commonly followed by overlong URLs.
+    GoogleStyle.CommentPragmas =
+        "(taze:|^/[ \t]*<|(@[A-Za-z_0-9-]+[ \\t]*{)|@see)";
     GoogleStyle.MaxEmptyLinesToKeep = 3;
     GoogleStyle.NamespaceIndentation = FormatStyle::NI_All;
     GoogleStyle.SpacesInContainerLiterals = false;
     GoogleStyle.JavaScriptQuotes = FormatStyle::JSQS_Single;
     GoogleStyle.JavaScriptWrapImports = false;
   } else if (Language == FormatStyle::LK_Proto) {
     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_None;
     GoogleStyle.SpacesInContainerLiterals = false;

unittests/Format/FormatTestJS.cpp

verifyFormat("class Foo {\n"
                "  method(a = true ? 1 : 2) {}\n"
                "}");
 }
 
 TEST_F(FormatTestJS, ImportComments) {
   verifyFormat("import {x} from 'x';  // from some location",
                getGoogleJSStyleWithColumns(25));
   verifyFormat("// taze: x from 'location'", getGoogleJSStyleWithColumns(10));
+  verifyFormat("/// <reference path=\"some/location\" />", getGoogleJSStyleWithColumns(10));
 }
 
 TEST_F(FormatTestJS, Exponentiation) {
   verifyFormat("squared = x ** 2;");
   verifyFormat("squared **= 2;");
 }
 
 } // end namespace tooling
 } // end namespace clang