Give mapped type properties a synthetic declaration name (microsoft#18023)

weswigham · web-flow · commit f824e7214ddd · 2017-08-24T16:48:11.000-07:00
* Escape symbol names which are not valid identifiers and wrap them in quotes

* Pass forward type, do work in getNameOfSymbol

* Minimal test

* Fix nit
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -3114,6 +3114,12 @@ namespace ts {
                         return "(Anonymous function)";
                 }
             }
+            if ((symbol as TransientSymbol).syntheticLiteralTypeOrigin) {
+                const stringValue = (symbol as TransientSymbol).syntheticLiteralTypeOrigin.value;
+                if (!isIdentifierText(stringValue, compilerOptions.target)) {
+                    return `"${escapeString(stringValue, CharacterCodes.doubleQuote)}"`;
+                }
+            }
             return unescapeLeadingUnderscores(symbol.escapedName);
         }
 
@@ -5724,7 +5730,14 @@ namespace ts {
             }
             setStructuredTypeMembers(type, members, emptyArray, emptyArray, stringIndexInfo, undefined);
 
-            function addMemberForKeyType(t: Type, propertySymbol?: Symbol) {
+            function addMemberForKeyType(t: Type, propertySymbolOrIndex?: Symbol | number) {
+                let propertySymbol: Symbol;
+                // forEachType delegates to forEach, which calls with a numeric second argument
+                //  the type system currently doesn't catch this incompatibility, so we annotate
+                //  the function ourselves to indicate the runtime behavior and deal with it here
+                if (typeof propertySymbolOrIndex === "object") {
+                    propertySymbol = propertySymbolOrIndex;
+                }
                 // Create a mapper from T to the current iteration type constituent. Then, if the
                 // mapped type is itself an instantiated type, combine the iteration mapper with the
                 // instantiation mapper.
@@ -5744,6 +5757,7 @@ namespace ts {
                         prop.syntheticOrigin = propertySymbol;
                         prop.declarations = propertySymbol.declarations;
                     }
+                    prop.syntheticLiteralTypeOrigin = t as StringLiteralType;
                     members.set(propName, prop);
                 }
                 else if (t.flags & TypeFlags.String) {
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
@@ -2972,6 +2972,7 @@ namespace ts {
         leftSpread?: Symbol;                // Left source for synthetic spread property
         rightSpread?: Symbol;               // Right source for synthetic spread property
         syntheticOrigin?: Symbol;           // For a property on a mapped or spread type, points back to the original property
+        syntheticLiteralTypeOrigin?: StringLiteralType; // For a property on a mapped type, indicates the type whose text to use as the declaration name, instead of the symbol name
         isDiscriminantProperty?: boolean;   // True if discriminant synthetic property
         resolvedExports?: SymbolTable;      // Resolved exports of module
         exportsChecked?: boolean;           // True if exports of external module have been checked
diff --git a/tests/baselines/reference/declarationQuotedMembers.js b/tests/baselines/reference/declarationQuotedMembers.js
@@ -0,0 +1,17 @@
+//// [declarationQuotedMembers.ts]
+export declare const mapped: { [K in 'a-b-c']: number }
+export const example = mapped;
+
+//// [declarationQuotedMembers.js]
+"use strict";
+exports.__esModule = true;
+exports.example = exports.mapped;
+
+
+//// [declarationQuotedMembers.d.ts]
+export declare const mapped: {
+    [K in 'a-b-c']: number;
+};
+export declare const example: {
+    "a-b-c": number;
+};
diff --git a/tests/baselines/reference/declarationQuotedMembers.symbols b/tests/baselines/reference/declarationQuotedMembers.symbols
@@ -0,0 +1,9 @@
+=== tests/cases/compiler/declarationQuotedMembers.ts ===
+export declare const mapped: { [K in 'a-b-c']: number }
+>mapped : Symbol(mapped, Decl(declarationQuotedMembers.ts, 0, 20))
+>K : Symbol(K, Decl(declarationQuotedMembers.ts, 0, 32))
+
+export const example = mapped;
+>example : Symbol(example, Decl(declarationQuotedMembers.ts, 1, 12))
+>mapped : Symbol(mapped, Decl(declarationQuotedMembers.ts, 0, 20))
+
diff --git a/tests/baselines/reference/declarationQuotedMembers.types b/tests/baselines/reference/declarationQuotedMembers.types
@@ -0,0 +1,9 @@
+=== tests/cases/compiler/declarationQuotedMembers.ts ===
+export declare const mapped: { [K in 'a-b-c']: number }
+>mapped : { a-b-c: number; }
+>K : K
+
+export const example = mapped;
+>example : { a-b-c: number; }
+>mapped : { a-b-c: number; }
+
diff --git a/tests/cases/compiler/declarationQuotedMembers.ts b/tests/cases/compiler/declarationQuotedMembers.ts
@@ -0,0 +1,3 @@
+// @declaration: true
+export declare const mapped: { [K in 'a-b-c']: number }
+export const example = mapped;

Original file line number	Diff line number	Diff line change
`@@ -3114,6 +3114,12 @@ namespace ts {`
`3114`	`3114`	`return "(Anonymous function)";`
`3115`	`3115`	`}`
`3116`	`3116`	`}`
	`3117`	`+ if ((symbol as TransientSymbol).syntheticLiteralTypeOrigin) {`
	`3118`	`+ const stringValue = (symbol as TransientSymbol).syntheticLiteralTypeOrigin.value;`
	`3119`	`+ if (!isIdentifierText(stringValue, compilerOptions.target)) {`
	`3120`	+ return `"${escapeString(stringValue, CharacterCodes.doubleQuote)}"`;
	`3121`	`+ }`
	`3122`	`+ }`
`3117`	`3123`	`return unescapeLeadingUnderscores(symbol.escapedName);`
`3118`	`3124`	`}`
`3119`	`3125`
`@@ -5724,7 +5730,14 @@ namespace ts {`
`5724`	`5730`	`}`
`5725`	`5731`	`setStructuredTypeMembers(type, members, emptyArray, emptyArray, stringIndexInfo, undefined);`
`5726`	`5732`
`5727`		`- function addMemberForKeyType(t: Type, propertySymbol?: Symbol) {`
	`5733`	`+ function addMemberForKeyType(t: Type, propertySymbolOrIndex?: Symbol \| number) {`
	`5734`	`+ let propertySymbol: Symbol;`
	`5735`	`+ // forEachType delegates to forEach, which calls with a numeric second argument`
	`5736`	`+ // the type system currently doesn't catch this incompatibility, so we annotate`
	`5737`	`+ // the function ourselves to indicate the runtime behavior and deal with it here`
	`5738`	`+ if (typeof propertySymbolOrIndex === "object") {`
	`5739`	`+ propertySymbol = propertySymbolOrIndex;`
	`5740`	`+ }`
`5728`	`5741`	`// