clang-format: [JS] do not insert semicolons after wrapped annotations.

[djasper]

lib/Format/UnwrappedLineParser.cpp

708

How about:

• Moving this down a bit
• Checking this only if PreviousMustBeValue
• return directly

Like this, it is a bit hard to understand all the combinations of what's going on.

[mprobst]

• simplify conditions

[mprobst]

lib/Format/UnwrappedLineParser.cpp

708

Good point. I was under the impression initially that I had to check the token before getting the next here.

[djasper]

Looks good.

unittests/Format/FormatTestJS.cpp

689

Are there any other valid use cases of "@" in JS? If so, should we add a test for at least one of those?

[mprobst]

unittests/Format/FormatTestJS.cpp

689

@ can only be used for annotations. Those can appear on classes, fields, methods, and parameters. I'll send another review to add tests for those, they are currently formatted properly (inheriting the Java support for them).

lib/Format/UnwrappedLineParser.cpp

 // readTokenWithJavaScriptASI reads the next token and terminates the current
 // line if JavaScript Automatic Semicolon Insertion must
 // happen between the current token and the next token.
 //
 // This method is conservative - it cannot cover all edge cases of JavaScript,
 // but only aims to correctly handle certain well known cases. It *must not*
 // return true in speculative cases.
 void UnwrappedLineParser::readTokenWithJavaScriptASI() {
+  bool PreviousIsAnnotation = false;
+  if (Line && Line->Tokens.size() > 1) {
+    // If the token before the previous one is an '@', the previous token is an
+    // annotation and can precede another identifier/value.
+    const FormatToken *PrePrevious = std::next(Line->Tokens.rend(), 2)->Tok;
+    PreviousIsAnnotation = PrePrevious->is(tok::at);
+  }
   FormatToken *Previous = FormatTok;
   readToken();
   FormatToken *Next = FormatTok;
 
   bool IsOnSameLine =
       CommentsBeforeNextToken.empty()
           ? Next->NewlinesBefore == 0
           : CommentsBeforeNextToken.front()->NewlinesBefore == 0;
   if (IsOnSameLine)
     return;
 
-  bool PreviousMustBeValue = mustBeJSIdentOrValue(Keywords, Previous);
+  bool PreviousMustBeValue =
+      !PreviousIsAnnotation && mustBeJSIdentOrValue(Keywords, Previous);
   if (Next->is(tok::exclaim) && PreviousMustBeValue)
     addUnwrappedLine();
   bool NextMustBeValue = mustBeJSIdentOrValue(Keywords, Next);
   if (NextMustBeValue && (PreviousMustBeValue ||
                           Previous->isOneOf(tok::r_square, tok::r_paren,
                                             tok::plusplus, tok::minusminus)))
     addUnwrappedLine();
   if (PreviousMustBeValue && isJSDeclOrStmt(Keywords, Next))

unittests/Format/FormatTestJS.cpp

verifyFormat("a\n"
                "class X {}",
                " a\n"
                " class X {}");
   verifyFormat("var a", "var\n"
                         "a");
   verifyFormat("x instanceof String", "x\n"
                                       "instanceof\n"
                                       "String");
+  verifyFormat("function f(@Foo bar) {}", "function f(@Foo\n"
+                                          "  bar) {}");
 }
 
 TEST_F(FormatTestJS, ClosureStyleCasts) {
   verifyFormat("var x = /** @type {foo} */ (bar);");
 }
 
 TEST_F(FormatTestJS, TryCatch) {
   verifyFormat("try {\n"