🤖 Pick PR #58771 (Allow references to the global Symb...) into release-5.5 (#59378)

TypeScript Bot · weswigham · web-flow · commit c0ded048e0e8 · 2024-07-22T13:43:53.000-07:00
Co-authored-by: Wesley Wigham &lt;wewigham@microsoft.com&gt;
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -1511,6 +1511,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             Debug.assert(isExpressionNode(node));
             return getSymbolAtLocation(node) === undefinedSymbol;
         },
+        isDefinitelyReferenceToGlobalSymbolObject,
     });
     var evaluate = createEvaluator({
         evaluateElementAccessExpression,
@@ -2351,6 +2352,19 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     return checker;
 
+    function isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean {
+        if (!isPropertyAccessExpression(node)) return false;
+        if (!isIdentifier(node.name)) return false;
+        if (!isPropertyAccessExpression(node.expression) && !isIdentifier(node.expression)) return false;
+        if (isIdentifier(node.expression)) {
+            // Exactly `Symbol.something` and `Symbol` either does not resolve or definitely resolves to the global Symbol
+            return idText(node.expression) === "Symbol" && getResolvedSymbol(node.expression) === (getGlobalSymbol("Symbol" as __String, SymbolFlags.Value | SymbolFlags.ExportValue, /*diagnostic*/ undefined) || unknownSymbol);
+        }
+        if (!isIdentifier(node.expression.expression)) return false;
+        // Exactly `globalThis.Symbol.something` and `globalThis` resolves to the global `globalThis`
+        return idText(node.expression.name) === "Symbol" && idText(node.expression.expression) === "globalThis" && getResolvedSymbol(node.expression.expression) === globalThisSymbol;
+    }
+
     function getCachedType(key: string | undefined) {
         return key ? cachedTypes.get(key) : undefined;
     }
@@ -49763,6 +49777,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 return !sym.exports ? [] : nodeBuilder.symbolTableToDeclarationStatements(sym.exports, node, flags, tracker);
             },
             isImportRequiredByAugmentation,
+            isDefinitelyReferenceToGlobalSymbolObject,
         };
 
         function isImportRequiredByAugmentation(node: ImportDeclaration) {
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
@@ -1150,6 +1150,7 @@ export const notImplementedResolver: EmitResolver = {
     isBindingCapturedByNode: notImplemented,
     getDeclarationStatementsForSourceFile: notImplemented,
     isImportRequiredByAugmentation: notImplemented,
+    isDefinitelyReferenceToGlobalSymbolObject: notImplemented,
 };
 
