[clang-format] [PR42417] clang-format inserts a space after '->' for operator->() overloading

[MyDeveloperDay]

Summary

https://bugs.llvm.org/show_bug.cgi?id=42417

This revision removes the extra space between the opertor-> and the parens ()

class Bug {
    auto operator-> () -> int*;
    auto operator++(int) -> int;
};

[mitchell-stellar]

LGTM

clang/lib/Format/TokenAnnotator.cpp

if (Current.is(Keywords.kw_instanceof)) {
       // having multiple variable declarations.
       Contexts.back().FirstStartOfName = nullptr;
     } else if (Current.isOneOf(tok::kw_auto, tok::kw___auto_type)) {
       AutoFound = true;
     } else if (Current.is(tok::arrow) &&
                Style.Language == FormatStyle::LK_Java) {
       Current.Type = TT_LambdaArrow;
     } else if (Current.is(tok::arrow) && AutoFound && Line.MustBeDeclaration &&
-               Current.NestingLevel == 0) {
+               Current.NestingLevel == 0 &&
+               !Current.Previous->is(tok::kw_operator)) {
+      // not auto operator->() -> xxx;
       Current.Type = TT_TrailingReturnArrow;
       TrailingReturnFound = true;
     } else if (Current.is(tok::star) ||
                (Current.isOneOf(tok::amp, tok::ampamp) &&
                 (Current.NestingLevel != 0 || !Line.MightBeFunctionDecl ||
                  TrailingReturnFound))) {
       Current.Type = determineStarAmpUsage(Current,
                                            Contexts.back().CanBeExpression &&

clang/unittests/Format/FormatTest.cpp

EXPECT_EQ("const aaaa::bbbbbbb &\n"
             "}",
             format("const aaaa::bbbbbbb\n"
                    "&ccccccccc::operator++() { stuff(); }",
                    getLLVMStyleWithColumns(40)));
 }
 
 TEST_F(FormatTest, TrailingReturnType) {
   verifyFormat("auto foo() -> int;\n");
+  // correct trailing return type spacing
+  verifyFormat("auto operator->() -> int;\n");
+  verifyFormat("auto operator++(int) -> int;\n");
+
   verifyFormat("struct S {\n"
                "  auto bar() const -> int;\n"
                "};");
   verifyFormat("template <size_t Order, typename T>\n"
                "auto load_img(const std::string &filename)\n"
                "    -> alias::tensor<Order, T, mem::tag::cpu> {}");
   verifyFormat("auto SomeFunction(A aaaaaaaaaaaaaaaaaaaaa) const\n"
                "    -> decltype(f(aaaaaaaaaaaaaaaaaaaaa)) {}");