void DefaultArgumentsCheck::check(const MatchFinder::MatchResult &Result) {
if (const auto *S =
Result.Nodes.getNodeAs<CXXDefaultArgExpr>("stmt")) {
diag(S->getUsedLocation(),
"calling a function that uses a default argument is disallowed");
diag(S->getParam()->getBeginLoc(), "default parameter was declared here",
DiagnosticIDs::Note);
} else if (const ParmVarDecl *D =
Result.Nodes.getNodeAs<ParmVarDecl>("decl")) {
SourceRange DefaultArgRange = D->getDefaultArgRange();
if (DefaultArgRange.getEnd() != D->getEndLoc()) {
return;
} else if (DefaultArgRange.getBegin().isMacroID()) {
diag(D->getBeginLoc(),
"declaring a parameter with a default argument is disallowed");
} else {
SourceLocation StartLocation =
D->getName().empty() ? D->getBeginLoc() : D->getLocation();
SourceRange RemovalRange(Lexer::getLocForEndOfToken(
StartLocation, 0,
*Result.SourceManager,
Result.Context->getLangOpts()
),
DefaultArgRange.getEnd()
);
diag(D->getBeginLoc(),
"declaring a parameter with a default argument is disallowed")
<< D << FixItHint::CreateRemoval(RemovalRange);
}
}
}
void UnusedParametersCheck::warnOnUnusedParameter(
const MatchFinder::MatchResult &Result, const FunctionDecl *Function,
unsigned ParamIndex) {
const auto *Param = Function->getParamDecl(ParamIndex);
auto MyDiag = diag(Param->getLocation(), "parameter '%0' is unused")
<< Param->getName();
auto UsedByRef = [&] {
return !ast_matchers::match(
decl(hasDescendant(
declRefExpr(to(equalsNode(Function)),
unless(hasAncestor(
callExpr(callee(equalsNode(Function)))))))),
*Result.Context->getTranslationUnitDecl(), *Result.Context)
.empty();
};
// Comment out parameter name for non-local functions.
if (Function->isExternallyVisible() ||
!Result.SourceManager->isInMainFile(Function->getLocation()) ||
UsedByRef()) {
SourceRange RemovalRange(Param->getLocation(), Param->getLocEnd());
// Note: We always add a space before the '/*' to not accidentally create a
// '*/*' for pointer types, which doesn't start a comment. clang-format will
// clean this up afterwards.
MyDiag << FixItHint::CreateReplacement(
RemovalRange, (Twine(" /*") + Param->getName() + "*/").str());
return;
}
// Fix all redeclarations.
for (const FunctionDecl *FD : Function->redecls())
if (FD->param_size())
MyDiag << removeParameter(FD, ParamIndex);
// Fix all call sites.
auto CallMatches = ast_matchers::match(
decl(forEachDescendant(
callExpr(callee(functionDecl(equalsNode(Function)))).bind("x"))),
*Result.Context->getTranslationUnitDecl(), *Result.Context);
for (const auto &Match : CallMatches)
MyDiag << removeArgument(Match.getNodeAs<CallExpr>("x"), ParamIndex);
}
void UnusedParametersCheck::warnOnUnusedParameter(
const MatchFinder::MatchResult &Result, const FunctionDecl *Function,
unsigned ParamIndex) {
const auto *Param = Function->getParamDecl(ParamIndex);
auto MyDiag = diag(Param->getLocation(), "parameter '%0' is unused")
<< Param->getName();
auto UsedByRef = [&] {
return !ast_matchers::match(
decl(hasDescendant(
declRefExpr(to(equalsNode(Function)),
unless(hasAncestor(
callExpr(callee(equalsNode(Function)))))))),
*Result.Context->getTranslationUnitDecl(), *Result.Context)
.empty();
};
// Comment out parameter name for non-local functions.
if ((Function->isExternallyVisible() &&
Function->getStorageClass() != StorageClass::SC_Static) ||
UsedByRef()) {
SourceRange RemovalRange(Param->getLocation(), Param->getLocEnd());
MyDiag << FixItHint::CreateReplacement(
RemovalRange, (Twine(" /*") + Param->getName() + "*/").str());
return;
}
// Fix all redeclarations.
for (const FunctionDecl *FD : Function->redecls())
MyDiag << removeParameter(FD, ParamIndex);
// Fix all call sites.
auto CallMatches = ast_matchers::match(
decl(forEachDescendant(
callExpr(callee(functionDecl(equalsNode(Function)))).bind("x"))),
*Result.Context->getTranslationUnitDecl(), *Result.Context);
for (const auto &Match : CallMatches)
MyDiag << removeArgument(Match.getNodeAs<CallExpr>("x"), ParamIndex);
}