[clang-format] Fix crashes due to missing l_paren

Fixes #54384.

Differential Revision: https://reviews.llvm.org/D121682

Author: owenca

clang/lib/Format/TokenAnnotator.cpp

@@ -1023,6 +1023,8 @@ class AnnotatingParser {
       if (Style.isCpp() && CurrentToken && CurrentToken->is(tok::kw_co_await))
         next();
       Contexts.back().ColonIsForRangeExpr = true;
+      if (!CurrentToken || CurrentToken->isNot(tok::l_paren))
+        return false;
       next();
       if (!parseParens())
         return false;

clang/unittests/Format/FormatTest.cpp

@@ -12113,6 +12113,7 @@ TEST_F(FormatTest, IncorrectCodeMissingParens) {
   verifyFormat("if {\n  foo;\n  foo();\n}");
   verifyFormat("switch {\n  foo;\n  foo();\n}");
   verifyIncompleteFormat("for {\n  foo;\n  foo();\n}");
+  verifyIncompleteFormat("ERROR: for target;");
   verifyFormat("while {\n  foo;\n  foo();\n}");
   verifyFormat("do {\n  foo;\n  foo();\n} while;");
 }