1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
//===--- AvoidConstParamsInDecls.cpp - clang-tidy--------------------------===//
//
// 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 "AvoidConstParamsInDecls.h"
#include "../utils/LexerUtils.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/ASTMatchers/ASTMatchers.h"
#include "clang/Lex/Lexer.h"
using namespace clang::ast_matchers;
namespace clang::tidy::readability {
namespace {
SourceRange getTypeRange(const ParmVarDecl &Param) {
return {Param.getBeginLoc(), Param.getLocation().getLocWithOffset(-1)};
}
// Finds the location of the qualifying `const` token in the `ParmValDecl`'s
// return type. Returns `std::nullopt` when the parm type is not
// `const`-qualified like when the type is an alias or a macro.
static std::optional<Token>
findConstToRemove(const ParmVarDecl &Param,
const MatchFinder::MatchResult &Result) {
CharSourceRange FileRange = Lexer::makeFileCharRange(
CharSourceRange::getTokenRange(getTypeRange(Param)),
*Result.SourceManager, Result.Context->getLangOpts());
if (FileRange.isInvalid())
return std::nullopt;
return tidy::utils::lexer::getQualifyingToken(
tok::kw_const, FileRange, *Result.Context, *Result.SourceManager);
}
} // namespace
void AvoidConstParamsInDecls::storeOptions(ClangTidyOptions::OptionMap &Opts) {
Options.store(Opts, "IgnoreMacros", IgnoreMacros);
}
void AvoidConstParamsInDecls::registerMatchers(MatchFinder *Finder) {
const auto ConstParamDecl =
parmVarDecl(hasType(qualType(isConstQualified()))).bind("param");
Finder->addMatcher(functionDecl(unless(isDefinition()),
has(typeLoc(forEach(ConstParamDecl))))
.bind("func"),
this);
}
void AvoidConstParamsInDecls::check(const MatchFinder::MatchResult &Result) {
const auto *Func = Result.Nodes.getNodeAs<FunctionDecl>("func");
const auto *Param = Result.Nodes.getNodeAs<ParmVarDecl>("param");
if (!Param->getType().isLocalConstQualified())
return;
if (IgnoreMacros &&
(Param->getBeginLoc().isMacroID() || Param->getEndLoc().isMacroID())) {
// Suppress the check if macros are involved.
return;
}
const auto Tok = findConstToRemove(*Param, Result);
const auto ConstLocation = Tok ? Tok->getLocation() : Param->getBeginLoc();
auto Diag = diag(ConstLocation,
"parameter %0 is const-qualified in the function "
"declaration; const-qualification of parameters only has an "
"effect in function definitions");
if (Param->getName().empty()) {
for (unsigned int I = 0; I < Func->getNumParams(); ++I) {
if (Param == Func->getParamDecl(I)) {
Diag << (I + 1);
break;
}
}
} else {
Diag << Param;
}
if (Param->getBeginLoc().isMacroID() != Param->getEndLoc().isMacroID()) {
// Do not offer a suggestion if the part of the variable declaration comes
// from a macro.
return;
}
if (!Tok)
return;
Diag << FixItHint::CreateRemoval(
CharSourceRange::getTokenRange(Tok->getLocation(), Tok->getLocation()));
}
} // namespace clang::tidy::readability
|
