Private Named Instance Fields Implementation

src/compiler/binder.ts

@@ -3637,6 +3637,10 @@ namespace ts {
         let excludeFlags = TransformFlags.NodeExcludes;
 
         switch (kind) {
+            case SyntaxKind.PrivateName:
+                // Private names are ESNext syntax.
+                transformFlags |= TransformFlags.AssertESNext;
+                break;
             case SyntaxKind.AsyncKeyword:
             case SyntaxKind.AwaitExpression:
                 // async/await is ES2017 syntax, but may be ESNext syntax (for async generators)

src/compiler/transformers/generators.ts

@@ -667,28 +667,6 @@ namespace ts {
             }
         }
 
-        function isCompoundAssignment(kind: BinaryOperator): kind is CompoundAssignmentOperator {
-            return kind >= SyntaxKind.FirstCompoundAssignment
-                && kind <= SyntaxKind.LastCompoundAssignment;
-        }
-
-        function getOperatorForCompoundAssignment(kind: CompoundAssignmentOperator): BitwiseOperatorOrHigher {
-            switch (kind) {
-                case SyntaxKind.PlusEqualsToken: return SyntaxKind.PlusToken;
-                case SyntaxKind.MinusEqualsToken: return SyntaxKind.MinusToken;
-                case SyntaxKind.AsteriskEqualsToken: return SyntaxKind.AsteriskToken;
-                case SyntaxKind.AsteriskAsteriskEqualsToken: return SyntaxKind.AsteriskAsteriskToken;
-                case SyntaxKind.SlashEqualsToken: return SyntaxKind.SlashToken;
-                case SyntaxKind.PercentEqualsToken: return SyntaxKind.PercentToken;
-                case SyntaxKind.LessThanLessThanEqualsToken: return SyntaxKind.LessThanLessThanToken;
-                case SyntaxKind.GreaterThanGreaterThanEqualsToken: return SyntaxKind.GreaterThanGreaterThanToken;
-                case SyntaxKind.GreaterThanGreaterThanGreaterThanEqualsToken: return SyntaxKind.GreaterThanGreaterThanGreaterThanToken;
-                case SyntaxKind.AmpersandEqualsToken: return SyntaxKind.AmpersandToken;
-                case SyntaxKind.BarEqualsToken: return SyntaxKind.BarToken;
-                case SyntaxKind.CaretEqualsToken: return SyntaxKind.CaretToken;
-            }
-        }
-
         /**
          * Visits a right-associative binary expression containing `yield`.
          *

src/compiler/transformers/ts.ts

@@ -929,17 +929,12 @@ namespace ts {
                 const parameters = transformConstructorParameters(constructor);
                 const body = transformConstructorBody(node.members, constructor, parametersWithPropertyAssignments);
                 members.push(startOnNewLine(
-                    setOriginalNode(
-                        setTextRange(
-                            createConstructor(
-                            /*decorators*/ undefined,
-                            /*modifiers*/ undefined,
-                                parameters,
-                                body
-                            ),
-                            constructor
-                        ),
-                        constructor
+                    updateConstructor(
+                        constructor,
+                        /*decorators*/ undefined,
+                        /*modifiers*/ undefined,
+                        parameters,
+                        body
                     )
                 ));
                 addRange(

src/compiler/transformers/utilities.ts

@@ -335,4 +335,26 @@ namespace ts {
         return member.kind === SyntaxKind.PropertyDeclaration
             && (<PropertyDeclaration>member).initializer !== undefined;
     }
+
+    export function isCompoundAssignment(kind: BinaryOperator): kind is CompoundAssignmentOperator {
+        return kind >= SyntaxKind.FirstCompoundAssignment
+            && kind <= SyntaxKind.LastCompoundAssignment;
+    }
+
+    export function getOperatorForCompoundAssignment(kind: CompoundAssignmentOperator): BitwiseOperatorOrHigher {
+        switch (kind) {
+            case SyntaxKind.PlusEqualsToken: return SyntaxKind.PlusToken;
+            case SyntaxKind.MinusEqualsToken: return SyntaxKind.MinusToken;
+            case SyntaxKind.AsteriskEqualsToken: return SyntaxKind.AsteriskToken;
+            case SyntaxKind.AsteriskAsteriskEqualsToken: return SyntaxKind.AsteriskAsteriskToken;
+            case SyntaxKind.SlashEqualsToken: return SyntaxKind.SlashToken;
+            case SyntaxKind.PercentEqualsToken: return SyntaxKind.PercentToken;
+            case SyntaxKind.LessThanLessThanEqualsToken: return SyntaxKind.LessThanLessThanToken;
+            case SyntaxKind.GreaterThanGreaterThanEqualsToken: return SyntaxKind.GreaterThanGreaterThanToken;
+            case SyntaxKind.GreaterThanGreaterThanGreaterThanEqualsToken: return SyntaxKind.GreaterThanGreaterThanGreaterThanToken;
+            case SyntaxKind.AmpersandEqualsToken: return SyntaxKind.AmpersandToken;
+            case SyntaxKind.BarEqualsToken: return SyntaxKind.BarToken;
+            case SyntaxKind.CaretEqualsToken: return SyntaxKind.CaretToken;
+        }
+    }
 }

src/compiler/types.ts

@@ -942,6 +942,10 @@ namespace ts {
         initializer?: Expression;           // Optional initializer
     }
 
