/// Parse a function definition signature.
/// func-signature:
/// func-arguments func-throws? func-signature-result?
/// func-signature-result:
/// '->' type
///
/// Note that this leaves retType as null if unspecified.
ParserStatus
Parser::parseFunctionSignature(Identifier SimpleName,
DeclName &FullName,
SmallVectorImpl<ParameterList*> &bodyParams,
DefaultArgumentInfo &defaultArgs,
SourceLoc &throwsLoc,
bool &rethrows,
TypeRepr *&retType) {
SmallVector<Identifier, 4> NamePieces;
NamePieces.push_back(SimpleName);
FullName = SimpleName;
ParserStatus Status;
// We force first type of a func declaration to be a tuple for consistency.
if (Tok.is(tok::l_paren)) {
ParameterContextKind paramContext;
if (SimpleName.isOperator())
paramContext = ParameterContextKind::Operator;
else
paramContext = ParameterContextKind::Function;
Status = parseFunctionArguments(NamePieces, bodyParams, paramContext,
defaultArgs);
FullName = DeclName(Context, SimpleName,
llvm::makeArrayRef(NamePieces.begin() + 1,
NamePieces.end()));
if (bodyParams.empty()) {
// If we didn't get anything, add a () pattern to avoid breaking
// invariants.
assert(Status.hasCodeCompletion() || Status.isError());
bodyParams.push_back(ParameterList::createEmpty(Context));
}
} else {
diagnose(Tok, diag::func_decl_without_paren);
Status = makeParserError();
// Recover by creating a '() -> ?' signature.
bodyParams.push_back(ParameterList::createEmpty(Context, PreviousLoc,
PreviousLoc));
FullName = DeclName(Context, SimpleName, bodyParams.back());
}
// Check for the 'throws' keyword.
rethrows = false;
if (Tok.is(tok::kw_throws)) {
throwsLoc = consumeToken();
} else if (Tok.is(tok::kw_rethrows)) {
throwsLoc = consumeToken();
rethrows = true;
} else if (Tok.is(tok::kw_throw)) {
throwsLoc = consumeToken();
diagnose(throwsLoc, diag::throw_in_function_type)
.fixItReplace(throwsLoc, "throws");
}
SourceLoc arrowLoc;
// If there's a trailing arrow, parse the rest as the result type.
if (Tok.isAny(tok::arrow, tok::colon)) {
if (!consumeIf(tok::arrow, arrowLoc)) {
// FixIt ':' to '->'.
diagnose(Tok, diag::func_decl_expected_arrow)
.fixItReplace(SourceRange(Tok.getLoc()), "->");
arrowLoc = consumeToken(tok::colon);
}
ParserResult<TypeRepr> ResultType =
parseType(diag::expected_type_function_result);
if (ResultType.hasCodeCompletion())
return ResultType;
retType = ResultType.getPtrOrNull();
if (!retType) {
Status.setIsParseError();
return Status;
}
} else {
// Otherwise, we leave retType null.
retType = nullptr;
}
// Check for 'throws' and 'rethrows' after the type and correct it.
if (!throwsLoc.isValid()) {
if (Tok.is(tok::kw_throws)) {
throwsLoc = consumeToken();
} else if (Tok.is(tok::kw_rethrows)) {
throwsLoc = consumeToken();
rethrows = true;
}
if (throwsLoc.isValid()) {
assert(arrowLoc.isValid());
assert(retType);
auto diag = rethrows ? diag::rethrows_after_function_result
: diag::throws_after_function_result;
SourceLoc typeEndLoc = Lexer::getLocForEndOfToken(SourceMgr,
retType->getEndLoc());
SourceLoc throwsEndLoc = Lexer::getLocForEndOfToken(SourceMgr, throwsLoc);
diagnose(Tok, diag)
.fixItInsert(arrowLoc, rethrows ? "rethrows " : "throws ")
.fixItRemoveChars(typeEndLoc, throwsEndLoc);
}
}
return Status;
}
