llvm-project/clang/unittests/Rewrite/RewriteBufferTest.cpp

114 lines
3.4 KiB
C++

//===- unittests/Rewrite/RewriteBufferTest.cpp - RewriteBuffer tests ------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "clang/Rewrite/Core/RewriteBuffer.h"
#include "gtest/gtest.h"
using namespace llvm;
using namespace clang;
namespace {
#define EXPECT_OUTPUT(Buf, Output) EXPECT_EQ(Output, writeOutput(Buf))
static std::string writeOutput(const RewriteBuffer &Buf) {
std::string Result;
raw_string_ostream OS(Result);
Buf.write(OS);
OS.flush();
return Result;
}
static void tagRange(unsigned Offset, unsigned Len, StringRef tagName,
RewriteBuffer &Buf) {
std::string BeginTag;
raw_string_ostream(BeginTag) << '<' << tagName << '>';
std::string EndTag;
raw_string_ostream(EndTag) << "</" << tagName << '>';
Buf.InsertTextAfter(Offset, BeginTag);
Buf.InsertTextBefore(Offset+Len, EndTag);
}
TEST(RewriteBuffer, TagRanges) {
StringRef Input = "hello world";
const char *Output = "<outer><inner>hello</inner></outer> ";
RewriteBuffer Buf;
Buf.Initialize(Input);
StringRef RemoveStr = "world";
size_t Pos = Input.find(RemoveStr);
Buf.RemoveText(Pos, RemoveStr.size());
StringRef TagStr = "hello";
Pos = Input.find(TagStr);
tagRange(Pos, TagStr.size(), "outer", Buf);
tagRange(Pos, TagStr.size(), "inner", Buf);
EXPECT_OUTPUT(Buf, Output);
}
TEST(RewriteBuffer, DISABLED_RemoveLineIfEmpty_XFAIL) {
StringRef Input = "def\n"
"ghi\n"
"jkl\n";
RewriteBuffer Buf;
Buf.Initialize(Input);
// Insert "abc\n" at the start.
Buf.InsertText(0, "abc\n");
EXPECT_OUTPUT(Buf, "abc\n"
"def\n"
"ghi\n"
"jkl\n");
// Remove "def\n".
//
// After the removal of "def", we have:
//
// "abc\n"
// "\n"
// "ghi\n"
// "jkl\n"
//
// Because removeLineIfEmpty=true, RemoveText has to remove the "\n" left on
// the line. This happens correctly for the rewrite buffer itself, so the
// next check below passes.
//
// However, RemoveText's implementation incorrectly records the delta for
// removing the "\n" using the rewrite buffer offset, 4, where it was
// supposed to use the original input offset, 3. Interpreted as an original
// input offset, 4 points to "g" not to "\n". Thus, any future modifications
// at the original input's "g" will incorrectly see "g" as having become an
// empty string and so will map to the next character, "h", in the rewrite
// buffer.
StringRef RemoveStr0 = "def";
Buf.RemoveText(Input.find(RemoveStr0), RemoveStr0.size(),
/*removeLineIfEmpty*/ true);
EXPECT_OUTPUT(Buf, "abc\n"
"ghi\n"
"jkl\n");
// Try to remove "ghi\n".
//
// As discussed above, the original input offset for "ghi\n" incorrectly
// maps to the rewrite buffer offset for "hi\nj", so we end up with:
//
// "abc\n"
// "gkl\n"
//
// To show that removeLineIfEmpty=true is the culprit, change true to false
// and append a newline to RemoveStr0 above. The test then passes.
StringRef RemoveStr1 = "ghi\n";
Buf.RemoveText(Input.find(RemoveStr1), RemoveStr1.size());
EXPECT_OUTPUT(Buf, "abc\n"
"jkl\n");
}
} // anonymous namespace