+    export interface PrivatePropertyDeclaration extends PropertyDeclaration {
+        name: PrivateName;
+    }
+
     export interface ObjectLiteralElement extends NamedDeclaration {
         _objectLiteralBrandBrand: any;
         name?: PropertyName;
@@ -1752,6 +1756,10 @@ namespace ts {
         name: Identifier | PrivateName;
     }
 
+    export interface PrivateNamedPropertyAccess extends PropertyAccessExpression {
+        name: PrivateName;
+    }
+
     export interface SuperPropertyAccessExpression extends PropertyAccessExpression {
         expression: SuperExpression;
     }

src/compiler/utilities.ts

@@ -6111,6 +6111,14 @@ namespace ts {
             || kind === SyntaxKind.ComputedPropertyName;
     }
 
+    export function isPrivatePropertyDeclaration(node: Node): node is PrivatePropertyDeclaration {
+        return isPropertyDeclaration(node) && isPrivateName(node.name);
+    }
+
+    export function isPrivateNamedPropertyAccess(node: Node): node is PrivateNamedPropertyAccess {
+        return isPropertyAccessExpression(node) && isPrivateName(node.name);
+    }
+
     export function isBindingName(node: Node): node is BindingName {
         const kind = node.kind;
         return kind === SyntaxKind.Identifier

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -621,6 +621,9 @@ declare namespace ts {
         type?: TypeNode;
         initializer?: Expression;
     }
+    interface PrivatePropertyDeclaration extends PropertyDeclaration {
+        name: PrivateName;
+    }
     interface ObjectLiteralElement extends NamedDeclaration {
         _objectLiteralBrandBrand: any;
         name?: PropertyName;
@@ -3480,6 +3483,7 @@ declare namespace ts {
     function isModifier(node: Node): node is Modifier;
     function isEntityName(node: Node): node is EntityName;
     function isPropertyName(node: Node): node is PropertyName;
+    function isPrivatePropertyDeclaration(node: Node): node is PrivatePropertyDeclaration;
     function isBindingName(node: Node): node is BindingName;
     function isFunctionLike(node: Node): node is SignatureDeclaration;
     function isClassElement(node: Node): node is ClassElement;

tests/baselines/reference/api/typescript.d.ts

@@ -621,6 +621,9 @@ declare namespace ts {
         type?: TypeNode;
         initializer?: Expression;
     }
+    interface PrivatePropertyDeclaration extends PropertyDeclaration {
+        name: PrivateName;
+    }
     interface ObjectLiteralElement extends NamedDeclaration {
         _objectLiteralBrandBrand: any;
         name?: PropertyName;
@@ -3480,6 +3483,7 @@ declare namespace ts {
     function isModifier(node: Node): node is Modifier;
     function isEntityName(node: Node): node is EntityName;
     function isPropertyName(node: Node): node is PropertyName;
+    function isPrivatePropertyDeclaration(node: Node): node is PrivatePropertyDeclaration;
     function isBindingName(node: Node): node is BindingName;
     function isFunctionLike(node: Node): node is SignatureDeclaration;
     function isClassElement(node: Node): node is ClassElement;

tests/baselines/reference/privateNameField.js

@@ -7,9 +7,12 @@ class A {
 }
 
 //// [privateNameField.js]
+var _classPrivateFieldSet = function (receiver, privateMap, value) { if (!privateMap.has(receiver)) { throw new TypeError("attempted to set private field on non-instance"); } privateMap.set(receiver, value); return value; };
+var _name;
 var A = /** @class */ (function () {
     function A(name) {
-        this.#name = name;
+        _classPrivateFieldSet(this, _name, name);
     }
     return A;
 }());
+_name = new WeakMap();

tests/baselines/reference/privateNameFieldAccess.js

@@ -0,0 +1,20 @@
+//// [privateNameFieldAccess.ts]
+class A {
+    #myField = "hello world";
+    constructor() {
+        console.log(this.#myField);
+    }
+}
+
+
+//// [privateNameFieldAccess.js]
+var _classPrivateFieldGet = function (receiver, privateMap) { if (!privateMap.has(receiver)) { throw new TypeError("attempted to get private field on non-instance"); } return privateMap.get(receiver); };
+var _myField;
+var A = /** @class */ (function () {
+    function A() {
+        _myField.set(this, "hello world");
+        console.log(_classPrivateFieldGet(this, _myField));
+    }
+    return A;
+}());
+_myField = new WeakMap();

tests/baselines/reference/privateNameFieldAccess.symbols

@@ -0,0 +1,17 @@
+=== tests/cases/conformance/classes/members/privateNames/privateNameFieldAccess.ts ===
+class A {
+>A : Symbol(A, Decl(privateNameFieldAccess.ts, 0, 0))
+
+    #myField = "hello world";
+>#myField : Symbol(A[#myField], Decl(privateNameFieldAccess.ts, 0, 9))
+
+    constructor() {
+        console.log(this.#myField);
+>console.log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>console : Symbol(console, Decl(lib.dom.d.ts, --, --))
+>log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>this.#myField : Symbol(A[#myField], Decl(privateNameFieldAccess.ts, 0, 9))
+>this : Symbol(A, Decl(privateNameFieldAccess.ts, 0, 0))
+    }
+}
+