 const enum PipelinePhase {
diff --git a/src/compiler/expressionToTypeNode.ts b/src/compiler/expressionToTypeNode.ts
@@ -350,7 +350,7 @@ export function createSyntacticTypeNodeBuilder(options: CompilerOptions, resolve
             }
             else if (prop.name.kind === SyntaxKind.ComputedPropertyName) {
                 const expression = prop.name.expression;
-                if (!isPrimitiveLiteralValue(expression, /*includeBigInt*/ false)) {
+                if (!isPrimitiveLiteralValue(expression, /*includeBigInt*/ false) && !resolver.isDefinitelyReferenceToGlobalSymbolObject(expression)) {
                     context.tracker.reportInferenceFallback(prop.name);
                     result = false;
                 }
diff --git a/src/compiler/transformers/declarations.ts b/src/compiler/transformers/declarations.ts
@@ -1001,17 +1001,19 @@ export function transformDeclarations(context: TransformationContext) {
                 if (isolatedDeclarations) {
                     // Classes and object literals usually elide properties with computed names that are not of a literal type
                     // In isolated declarations TSC needs to error on these as we don't know the type in a DTE.
-                    if (isClassDeclaration(input.parent) || isObjectLiteralExpression(input.parent)) {
-                        context.addDiagnostic(createDiagnosticForNode(input, Diagnostics.Computed_property_names_on_class_or_object_literals_cannot_be_inferred_with_isolatedDeclarations));
-                        return;
-                    }
-                    else if (
-                        // Type declarations just need to double-check that the input computed name is an entity name expression
-                        (isInterfaceDeclaration(input.parent) || isTypeLiteralNode(input.parent))
-                        && !isEntityNameExpression(input.name.expression)
-                    ) {
-                        context.addDiagnostic(createDiagnosticForNode(input, Diagnostics.Computed_properties_must_be_number_or_string_literals_variables_or_dotted_expressions_with_isolatedDeclarations));
-                        return;
+                    if (!resolver.isDefinitelyReferenceToGlobalSymbolObject(input.name.expression)) {
+                        if (isClassDeclaration(input.parent) || isObjectLiteralExpression(input.parent)) {
+                            context.addDiagnostic(createDiagnosticForNode(input, Diagnostics.Computed_property_names_on_class_or_object_literals_cannot_be_inferred_with_isolatedDeclarations));
+                            return;
+                        }
+                        else if (
+                            // Type declarations just need to double-check that the input computed name is an entity name expression
+                            (isInterfaceDeclaration(input.parent) || isTypeLiteralNode(input.parent))
+                            && !isEntityNameExpression(input.name.expression)
+                        ) {
+                            context.addDiagnostic(createDiagnosticForNode(input, Diagnostics.Computed_properties_must_be_number_or_string_literals_variables_or_dotted_expressions_with_isolatedDeclarations));
+                            return;
+                        }
                     }
                 }
                 else if (!resolver.isLateBound(getParseTreeNode(input) as Declaration) || !isEntityNameExpression(input.name.expression)) {
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
@@ -5744,6 +5744,7 @@ export interface EmitResolver {
     isBindingCapturedByNode(node: Node, decl: VariableDeclaration | BindingElement): boolean;
     getDeclarationStatementsForSourceFile(node: SourceFile, flags: NodeBuilderFlags, tracker: SymbolTracker): Statement[] | undefined;
     isImportRequiredByAugmentation(decl: ImportDeclaration): boolean;
+    isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean;
 }
 
 // dprint-ignore
@@ -10270,4 +10271,5 @@ export interface SyntacticTypeNodeBuilderResolver {
     getAllAccessorDeclarations(declaration: AccessorDeclaration): AllAccessorDeclarations;
     isEntityNameVisible(entityName: EntityNameOrEntityNameExpression, enclosingDeclaration: Node, shouldComputeAliasToMakeVisible?: boolean): SymbolVisibilityResult;
     requiresAddingImplicitUndefined(parameter: ParameterDeclaration | JSDocParameterTag): boolean;
+    isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean;
 }
diff --git a/tests/baselines/reference/transpile/declarationComputedPropertyNames.d.ts b/tests/baselines/reference/transpile/declarationComputedPropertyNames.d.ts
@@ -3,11 +3,16 @@ export namespace presentNs {
     export const a = Symbol();
 }
 
