[clang-format] Fix SpacesInSquareBrackets for Lambdas with Initial "&…

…ref" Parameter

Summary:
This fixes an edge case in the `SpacesInSquareBrackets` option where an initial `&ref` lambda parameter is not padded with an initial space.

`int foo = [&bar ]() {}` is fixed to give `int foo = [ &bar ]() {}`

Reviewers: MyDeveloperDay, klimek, sammccall

Reviewed by: MyDeveloperDay

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D69649

clang/lib/Format/TokenAnnotator.cpp

@@ -2567,7 +2567,7 @@ bool TokenAnnotator::spaceRequiredBetween(const AnnotatedLine &Line,
     return Left.Tok.isLiteral() || (Left.is(tok::identifier) && Left.Previous &&
                                     Left.Previous->is(tok::kw_case));
   if (Left.is(tok::l_square) && Right.is(tok::amp))
-    return false;
+    return Style.SpacesInSquareBrackets;
   if (Right.is(TT_PointerOrReference)) {
     if (Left.is(tok::r_paren) && Line.MightBeFunctionDecl) {
       if (!Left.MatchingParen)

clang/unittests/Format/FormatTest.cpp

@@ -10572,6 +10572,10 @@ TEST_F(FormatTest, ConfigurableSpacesInSquareBrackets) {
   // Lambdas.
   verifyFormat("int c = []() -> int { return 2; }();\n", Spaces);
   verifyFormat("return [ i, args... ] {};", Spaces);
+  verifyFormat("int foo = [ &bar ]() {};", Spaces);
+  verifyFormat("int foo = [ = ]() {};", Spaces);
+  verifyFormat("int foo = [ =, &bar ]() {};", Spaces);
+  verifyFormat("int foo = [ &bar, = ]() {};", Spaces);
 }
 
 TEST_F(FormatTest, ConfigurableSpaceBeforeAssignmentOperators) {