Added extension specialization to libSyntax

Author: sigito

lib/Parse/ParseDecl.cpp

@@ -2416,9 +2416,11 @@ Parser::parseDecl(ParseDeclOptions Flags,
       DeclParsingContext.setCreateSyntax(SyntaxKind::ImportDecl);
       DeclResult = parseDeclImport(Flags, Attributes);
       break;
-    case tok::kw_extension:
+    case tok::kw_extension: {
+      DeclParsingContext.setCreateSyntax(SyntaxKind::ExtensionDecl);
       DeclResult = parseDeclExtension(Flags, Attributes);
       break;
+    }
     case tok::kw_let:
     case tok::kw_var: {
       // Collect all modifiers into a modifier list.
@@ -3063,6 +3065,7 @@ Parser::parseDeclExtension(ParseDeclOptions Flags, DeclAttributes &Attributes) {
                                              trailingWhereClause);
   ext->getAttrs() = Attributes;
 
+  SyntaxParsingContext BlockContext(SyntaxContext, SyntaxKind::MemberDeclBlock);
   SourceLoc LBLoc, RBLoc;
   if (parseToken(tok::l_brace, LBLoc, diag::expected_lbrace_extension)) {
     LBLoc = PreviousLoc;

lib/Syntax/Status.md

@@ -68,9 +68,9 @@
   * IfConfigDecl
   * PatternBindingDecl
   * VarDecl
+  * ExtensionDecl
 
 ### In-progress (UnknownDecl):
-  * ExtensionDecl (SR-6572)
 
 ### Not-started (UnknownDecl):
   * EnumCaseDecl

test/Syntax/Outputs/round_trip_parse_gen.swift.withkinds

@@ -311,4 +311,22 @@ func statementTests<FunctionSignature><ParameterClause>() </ParameterClause></Fu
 
   for <ValueBindingPattern>var <IdentifierPattern>i </IdentifierPattern></ValueBindingPattern>in <IdentifierExpr>foo </IdentifierExpr><WhereClause>where <MemberAccessExpr><IdentifierExpr>i</IdentifierExpr>.foo </MemberAccessExpr></WhereClause><CodeBlock>{}</CodeBlock></ForInStmt><ForInStmt>
   for case <IsTypePattern>is <SimpleTypeIdentifier>Int </SimpleTypeIdentifier></IsTypePattern>in <IdentifierExpr>foo </IdentifierExpr><CodeBlock>{}</CodeBlock></ForInStmt>
-}</CodeBlock></FunctionDecl>
+}</CodeBlock></FunctionDecl><ExtensionDecl>
+
+// MARK: - ExtensionDecl
+
+extension <SimpleTypeIdentifier>ext </SimpleTypeIdentifier><MemberDeclBlock>{<VariableDecl>
+  var <PatternBinding><IdentifierPattern>s</IdentifierPattern><TypeAnnotation>: <SimpleTypeIdentifier>Int </SimpleTypeIdentifier></TypeAnnotation><AccessorBlock>{<ReturnStmt>
+    return <IntegerLiteralExpr>42</IntegerLiteralExpr></ReturnStmt>
+  }</AccessorBlock></PatternBinding></VariableDecl>
+}</MemberDeclBlock></ExtensionDecl><ExtensionDecl><Attribute>
+
+@available(*, unavailable)</Attribute><DeclModifier>
+fileprivate </DeclModifier>extension <SimpleTypeIdentifier>ext </SimpleTypeIdentifier><MemberDeclBlock>{}</MemberDeclBlock></ExtensionDecl><ExtensionDecl>
+
+extension <SimpleTypeIdentifier>ext </SimpleTypeIdentifier><TypeInheritanceClause>: <InheritedType><SimpleTypeIdentifier>extProtocol </SimpleTypeIdentifier></InheritedType></TypeInheritanceClause><MemberDeclBlock>{}</MemberDeclBlock></ExtensionDecl><ExtensionDecl>
+
+extension <SimpleTypeIdentifier>ext </SimpleTypeIdentifier><GenericWhereClause>where <SameTypeRequirement><SimpleTypeIdentifier>A </SimpleTypeIdentifier>== <SimpleTypeIdentifier>Int</SimpleTypeIdentifier>, </SameTypeRequirement><ConformanceRequirement><SimpleTypeIdentifier>B</SimpleTypeIdentifier>: <SimpleTypeIdentifier>Numeric </SimpleTypeIdentifier></ConformanceRequirement></GenericWhereClause><MemberDeclBlock>{}</MemberDeclBlock></ExtensionDecl><ExtensionDecl>
+
+extension <MemberTypeIdentifier><MemberTypeIdentifier><SimpleTypeIdentifier>ext</SimpleTypeIdentifier>.a</MemberTypeIdentifier>.b </MemberTypeIdentifier><MemberDeclBlock>{}</MemberDeclBlock></ExtensionDecl>
+

test/Syntax/round_trip_parse_gen.swift

@@ -312,3 +312,21 @@ func statementTests() {
   for var i in foo where i.foo {}
   for case is Int in foo {}
 }
+
+// MARK: - ExtensionDecl
+
+extension ext {
+  var s: Int {
+    return 42
+  }
+}
+
+@available(*, unavailable)
+fileprivate extension ext {}
+
+extension ext : extProtocol {}
+
+extension ext where A == Int, B: Numeric {}
+
+extension ext.a.b {}
+

utils/gyb_syntax_support/DeclNodes.py

@@ -117,7 +117,7 @@
     #                      generic-parameter-clause?
     #                      type-inheritance-clause?
     #                      generic-where-clause?
-    #                     '{' class-members ''
+    #                     '{' class-members '}'
     # class-name -> identifier
     Node('ClassDecl', kind='Decl',
          children=[
@@ -141,7 +141,7 @@
     #                         generic-parameter-clause?
     #                           type-inheritance-clause?
     #                         generic-where-clause?
-    #                         '{' struct-members ''
+    #                         '{' struct-members '}'
     # struct-name -> identifier
     Node('StructDecl', kind='Decl',
          children=[
@@ -175,6 +175,27 @@
              Child('Members', kind='MemberDeclBlock'),
          ]),
 
+    # extension-declaration -> attributes? access-level-modifier?
+    #                            'extension' extended-type
+    #                              type-inheritance-clause?
+    #                            generic-where-clause?
+    #                            '{' extension-members '}'
+    # extension-name -> identifier
+    Node('ExtensionDecl', kind='Decl',
+         children=[
+             Child('Attributes', kind='AttributeList',
+                   is_optional=True),
+             Child('AccessLevelModifier', kind='DeclModifier',
+                   is_optional=True),
+             Child('ExtensionKeyword', kind='ExtensionToken'),
+             Child('ExtendedType', kind='Type'),
+             Child('InheritanceClause', kind='TypeInheritanceClause',
+                   is_optional=True),
+             Child('GenericWhereClause', kind='GenericWhereClause',
+                   is_optional=True),
+             Child('Members', kind='MemberDeclBlock'),
+         ]),
+
     Node('MemberDeclBlock', kind='Syntax',
          children=[
              Child('LeftBrace', kind='LeftBraceToken'),