+const aliasing = Symbol;
+
 export type A = {
     [missing]: number,
     [ns.missing]: number,
     [presentNs.a]: number,
     [Symbol.iterator]: number,
+    [globalThis.Symbol.toStringTag]: number,
+    [(globalThis.Symbol).unscopables]: number,
+    [aliasing.isConcatSpreadable]: number,
     [1]: number,
     ["2"]: number,
     [(missing2)]: number,
@@ -19,6 +24,9 @@ export interface B {
     [ns.missing]: number,
     [presentNs.a]: number,
     [Symbol.iterator]: number,
+    [globalThis.Symbol.toStringTag]: number,
+    [(globalThis.Symbol).unscopables]: number,
+    [aliasing.isConcatSpreadable]: number,
     [1]: number,
     ["2"]: number,
     [(missing2)]: number,
@@ -30,6 +38,9 @@ export class C {
     [ns.missing]: number = 1;
     [presentNs.a]: number = 1;
     [Symbol.iterator]: number = 1;
+    [globalThis.Symbol.toStringTag]: number = 1;
+    [(globalThis.Symbol).unscopables]: number = 1;
+    [aliasing.isConcatSpreadable]: number = 1;
     [1]: number = 1;
     ["2"]: number = 1;
     [(missing2)]: number = 1;
@@ -41,6 +52,9 @@ export const D = {
     [ns.missing]: 1,
     [presentNs.a]: 1,
     [Symbol.iterator]: 1,
+    [globalThis.Symbol.toStringTag]: 1,
+    [(globalThis.Symbol).unscopables]: 1,
+    [aliasing.isConcatSpreadable]: 1,
     [1]: 1,
     ["2"]: 1,
     [(missing2)]: 1,
@@ -50,11 +64,14 @@ export const D = {
 export declare namespace presentNs {
     const a: unique symbol;
 }
+declare const aliasing: SymbolConstructor;
 export type A = {
     [missing]: number;
     [ns.missing]: number;
     [presentNs.a]: number;
     [Symbol.iterator]: number;
+    [globalThis.Symbol.toStringTag]: number;
+    [aliasing.isConcatSpreadable]: number;
     [1]: number;
     ["2"]: number;
 };
@@ -63,55 +80,76 @@ export interface B {
     [ns.missing]: number;
     [presentNs.a]: number;
     [Symbol.iterator]: number;
+    [globalThis.Symbol.toStringTag]: number;
+    [aliasing.isConcatSpreadable]: number;
     [1]: number;
     ["2"]: number;
 }
 export declare class C {
+    [Symbol.iterator]: number;
+    [globalThis.Symbol.toStringTag]: number;
     [1]: number;
     ["2"]: number;
 }
 export declare const D: {
     [x: string]: number;
     [x: number]: number;
     [presentNs.a]: number;
+    [aliasing.toStringTag]: number;
     1: number;
     "2": number;
 };
+export {};
 
 
 //// [Diagnostics reported]
 declarationComputedPropertyNames.ts(2,18): error TS9010: Variable must have an explicit type annotation with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(12,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(5,7): error TS9010: Variable must have an explicit type annotation with --isolatedDeclarations.
 declarationComputedPropertyNames.ts(13,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(23,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(24,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(28,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(29,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(30,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(31,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(34,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(35,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(39,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-declarationComputedPropertyNames.ts(40,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(17,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(18,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(27,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(31,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(32,5): error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(36,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(37,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(38,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 declarationComputedPropertyNames.ts(41,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 declarationComputedPropertyNames.ts(42,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 declarationComputedPropertyNames.ts(45,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 declarationComputedPropertyNames.ts(46,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(50,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(51,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(52,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(55,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(56,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(59,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+declarationComputedPropertyNames.ts(60,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 
 
-==== declarationComputedPropertyNames.ts (17 errors) ====
+==== declarationComputedPropertyNames.ts (22 errors) ====
     export namespace presentNs {
         export const a = Symbol();
                      ~
 !!! error TS9010: Variable must have an explicit type annotation with --isolatedDeclarations.
 !!! related TS9027 declarationComputedPropertyNames.ts:2:18: Add a type annotation to the variable a.
     }
     
