[clang-format] fix crash in NamespaceEndCommentsFixer (PR32438)

[mgehre]

Summary

The new test case was crashing before. Now it passes
as expected.

[krasimir]

Looks good! I just have two nits.

lib/Format/NamespaceEndCommentsFixer.cpp

139

I'd instead just add a guard check at old line 136:

if (!NamespaceTok || NamespaceTok->isNot(tok::kw_namespace))
  continue;

unittests/Format/NamespaceEndCommentsFixerTest.cpp

586

I'd make the test name a bit descriptive; something like:
HandlesInlineAtEndOfLine_PR32438

[mgehre]

Updated for comments

[krasimir]

Great!

lib/Format/NamespaceEndCommentsFixer.cpp

if (!AnnotatedLines[I]->Affected || AnnotatedLines[I]->InPPDirective ||
       continue;
     const AnnotatedLine *EndLine = AnnotatedLines[I];
     size_t StartLineIndex = EndLine->MatchingOpeningBlockLineIndex;
     if (StartLineIndex == UnwrappedLine::kInvalidIndex)
       continue;
     assert(StartLineIndex < E);
     const FormatToken *NamespaceTok = AnnotatedLines[StartLineIndex]->First;
     // Detect "(inline)? namespace" in the beginning of a line.
-    if (NamespaceTok->is(tok::kw_inline))
+    if (NamespaceTok->is(tok::kw_inline)) {
       NamespaceTok = NamespaceTok->getNextNonComment();
+      if (!NamespaceTok)
+        continue;
+    }
     if (NamespaceTok->isNot(tok::kw_namespace))
       continue;
     FormatToken *RBraceTok = EndLine->First;
     if (RBraceTok->Finalized)
       continue;
     RBraceTok->Finalized = true;
     const FormatToken *EndCommentPrevTok = RBraceTok;
     // Namespaces often end with '};'. In that case, attach namespace end
     // comments to the semicolon tokens.

unittests/Format/NamespaceEndCommentsFixerTest.cpp

EXPECT_EQ("namespace {\n"
             "  int i;\n"
             "} // namespace\n"
             "}",
             fixNamespaceEndComments("namespace {\n"
                                     "  int i;\n"
                                     "} // namespace\n"
                                     "}"));
 }
+
+TEST_F(NamespaceEndCommentsFixerTest, PR32438) {
+  EXPECT_EQ("template <int> struct a {};\n"
+            "struct a<bool{}> b() {\n"
+            "}\n"
+            "#define c inline\n"
+            "void d() {\n"
+            "}\n",
+            fixNamespaceEndComments("template <int> struct a {};\n"
+                                    "struct a<bool{}> b() {\n"
+                                    "}\n"
+                                    "#define c inline\n"
+                                    "void d() {\n"
+                                    "}\n"));
+}
 } // end namespace
 } // end namespace format
 } // end namespace clang