Skip over AnnotatedLines with >50 levels of nesting; don't format them.
Reasoning:
- ExpressionParser uses a lot of stack for these, bad in some environments.
- Our formatting algorithm is N^3 and gets really slow.
- The resulting formatting is unlikely to be any good.
- This is probably generated code we're formatting by accident.
We treat these as unparseable, and signal incomplete formatting. 50 is
an arbitrary number, I've only seen real problems from ~150 levels.
Patch by Sam McCall. Thank you.
llvm-svn: 285570
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index ee08121..b95a29f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7179,6 +7179,30 @@
verifyFormat("operator");
}
+TEST_F(FormatTest, SkipsDeeplyNestedLines) {
+ // This code would be painfully slow to format if we didn't skip it.
+ std::string Code("A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(\n" // 20x
+ "A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(\n"
+ "A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(\n"
+ "A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(\n"
+ "A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(A(\n"
+ "A(1, 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n" // 10x
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1)\n"
+ ", 1), 1), 1), 1), 1), 1), 1), 1), 1), 1);\n");
+ // Deeply nested part is untouched, rest is formatted.
+ EXPECT_EQ(std::string("int i;\n") + Code + "int j;\n",
+ format(std::string("int i;\n") + Code + "int j;\n",
+ getLLVMStyle(), IC_ExpectIncomplete));
+}
+
//===----------------------------------------------------------------------===//
// Objective-C tests.
//===----------------------------------------------------------------------===//