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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/ADT/RewriteBuffer.h" 10 #include "gtest/gtest.h" 11 12 using namespace llvm; 13 14 namespace { 15 16 #define EXPECT_OUTPUT(Buf, Output) EXPECT_EQ(Output, writeOutput(Buf)) 17 18 static 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 25 static 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 36 TEST(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 54 TEST(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 on 78 // the line. This happens correctly for the rewrite buffer itself, so the 79 // next check below passes. 80 // 81 // However, RemoveText's implementation incorrectly records the delta for 82 // removing the "\n" using the rewrite buffer offset, 4, where it was 83 // supposed to use the original input offset, 3. Interpreted as an original 84 // input offset, 4 points to "g" not to "\n". Thus, any future modifications 85 // at the original input's "g" will incorrectly see "g" as having become an 86 // empty string and so will map to the next character, "h", in the rewrite 87 // 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" incorrectly 98 // 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 false 104 // 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 namespace 112