clang-tools 20.0.0git
NonZeroEnumToBoolConversionCheck.cpp
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1//===--- NonZeroEnumToBoolConversionCheck.cpp - clang-tidy ----------------===//
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
10#include "../utils/Matchers.h"
11#include "../utils/OptionsUtils.h"
12#include "clang/AST/ASTContext.h"
13#include "clang/ASTMatchers/ASTMatchFinder.h"
14#include <algorithm>
15
16using namespace clang::ast_matchers;
17
18namespace clang::tidy::bugprone {
19
20namespace {
21
22AST_MATCHER(EnumDecl, isCompleteAndHasNoZeroValue) {
23 const EnumDecl *Definition = Node.getDefinition();
24 return Definition && Node.isComplete() &&
25 std::none_of(Definition->enumerator_begin(),
26 Definition->enumerator_end(),
27 [](const EnumConstantDecl *Value) {
28 return Value->getInitVal().isZero();
29 });
30}
31
32} // namespace
33
35 StringRef Name, ClangTidyContext *Context)
36 : ClangTidyCheck(Name, Context),
37 EnumIgnoreList(
38 utils::options::parseStringList(Options.get("EnumIgnoreList", ""))) {}
39
42 Options.store(Opts, "EnumIgnoreList",
44}
45
47 const LangOptions &LangOpts) const {
48 return LangOpts.CPlusPlus;
49}
50
52 // Excluding bitwise operators (binary and overload) to avoid false-positives
53 // in code like this 'if (e & SUCCESS) {'.
54 auto ExcludedOperators = binaryOperation(hasAnyOperatorName(
55 "|", "&", "^", "<<", ">>", "~", "|=", "&=", "^=", "<<=", ">>="));
56
57 Finder->addMatcher(
58 castExpr(hasCastKind(CK_IntegralToBoolean),
59 unless(isExpansionInSystemHeader()), hasType(booleanType()),
60 hasSourceExpression(
61 expr(hasType(qualType(hasCanonicalType(hasDeclaration(
62 enumDecl(isCompleteAndHasNoZeroValue(),
64 EnumIgnoreList)))
65 .bind("enum"))))),
66 unless(declRefExpr(to(enumConstantDecl()))),
67 unless(ignoringParenImpCasts(ExcludedOperators)))),
68 unless(hasAncestor(staticAssertDecl())))
69 .bind("cast"),
70 this);
71}
72
74 const MatchFinder::MatchResult &Result) {
75 const auto *Cast = Result.Nodes.getNodeAs<CastExpr>("cast");
76 const auto *Enum = Result.Nodes.getNodeAs<EnumDecl>("enum");
77
78 diag(Cast->getExprLoc(), "conversion of %0 into 'bool' will always return "
79 "'true', enum doesn't have a zero-value enumerator")
80 << Enum;
81 diag(Enum->getLocation(), "enum is defined here", DiagnosticIDs::Note);
82}
83
84} // namespace clang::tidy::bugprone
llvm::SmallString< 256U > Name
::clang::DynTypedNode Node
void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName, StringRef Value) const
Stores an option with the check-local name LocalName with string value Value to Options.
Base class for all clang-tidy checks.
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check's name.
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
bool isLanguageVersionSupported(const LangOptions &LangOpts) const override
Override this to disable registering matchers and PP callbacks if an invalid language version is bein...
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
NonZeroEnumToBoolConversionCheck(StringRef Name, ClangTidyContext *Context)
AST_MATCHER(clang::VarDecl, hasConstantDeclaration)
inline ::clang::ast_matchers::internal::Matcher< NamedDecl > matchesAnyListedName(llvm::ArrayRef< StringRef > NameList)
std::string serializeStringList(ArrayRef< StringRef > Strings)
Serialize a sequence of names that can be parsed by parseStringList.
llvm::StringMap< ClangTidyValue > OptionMap