clang-format: [JS] Do not break before 'as'.

[mprobst]

Summary

'as' is a pseudo operator, so automatic semicolon insertion kicks in and the
code fails to part.

[djasper]

Looks good.

lib/Format/TokenAnnotator.cpp

if (Style.Language == FormatStyle::LK_Java) {
     if (Left.is(TT_JsTypeColon))
       return true;
     if (Right.NestingLevel == 0 && Right.is(Keywords.kw_is))
       return false;
     if (Left.is(Keywords.kw_in))
       return Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None;
     if (Right.is(Keywords.kw_in))
       return Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None;
+    if (Right.is(Keywords.kw_as))
+      return false; // must not break before as in 'x as type' casts
   }
 
   if (Left.is(tok::at))
     return false;
   if (Left.Tok.getObjCKeywordID() == tok::objc_interface)
     return false;
   if (Left.isOneOf(TT_JavaAnnotation, TT_LeadingJavaAnnotation))
     return !Right.is(tok::l_paren);

unittests/Format/FormatTestJS.cpp

TEST_F(FormatTestJS, Modules) {
   verifyFormat("export {SomeVeryLongExport as X, "
                "SomeOtherVeryLongExport as Y} from 'some/module.js';");
   // export without 'from' is wrapped.
   verifyFormat("export let someRatherLongVariableName =\n"
                "    someSurprisinglyLongVariable + someOtherRatherLongVar;");
   // ... but not if from is just an identifier.
   verifyFormat("export {\n"
                "  from as from,\n"
-               "  someSurprisinglyLongVariable\n"
-               "      as from\n"
+               "  someSurprisinglyLongVariable as\n"
+               "      from\n"
                "};",
                getGoogleJSStyleWithColumns(20));
   verifyFormat("export class C {\n"
                "  x: number;\n"
                "  y: string;\n"
                "}");
   verifyFormat("export class X { y: number; }");
   verifyFormat("export abstract class X { y: number; }");
verifyFormat("var x = ` \\` a`;\n"
                "var y;",
                "var x = ` \\` a`;\n"
                "var y;");
 }
 
 TEST_F(FormatTestJS, CastSyntax) {
   verifyFormat("var x = <type>foo;");
   verifyFormat("var x = foo as type;");
+  verifyFormat("let x = (a + b) as\n"
+               "    LongTypeIsLong;",
+               getGoogleJSStyleWithColumns(20));
   verifyFormat("foo = <Bar[]>[\n"
                "  1,  //\n"
                "  2\n"
                "];");
 }
 
 TEST_F(FormatTestJS, TypeArguments) {
   verifyFormat("class X<Y> {}");