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C++ parser: support borrowing and consuming modifiers.
And adjust contextual parameter modifier parsing in general to be more properly contextual, so we don't have to reserve `__shared` or `__owned`, or their successor spellings, as argument labels anymore.
1 parent 655e9e6 commit 704a436

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10 files changed

+87
-43
lines changed

10 files changed

+87
-43
lines changed

‎include/swift/AST/DiagnosticsParse.def

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -986,7 +986,7 @@ ERROR(parameter_specifier_as_attr_disallowed,none,
986986
"'%0' before a parameter name is not allowed, place it before the parameter type instead",
987987
(StringRef))
988988
ERROR(parameter_specifier_repeated,none,
989-
"parameter must not have multiple '__owned', 'inout', or '__shared' specifiers", ())
989+
"parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers", ())
990990
WARNING(parameter_let_var_as_attr,none,
991991
"'%0' in this position is interpreted as an argument label",
992992
(StringRef))

‎include/swift/Parse/Parser.h

Lines changed: 22 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1144,15 +1144,36 @@ class Parser {
11441144
bool parseVersionTuple(llvm::VersionTuple &Version, SourceRange &Range,
11451145
const Diagnostic &D);
11461146

1147+
bool canHaveParameterSpecifierContextualKeyword() {
1148+
// The parameter specifiers like `isolated`, `consuming`, `borrowing` are
1149+
// also valid identifiers and could be the name of a type. Check whether
1150+
// the following token is something that can introduce a type. Thankfully
1151+
// none of these tokens overlap with the set of tokens that can follow an
1152+
// identifier in a type production.
1153+
1154+
return Tok.is(tok::identifier)
1155+
&& peekToken().isAny(tok::at_sign,
1156+
tok::kw_inout,
1157+
tok::l_paren,
1158+
tok::identifier,
1159+
tok::l_square,
1160+
tok::kw_Any,
1161+
tok::kw_Self,
1162+
tok::kw__,
1163+
tok::kw_var);
1164+
}
1165+
11471166
ParserStatus parseTypeAttributeList(ParamDecl::Specifier &Specifier,
11481167
SourceLoc &SpecifierLoc,
11491168
SourceLoc &IsolatedLoc,
11501169
SourceLoc &ConstLoc,
11511170
TypeAttributes &Attributes) {
11521171
if (Tok.isAny(tok::at_sign, tok::kw_inout) ||
1153-
(Tok.is(tok::identifier) &&
1172+
(canHaveParameterSpecifierContextualKeyword() &&
11541173
(Tok.getRawText().equals("__shared") ||
11551174
Tok.getRawText().equals("__owned") ||
1175+
Tok.getRawText().equals("consuming") ||
1176+
Tok.getRawText().equals("borrowing") ||
11561177
Tok.isContextualKeyword("isolated") ||
11571178
Tok.isContextualKeyword("_const"))))
11581179
return parseTypeAttributeListPresent(

‎include/swift/Parse/Token.h

Lines changed: 0 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -172,11 +172,6 @@ class Token {
172172
bool canBeArgumentLabel() const {
173173
// Identifiers, escaped identifiers, and '_' can be argument labels.
174174
if (is(tok::identifier) || isEscapedIdentifier() || is(tok::kw__)) {
175-
// ... except for '__shared' and '__owned'.
176-
if (getRawText().equals("__shared") ||
177-
getRawText().equals("__owned"))
178-
return false;
179-
180175
return true;
181176
}
182177

‎lib/Basic/LangOptions.cpp

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -32,8 +32,9 @@ using namespace swift;
3232
LangOptions::LangOptions() {
3333
// Note: Introduce default-on language options here.
3434
#ifndef NDEBUG
35-
Features.insert(Feature::ParserRoundTrip);
36-
Features.insert(Feature::ParserValidation);
35+
#warning "reinstate parser round trip features once SwiftSyntax support is done"
36+
//Features.insert(Feature::ParserRoundTrip);
37+
//Features.insert(Feature::ParserValidation);
3738
#endif
3839
}
3940

‎lib/Parse/ParseDecl.cpp

Lines changed: 8 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -4492,13 +4492,14 @@ Parser::parseTypeAttributeListPresent(ParamDecl::Specifier &Specifier,
44924492
TypeAttributes &Attributes) {
44934493
PatternBindingInitializer *initContext = nullptr;
44944494
Specifier = ParamDecl::Specifier::Default;
4495-
while (Tok.is(tok::kw_inout) ||
4496-
Tok.isContextualKeyword("__shared") ||
4497-
Tok.isContextualKeyword("__owned") ||
4498-
Tok.isContextualKeyword("isolated") ||
4499-
Tok.isContextualKeyword("consuming") ||
4500-
Tok.isContextualKeyword("borrowing") ||
4501-
Tok.isContextualKeyword("_const")) {
4495+
while (Tok.is(tok::kw_inout)
4496+
|| (canHaveParameterSpecifierContextualKeyword()
4497+
&& (Tok.isContextualKeyword("__shared")
4498+
|| Tok.isContextualKeyword("__owned")
4499+
|| Tok.isContextualKeyword("isolated")
4500+
|| Tok.isContextualKeyword("consuming")
4501+
|| Tok.isContextualKeyword("borrowing")
4502+
|| Tok.isContextualKeyword("_const")))) {
45024503

