fix(25083): allow element access expressions with string or numeric literal arguments as computed properties

Author: hayatexe

src/compiler/checker.ts

@@ -13785,12 +13785,22 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             && isTypeUsableAsIndexSignature(isComputedPropertyName(node) ? checkComputedPropertyName(node) : checkExpressionCached((node as ElementAccessExpression).argumentExpression));
     }
 
+    function isEntityNameExpressionOrElementAccess(node: Node): boolean {
+        if (isEntityNameExpression(node)) {
+            return true;
+        }
+        if (isElementAccessExpression(node) && isStringOrNumericLiteralLike(skipParentheses(node.argumentExpression))) {
+            return isEntityNameExpressionOrElementAccess(node.expression);
+        }
+        return false;
+    }
+
     function isLateBindableAST(node: DeclarationName) {
         if (!isComputedPropertyName(node) && !isElementAccessExpression(node)) {
             return false;
         }
         const expr = isComputedPropertyName(node) ? node.expression : node.argumentExpression;
-        return isEntityNameExpression(expr);
+        return isEntityNameExpressionOrElementAccess(expr);
     }
 
     function isTypeUsableAsIndexSignature(type: Type): boolean {
@@ -52956,7 +52966,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     function checkGrammarForInvalidDynamicName(node: DeclarationName, message: DiagnosticMessage) {
         // Even non-bindable names are allowed as late-bound implied index signatures so long as the name is a simple `a.b.c` type name expression
-        if (isNonBindableDynamicName(node) && !isEntityNameExpression(isElementAccessExpression(node) ? skipParentheses(node.argumentExpression) : (node as ComputedPropertyName).expression)) {
+        if (isNonBindableDynamicName(node) && !isEntityNameExpressionOrElementAccess(isElementAccessExpression(node) ? skipParentheses(node.argumentExpression) : (node as ComputedPropertyName).expression)) {
             return grammarErrorOnNode(node, message);
         }
     }

tests/baselines/reference/computedPropertyWithEnumKey.js

@@ -0,0 +1,13 @@
+//// [tests/cases/compiler/computedPropertyWithEnumKey.ts] ////
+
+//// [computedPropertyWithEnumKey.ts]
+enum Type { Foo = 'foo', '3x14' = '3.14' } type TypeMap = { [Type.Foo]: any; [Type['3x14']]: any; };
+
+
+//// [computedPropertyWithEnumKey.js]
+"use strict";
+var Type;
+(function (Type) {
+    Type["Foo"] = "foo";
+    Type["3x14"] = "3.14";
+})(Type || (Type = {}));

tests/baselines/reference/computedPropertyWithEnumKey.symbols

@@ -0,0 +1,16 @@
+//// [tests/cases/compiler/computedPropertyWithEnumKey.ts] ////
+
+=== computedPropertyWithEnumKey.ts ===
+enum Type { Foo = 'foo', '3x14' = '3.14' } type TypeMap = { [Type.Foo]: any; [Type['3x14']]: any; };
+>Type : Symbol(Type, Decl(computedPropertyWithEnumKey.ts, 0, 0))
+>Foo : Symbol(Type.Foo, Decl(computedPropertyWithEnumKey.ts, 0, 11))
+>'3x14' : Symbol(Type['3x14'], Decl(computedPropertyWithEnumKey.ts, 0, 24))
+>TypeMap : Symbol(TypeMap, Decl(computedPropertyWithEnumKey.ts, 0, 42))
+>[Type.Foo] : Symbol([Type.Foo], Decl(computedPropertyWithEnumKey.ts, 0, 59))
+>Type.Foo : Symbol(Type.Foo, Decl(computedPropertyWithEnumKey.ts, 0, 11))
+>Type : Symbol(Type, Decl(computedPropertyWithEnumKey.ts, 0, 0))
+>Foo : Symbol(Type.Foo, Decl(computedPropertyWithEnumKey.ts, 0, 11))
+>[Type['3x14']] : Symbol([Type['3x14']], Decl(computedPropertyWithEnumKey.ts, 0, 76))
+>Type : Symbol(Type, Decl(computedPropertyWithEnumKey.ts, 0, 0))
+>'3x14' : Symbol(Type['3x14'], Decl(computedPropertyWithEnumKey.ts, 0, 24))
+

