112 lines · cpp
1//===- unittests/Rewrite/RewriteBufferTest.cpp - RewriteBuffer tests ------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/ADT/RewriteBuffer.h"10#include "gtest/gtest.h"11 12using namespace llvm;13 14namespace {15 16#define EXPECT_OUTPUT(Buf, Output) EXPECT_EQ(Output, writeOutput(Buf))17 18static std::string writeOutput(const RewriteBuffer &Buf) {19 std::string Result;20 raw_string_ostream OS(Result);21 Buf.write(OS);22 return Result;23}24 25static void tagRange(unsigned Offset, unsigned Len, StringRef tagName,26 RewriteBuffer &Buf) {27 std::string BeginTag;28 raw_string_ostream(BeginTag) << '<' << tagName << '>';29 std::string EndTag;30 raw_string_ostream(EndTag) << "</" << tagName << '>';31 32 Buf.InsertTextAfter(Offset, BeginTag);33 Buf.InsertTextBefore(Offset + Len, EndTag);34}35 36TEST(RewriteBuffer, TagRanges) {37 StringRef Input = "hello world";38 const char *Output = "<outer><inner>hello</inner></outer> ";39 40 RewriteBuffer Buf;41 Buf.Initialize(Input);42 StringRef RemoveStr = "world";43 size_t Pos = Input.find(RemoveStr);44 Buf.RemoveText(Pos, RemoveStr.size());45 46 StringRef TagStr = "hello";47 Pos = Input.find(TagStr);48 tagRange(Pos, TagStr.size(), "outer", Buf);49 tagRange(Pos, TagStr.size(), "inner", Buf);50 51 EXPECT_OUTPUT(Buf, Output);52}53 54TEST(RewriteBuffer, DISABLED_RemoveLineIfEmpty_XFAIL) {55 StringRef Input = "def\n"56 "ghi\n"57 "jkl\n";58 RewriteBuffer Buf;59 Buf.Initialize(Input);60 61 // Insert "abc\n" at the start.62 Buf.InsertText(0, "abc\n");63 EXPECT_OUTPUT(Buf, "abc\n"64 "def\n"65 "ghi\n"66 "jkl\n");67 68 // Remove "def\n".69 //70 // After the removal of "def", we have:71 //72 // "abc\n"73 // "\n"74 // "ghi\n"75 // "jkl\n"76 //77 // Because removeLineIfEmpty=true, RemoveText has to remove the "\n" left on78 // the line. This happens correctly for the rewrite buffer itself, so the79 // next check below passes.80 //81 // However, RemoveText's implementation incorrectly records the delta for82 // removing the "\n" using the rewrite buffer offset, 4, where it was83 // supposed to use the original input offset, 3. Interpreted as an original84 // input offset, 4 points to "g" not to "\n". Thus, any future modifications85 // at the original input's "g" will incorrectly see "g" as having become an86 // empty string and so will map to the next character, "h", in the rewrite87 // buffer.88 StringRef RemoveStr0 = "def";89 Buf.RemoveText(Input.find(RemoveStr0), RemoveStr0.size(),90 /*removeLineIfEmpty*/ true);91 EXPECT_OUTPUT(Buf, "abc\n"92 "ghi\n"93 "jkl\n");94 95 // Try to remove "ghi\n".96 //97 // As discussed above, the original input offset for "ghi\n" incorrectly98 // maps to the rewrite buffer offset for "hi\nj", so we end up with:99 //100 // "abc\n"101 // "gkl\n"102 //103 // To show that removeLineIfEmpty=true is the culprit, change true to false104 // and append a newline to RemoveStr0 above. The test then passes.105 StringRef RemoveStr1 = "ghi\n";106 Buf.RemoveText(Input.find(RemoveStr1), RemoveStr1.size());107 EXPECT_OUTPUT(Buf, "abc\n"108 "jkl\n");109}110 111} // anonymous namespace112