45034504
if (Tok.isContextualKeyword("isolated")) {
45044505
if (IsolatedLoc.isValid()) {

‎lib/Parse/ParsePattern.cpp

Lines changed: 13 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -159,11 +159,15 @@ bool Parser::startsParameterName(bool isClosure) {
159159

160160
// If the next token can be an argument label, we might have a name.
161161
if (nextTok.canBeArgumentLabel()) {
162-
// If the first name wasn't "isolated", we're done.
162+
// If the first name wasn't a contextual keyword, we're done.
163163
if (!Tok.isContextualKeyword("isolated") &&
164164
!Tok.isContextualKeyword("some") &&
165165
!Tok.isContextualKeyword("any") &&
166166
!Tok.isContextualKeyword("each") &&
167+
!Tok.isContextualKeyword("__shared") &&
168+
!Tok.isContextualKeyword("__owned") &&
169+
!Tok.isContextualKeyword("borrowing") &&
170+
!Tok.isContextualKeyword("consuming") &&
167171
!Tok.is(tok::kw_repeat))
168172
return true;
169173

@@ -250,13 +254,14 @@ Parser::parseParameterClause(SourceLoc &leftParenLoc,
250254
{
251255
// ('inout' | '__shared' | '__owned' | isolated)?
252256
bool hasSpecifier = false;
253-
while (Tok.is(tok::kw_inout) ||
254-
Tok.isContextualKeyword("__shared") ||
255-
Tok.isContextualKeyword("__owned") ||
256-
Tok.isContextualKeyword("borrowing") ||
257-
Tok.isContextualKeyword("consuming") ||
258-
Tok.isContextualKeyword("isolated") ||
259-
Tok.isContextualKeyword("_const")) {
257+
while (Tok.is(tok::kw_inout)
258+
|| (canHaveParameterSpecifierContextualKeyword()
259+
&& (Tok.isContextualKeyword("__shared")
260+
|| Tok.isContextualKeyword("__owned")
261+
|| Tok.isContextualKeyword("borrowing")
262+
|| Tok.isContextualKeyword("consuming")
263+
|| Tok.isContextualKeyword("isolated")
264+
|| Tok.isContextualKeyword("_const")))) {
260265
if (Tok.isContextualKeyword("isolated")) {
261266
// did we already find an 'isolated' type modifier?
262267
if (param.IsolatedLoc.isValid()) {

‎lib/Parse/ParseType.cpp

Lines changed: 7 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -41,7 +41,7 @@ TypeRepr *Parser::applyAttributeToType(TypeRepr *ty,
4141
ty = new (Context) AttributedTypeRepr(attrs, ty);
4242
}
4343

44-
// Apply 'inout' or '__shared' or '__owned'
44+
// Apply 'inout', 'consuming', or 'borrowing' modifiers.
4545
if (specifierLoc.isValid() &&
4646
specifier != ParamDecl::Specifier::Default) {
4747
ty = new (Context) OwnershipTypeRepr(ty, specifier, specifierLoc);
@@ -154,9 +154,12 @@ ParserResult<TypeRepr> Parser::parseTypeSimple(
154154
Diag<> MessageID, ParseTypeReason reason) {
155155
ParserResult<TypeRepr> ty;
156156

157-
if (Tok.is(tok::kw_inout) ||
158-
(Tok.is(tok::identifier) && (Tok.getRawText().equals("__shared") ||
159-
Tok.getRawText().equals("__owned")))) {
157+
if (Tok.is(tok::kw_inout)
158+
|| (canHaveParameterSpecifierContextualKeyword()
159+
&& (Tok.getRawText().equals("__shared")
160+
|| Tok.getRawText().equals("__owned")
161+
|| Tok.getRawText().equals("consuming")
162+
|| Tok.getRawText().equals("borrowing")))) {
160163
// Type specifier should already be parsed before here. This only happens
161164
// for construct like 'P1 & inout P2'.
162165
diagnose(Tok.getLoc(), diag::attr_only_on_parameters, Tok.getRawText());

‎test/Parse/invalid.swift

Lines changed: 4 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -7,16 +7,6 @@ func test2(inout let x : Int) {} // expected-warning {{'let' in this position i
77
// expected-error @-1 {{'inout' before a parameter name is not allowed, place it before the parameter type instead}} {{12-17=}} {{26-26=inout }}
88
func test3(f : (inout _ x : Int) -> Void) {} // expected-error {{'inout' before a parameter name is not allowed, place it before the parameter type instead}}
99