tests/baselines/reference/computedPropertyWithEnumKey.types

@@ -0,0 +1,31 @@
+//// [tests/cases/compiler/computedPropertyWithEnumKey.ts] ////
+
+=== computedPropertyWithEnumKey.ts ===
+enum Type { Foo = 'foo', '3x14' = '3.14' } type TypeMap = { [Type.Foo]: any; [Type['3x14']]: any; };
+>Type : Type
+>     : ^^^^
+>Foo : Type.Foo
+>    : ^^^^^^^^
+>'foo' : "foo"
+>      : ^^^^^
+>'3x14' : (typeof Type)["3x14"]
+>       : ^^^^^^^^^^^^^^^^^^^^^
+>'3.14' : "3.14"
+>       : ^^^^^^
+>TypeMap : TypeMap
+>        : ^^^^^^^
+>[Type.Foo] : any
+>Type.Foo : Type.Foo
+>         : ^^^^^^^^
+>Type : typeof Type
+>     : ^^^^^^^^^^^
+>Foo : Type.Foo
+>    : ^^^^^^^^
+>[Type['3x14']] : any
+>Type['3x14'] : (typeof Type)["3x14"]
+>             : ^^^^^^^^^^^^^^^^^^^^^
+>Type : typeof Type
+>     : ^^^^^^^^^^^
+>'3x14' : "3x14"
+>       : ^^^^^^
+

tests/baselines/reference/isolatedDeclarationLazySymbols.errors.txt

@@ -1,6 +1,6 @@
 isolatedDeclarationLazySymbols.ts(1,17): error TS9007: Function must have an explicit return type annotation with --isolatedDeclarations.
+isolatedDeclarationLazySymbols.ts(12,1): error TS9023: Assigning properties to functions without declaring them is not supported with --isolatedDeclarations. Add an explicit declaration for the properties assigned to this function.
 isolatedDeclarationLazySymbols.ts(13,1): error TS9023: Assigning properties to functions without declaring them is not supported with --isolatedDeclarations. Add an explicit declaration for the properties assigned to this function.
-isolatedDeclarationLazySymbols.ts(16,5): error TS1166: A computed property name in a class property declaration must have a simple literal type or a 'unique symbol' type.
 isolatedDeclarationLazySymbols.ts(16,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 isolatedDeclarationLazySymbols.ts(21,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
 isolatedDeclarationLazySymbols.ts(22,5): error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
@@ -22,15 +22,15 @@ isolatedDeclarationLazySymbols.ts(22,5): error TS9038: Computed property names o
     } as const
 
     foo[o["prop.inner"]] ="A";
+    ~~~~~~~~~~~~~~~~~~~~
+!!! error TS9023: Assigning properties to functions without declaring them is not supported with --isolatedDeclarations. Add an explicit declaration for the properties assigned to this function.
     foo[o.prop.inner] = "B";
     ~~~~~~~~~~~~~~~~~
 !!! error TS9023: Assigning properties to functions without declaring them is not supported with --isolatedDeclarations. Add an explicit declaration for the properties assigned to this function.
 
     export class Foo {
         [o["prop.inner"]] ="A"
         ~~~~~~~~~~~~~~~~~
-!!! error TS1166: A computed property name in a class property declaration must have a simple literal type or a 'unique symbol' type.
-        ~~~~~~~~~~~~~~~~~
 !!! error TS9038: Computed property names on class or object literals cannot be inferred with --isolatedDeclarations.
         [o.prop.inner] = "B"
     }

tests/baselines/reference/isolatedDeclarationLazySymbols.types

@@ -40,8 +40,8 @@ const o = {
 foo[o["prop.inner"]] ="A";
 >foo[o["prop.inner"]] ="A" : "A"
 >                          : ^^^
->foo[o["prop.inner"]] : any
->                     : ^^^
+>foo[o["prop.inner"]] : string
+>                     : ^^^^^^
 >foo : typeof foo
 >    : ^^^^^^^^^^
 >o["prop.inner"] : "a"

tests/cases/compiler/computedPropertyWithEnumKey.ts

@@ -0,0 +1 @@
+enum Type { Foo = 'foo', '3x14' = '3.14' } type TypeMap = { [Type.Foo]: any; [Type['3x14']]: any; };