clang-format: [JS] supports casts to types starting with punctuation ("{[(").

[mprobst]

Summary

Before:

x as{x: number}

After:

x as {x: number}

[ygao]

lib/Format/FormatTokenLexer.cpp

245 ↗

(On Diff #68817)

What happens if the '${' is immediately after a backslash (the if statement above), should the '${' get escaped?

[mprobst]

• drop accidentally included template string patch from this diff.

[mprobst]

lib/Format/FormatTokenLexer.cpp

245 ↗

(On Diff #68817)

Sorry, I accidentally included this in the wrong diff – the template string thing is in D22431. I'll answer there.

[djasper]

Please add a "before" and "after" to the patch description before submitting. Otherwise looks good.

cfe/trunk/lib/Format/TokenAnnotator.cpp

if (Left.is(TT_JsFatArrow))
       return true;
     if (Right.is(tok::star) &&
         Left.isOneOf(Keywords.kw_function, Keywords.kw_yield))
       return false;
     if (Left.isOneOf(Keywords.kw_let, Keywords.kw_var, Keywords.kw_in,
                      Keywords.kw_of, tok::kw_const) &&
         (!Left.Previous || !Left.Previous->is(tok::period)))
       return true;
+    if (Left.is(Keywords.kw_as) &&
+        Right.isOneOf(tok::l_square, tok::l_brace, tok::l_paren))
+      return true;
     if (Left.is(tok::kw_default) && Left.Previous &&
         Left.Previous->is(tok::kw_export))
       return true;
     if (Left.is(Keywords.kw_is) && Right.is(tok::l_brace))
       return true;
     if (Right.isOneOf(TT_JsTypeColon, TT_JsTypeOptionalQuestion))
       return false;
     if (Left.is(TT_JsTypeOperator) || Right.is(TT_JsTypeOperator))

cfe/trunk/unittests/Format/FormatTestJS.cpp

TEST_F(FormatTestJS, CastSyntax) {
   verifyFormat("let x = (a + b) as\n"
                "    LongTypeIsLong;",
                getGoogleJSStyleWithColumns(20));
   verifyFormat("foo = <Bar[]>[\n"
                "  1,  //\n"
                "  2\n"
                "];");
   verifyFormat("var x = [{x: 1} as type];");
+  verifyFormat("x = x as [a, b];");
+  verifyFormat("x = x as {a: string};");
+  verifyFormat("x = x as (string);");
 }
 
 TEST_F(FormatTestJS, TypeArguments) {
   verifyFormat("class X<Y> {}");
   verifyFormat("new X<Y>();");
   verifyFormat("foo<Y>(a);");
   verifyFormat("var x: X<Y>[];");
   verifyFormat("class C extends D<E> implements F<G>, H<I> {}");