+    const aliasing = Symbol;
+          ~~~~~~~~
+!!! error TS9010: Variable must have an explicit type annotation with --isolatedDeclarations.
+!!! related TS9027 declarationComputedPropertyNames.ts:5:7: Add a type annotation to the variable aliasing.
+    
     export type A = {
         [missing]: number,
         [ns.missing]: number,
         [presentNs.a]: number,
         [Symbol.iterator]: number,
+        [globalThis.Symbol.toStringTag]: number,
+        [(globalThis.Symbol).unscopables]: number,
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+        [aliasing.isConcatSpreadable]: number,
         [1]: number,
         ["2"]: number,
         [(missing2)]: number,
@@ -127,6 +165,11 @@ declarationComputedPropertyNames.ts(46,5): error TS9038: Computed property names
         [ns.missing]: number,
         [presentNs.a]: number,
         [Symbol.iterator]: number,
+        [globalThis.Symbol.toStringTag]: number,
+        [(globalThis.Symbol).unscopables]: number,
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS9014: Computed properties must be number or string literals, variables or dotted expressions with --isolatedDeclarations.
+        [aliasing.isConcatSpreadable]: number,
         [1]: number,
         ["2"]: number,
         [(missing2)]: number,
@@ -148,7 +191,12 @@ declarationComputedPropertyNames.ts(46,5): error TS9038: Computed property names
         ~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
         [Symbol.iterator]: number = 1;
-        ~~~~~~~~~~~~~~~~~
+        [globalThis.Symbol.toStringTag]: number = 1;
+        [(globalThis.Symbol).unscopables]: number = 1;
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+        [aliasing.isConcatSpreadable]: number = 1;
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
         [1]: number = 1;
         ["2"]: number = 1;
@@ -164,28 +212,34 @@ declarationComputedPropertyNames.ts(46,5): error TS9038: Computed property names
         [missing]: 1,
         ~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
         [ns.missing]: 1,
         ~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
         [presentNs.a]: 1,
         ~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
         [Symbol.iterator]: 1,
-        ~~~~~~~~~~~~~~~~~
+        [globalThis.Symbol.toStringTag]: 1,
+        [(globalThis.Symbol).unscopables]: 1,
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
+        [aliasing.isConcatSpreadable]: 1,
+        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
         [1]: 1,
         ["2"]: 1,
         [(missing2)]: 1,
         ~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
         [Math.random() > 0.5 ? "f1" : "f2"]: 1,
         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
-!!! related TS9027 declarationComputedPropertyNames.ts:38:14: Add a type annotation to the variable D.
+!!! related TS9027 declarationComputedPropertyNames.ts:49:14: Add a type annotation to the variable D.
     };
     
diff --git a/tests/cases/transpile/declarationComputedPropertyNames.ts b/tests/cases/transpile/declarationComputedPropertyNames.ts

Original file line number	Diff line number	Diff line change
`@@ -350,7 +350,7 @@ export function createSyntacticTypeNodeBuilder(options: CompilerOptions, resolve`
`350`	`350`	`}`
`351`	`351`	`else if (prop.name.kind === SyntaxKind.ComputedPropertyName) {`
`352`	`352`	`const expression = prop.name.expression;`
`353`		`- if (!isPrimitiveLiteralValue(expression, /includeBigInt/ false)) {`
	`353`	`+ if (!isPrimitiveLiteralValue(expression, /includeBigInt/ false) && !resolver.isDefinitelyReferenceToGlobalSymbolObject(expression)) {`
`354`	`354`	`context.tracker.reportInferenceFallback(prop.name);`
`355`	`355`	`result = false;`
`356`	`356`	`}`
Original file line number	Diff line number	Diff line change
`@@ -5744,6 +5744,7 @@ export interface EmitResolver {`
`5744`	`5744`	`isBindingCapturedByNode(node: Node, decl: VariableDeclaration \| BindingElement): boolean;`
`5745`	`5745`	`getDeclarationStatementsForSourceFile(node: SourceFile, flags: NodeBuilderFlags, tracker: SymbolTracker): Statement[] \| undefined;`
`5746`	`5746`	`isImportRequiredByAugmentation(decl: ImportDeclaration): boolean;`
	`5747`	`+ isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean;`
`5747`	`5748`	`}`
`5748`	`5749`
`5749`	`5750`	`// dprint-ignore`
`@@ -10270,4 +10271,5 @@ export interface SyntacticTypeNodeBuilderResolver {`
`10270`	`10271`	`getAllAccessorDeclarations(declaration: AccessorDeclaration): AllAccessorDeclarations;`
`10271`	`10272`	`isEntityNameVisible(entityName: EntityNameOrEntityNameExpression, enclosingDeclaration: Node, shouldComputeAliasToMakeVisible?: boolean): SymbolVisibilityResult;`
`10272`	`10273`	`requiresAddingImplicitUndefined(parameter: ParameterDeclaration \| JSDocParameterTag): boolean;`
	`10274`	`+ isDefinitelyReferenceToGlobalSymbolObject(node: Node): boolean;`
`10273`	`10275`	`}`