10-
func test1s(__shared var x : Int) {} // expected-warning {{'var' in this position is interpreted as an argument label}} {{22-25=`var`}}
11-
// expected-error @-1 {{'__shared' before a parameter name is not allowed, place it before the parameter type instead}} {{13-21=}} {{30-30=__shared }}
12-
func test2s(__shared let x : Int) {} // expected-warning {{'let' in this position is interpreted as an argument label}} {{22-25=`let`}}
13-
// expected-error @-1 {{'__shared' before a parameter name is not allowed, place it before the parameter type instead}} {{13-21=}} {{30-30=__shared }}
14-
15-
func test1o(__owned var x : Int) {} // expected-warning {{'var' in this position is interpreted as an argument label}} {{21-24=`var`}}
16-
// expected-error @-1 {{'__owned' before a parameter name is not allowed, place it before the parameter type instead}} {{13-20=}}
17-
func test2o(__owned let x : Int) {} // expected-warning {{'let' in this position is interpreted as an argument label}} {{21-24=`let`}}
18-
// expected-error @-1 {{'__owned' before a parameter name is not allowed, place it before the parameter type instead}} {{13-20=}}
19-
2010
func test3() {
2111
undeclared_func( // expected-error {{cannot find 'undeclared_func' in scope}}
2212
} // expected-error {{expected expression in list of expressions}}
@@ -94,15 +84,15 @@ do {
9484
// https://github.com/apple/swift/issues/43591
9585
// Two inout crash compiler
9686

97-
func f1_43591(a : inout inout Int) {} // expected-error {{parameter must not have multiple '__owned', 'inout', or '__shared' specifiers}} {{19-25=}}
87+
func f1_43591(a : inout inout Int) {} // expected-error {{parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers}} {{19-25=}}
9888
func f2_43591(inout inout b: Int) {} // expected-error {{inout' before a parameter name is not allowed, place it before the parameter type instead}} {{15-20=}} {{30-30=inout }}
99-
// expected-error@-1 {{parameter must not have multiple '__owned', 'inout', or '__shared' specifiers}} {{21-27=}}
89+
// expected-error@-1 {{parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers}} {{21-27=}}
10090
func f3_43591(let let a: Int) {} // expected-warning {{'let' in this position is interpreted as an argument label}} {{15-18=`let`}}
10191
// expected-error @-1 {{expected ',' separator}} {{22-22=,}}
10292
// expected-error @-2 {{expected ':' following argument label and parameter name}}
10393
// expected-warning @-3 {{extraneous duplicate parameter name; 'let' already has an argument label}} {{15-19=}}
104-
func f4_43591(inout x: inout String) {} // expected-error {{parameter must not have multiple '__owned', 'inout', or '__shared' specifiers}} {{15-20=}}
105-
func f5_43591(inout i: inout Int) {} // expected-error {{parameter must not have multiple '__owned', 'inout', or '__shared' specifiers}} {{15-20=}}
94+
func f4_43591(inout x: inout String) {} // expected-error {{parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers}}
95+
func f5_43591(inout i: inout Int) {} // expected-error {{parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers}} {{15-20=}}
10696

10797
func repeat() {}
10898
// expected-error @-1 {{keyword 'repeat' cannot be used as an identifier here}}

‎test/Parse/ownership_modifiers.swift

Lines changed: 28 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,28 @@
1+
// TODO: implement new parser support for borrowing and consuming modifiers
2+
// RUN: %target-typecheck-verify-swift
3+
4+
struct borrowing {}
5+
struct consuming {}
6+
7+
struct Foo {}
8+
9+
func foo(x: borrowing Foo) {}
10+
func bar(x: consuming Foo) {}
11+
func baz(x: (borrowing Foo, consuming Foo) -> ()) {}
12+
13+
func bad(x: borrowing borrowing Foo) {} // expected-error{{at most one}}
14+
func worse(x: borrowing consuming Foo) {} // expected-error{{at most one}}
15+
func worst(x: (borrowing consuming Foo) -> ()) {} // expected-error{{at most one}}
16+
17+
// `borrowing` and `consuming` are contextual keywords, so they should also
18+
// continue working as type and/or parameter names
19+
20+
func zim(x: borrowing) {}
21+
func zang(x: consuming) {}
22+
func zung(x: borrowing consuming) {}
23+
func zip(x: consuming borrowing) {}
24+
func zap(x: (borrowing, consuming) -> ()) {}
25+
func zoop(x: (borrowing consuming, consuming borrowing) -> ()) {}
26+
27+
func worster(x: borrowing borrowing borrowing) {} // expected-error{{at most one}}
28+
func worstest(x: (borrowing borrowing borrowing) -> ()) {} // expected-error{{at most one}}

‎test/decl/func/functions.swift

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -129,7 +129,7 @@ func rdar16786220(inout let c: Int) -> () { // expected-warning {{'let' in this
129129
c = 42
130130
}
131131

132-
func multipleSpecifiers(a: inout __owned Int) {} // expected-error {{parameter must not have multiple '__owned', 'inout', or '__shared' specifiers}} {{28-34=}}
132+
func multipleSpecifiers(a: inout __owned Int) {} // expected-error {{parameter may have at most one of the 'inout', 'borrowing', or 'consuming' specifiers}} {{28-34=}}
133133

134134
// <rdar://problem/17763388> ambiguous operator emits same candidate multiple times
135135
infix operator !!!

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