1//===--- SourceCode.cpp - Source code manipulation routines -----*- C++ -*-===//
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//  This file provides functions that simplify extraction of source code.
10//
11//===----------------------------------------------------------------------===//
12#include "clang/Tooling/Transformer/SourceCode.h"
13#include "clang/Lex/Lexer.h"
14
15using namespace clang;
16
17StringRef clang::tooling::getText(CharSourceRange Range,
18                                  const ASTContext &Context) {
19  return Lexer::getSourceText(Range, Context.getSourceManager(),
20                              Context.getLangOpts());
21}
22
23CharSourceRange clang::tooling::maybeExtendRange(CharSourceRange Range,
24                                                 tok::TokenKind Next,
25                                                 ASTContext &Context) {
26  Optional<Token> Tok = Lexer::findNextToken(
27      Range.getEnd(), Context.getSourceManager(), Context.getLangOpts());
28  if (!Tok || !Tok->is(Next))
29    return Range;
30  return CharSourceRange::getTokenRange(Range.getBegin(), Tok->getLocation());
31}
32
33llvm::Optional<CharSourceRange>
34clang::tooling::getRangeForEdit(const CharSourceRange &EditRange,
35                                const SourceManager &SM,
36                                const LangOptions &LangOpts) {
37  // FIXME: makeFileCharRange() has the disadvantage of stripping off "identity"
38  // macros. For example, if we're looking to rewrite the int literal 3 to 6,
39  // and we have the following definition:
40  //    #define DO_NOTHING(x) x
41  // then
42  //    foo(DO_NOTHING(3))
43  // will be rewritten to
44  //    foo(6)
45  // rather than the arguably better
46  //    foo(DO_NOTHING(6))
47  // Decide whether the current behavior is desirable and modify if not.
48  CharSourceRange Range = Lexer::makeFileCharRange(EditRange, SM, LangOpts);
49  if (Range.isInvalid())
50    return None;
51
52  if (Range.getBegin().isMacroID() || Range.getEnd().isMacroID())
53    return None;
54  if (SM.isInSystemHeader(Range.getBegin()) ||
55      SM.isInSystemHeader(Range.getEnd()))
56    return None;
57
58  std::pair<FileID, unsigned> BeginInfo = SM.getDecomposedLoc(Range.getBegin());
59  std::pair<FileID, unsigned> EndInfo = SM.getDecomposedLoc(Range.getEnd());
60  if (BeginInfo.first != EndInfo.first ||
61      BeginInfo.second > EndInfo.second)
62    return None;
63
64  return Range;
65}
66