tests/baselines/reference/privateNameFieldAccess.types

@@ -0,0 +1,19 @@
+=== tests/cases/conformance/classes/members/privateNames/privateNameFieldAccess.ts ===
+class A {
+>A : A
+
+    #myField = "hello world";
+>#myField : string
+>"hello world" : "hello world"
+
+    constructor() {
+        console.log(this.#myField);
+>console.log(this.#myField) : void
+>console.log : (message?: any, ...optionalParams: any[]) => void
+>console : Console
+>log : (message?: any, ...optionalParams: any[]) => void
+>this.#myField : string
+>this : this
+    }
+}
+

tests/baselines/reference/privateNameFieldAssignment.js

@@ -0,0 +1,78 @@
+//// [privateNameFieldAssignment.ts]
+class A {
+    #field = 0;
+    constructor() {
+        this.#field = 1;
+        this.#field += 2;
+        this.#field -= 3;
+        this.#field /= 4;
+        this.#field *= 5;
+        this.#field **= 6;
+        this.#field %= 7;
+        this.#field <<= 8;
+        this.#field >>= 9;
+        this.#field >>>= 10;
+        this.#field &= 11;
+        this.#field |= 12;
+        this.#field ^= 13;
+        A.getInstance().#field = 1;
+        A.getInstance().#field += 2;
+        A.getInstance().#field -= 3;
+        A.getInstance().#field /= 4;
+        A.getInstance().#field *= 5;
+        A.getInstance().#field **= 6;
+        A.getInstance().#field %= 7;
+        A.getInstance().#field <<= 8;
+        A.getInstance().#field >>= 9;
+        A.getInstance().#field >>>= 10;
+        A.getInstance().#field &= 11;
+        A.getInstance().#field |= 12;
+        A.getInstance().#field ^= 13;
+    }
+    static getInstance() {
+        return new A();
+    }
+}
+
+
+//// [privateNameFieldAssignment.js]
+var _classPrivateFieldSet = function (receiver, privateMap, value) { if (!privateMap.has(receiver)) { throw new TypeError("attempted to set private field on non-instance"); } privateMap.set(receiver, value); return value; };
+var _classPrivateFieldGet = function (receiver, privateMap) { if (!privateMap.has(receiver)) { throw new TypeError("attempted to get private field on non-instance"); } return privateMap.get(receiver); };
+var _field;
+var A = /** @class */ (function () {
+    function A() {
+        _field.set(this, 0);
+        var _a, _b, _c, _d, _e, _f, _g, _h, _j, _k, _l, _m;
+        _classPrivateFieldSet(this, _field, 1);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) + 2);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) - 3);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) / 4);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) * 5);
+        _classPrivateFieldSet(this, _field, Math.pow(_classPrivateFieldGet(this, _field), 6));
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) % 7);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) << 8);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) >> 9);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) >>> 10);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) & 11);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) | 12);
+        _classPrivateFieldSet(this, _field, _classPrivateFieldGet(this, _field) ^ 13);
+        _classPrivateFieldSet(A.getInstance(), _field, 1);
+        _classPrivateFieldSet(_a = A.getInstance(), _field, _classPrivateFieldGet(_a, _field) + 2);
+        _classPrivateFieldSet(_b = A.getInstance(), _field, _classPrivateFieldGet(_b, _field) - 3);
+        _classPrivateFieldSet(_c = A.getInstance(), _field, _classPrivateFieldGet(_c, _field) / 4);
+        _classPrivateFieldSet(_d = A.getInstance(), _field, _classPrivateFieldGet(_d, _field) * 5);
+        _classPrivateFieldSet(_e = A.getInstance(), _field, Math.pow(_classPrivateFieldGet(_e, _field), 6));
+        _classPrivateFieldSet(_f = A.getInstance(), _field, _classPrivateFieldGet(_f, _field) % 7);
+        _classPrivateFieldSet(_g = A.getInstance(), _field, _classPrivateFieldGet(_g, _field) << 8);
+        _classPrivateFieldSet(_h = A.getInstance(), _field, _classPrivateFieldGet(_h, _field) >> 9);
+        _classPrivateFieldSet(_j = A.getInstance(), _field, _classPrivateFieldGet(_j, _field) >>> 10);
+        _classPrivateFieldSet(_k = A.getInstance(), _field, _classPrivateFieldGet(_k, _field) & 11);
+        _classPrivateFieldSet(_l = A.getInstance(), _field, _classPrivateFieldGet(_l, _field) | 12);
+        _classPrivateFieldSet(_m = A.getInstance(), _field, _classPrivateFieldGet(_m, _field) ^ 13);
+    }
+    A.getInstance = function () {
+        return new A();
+    };
+    return A;
+}());
+_field = new WeakMap();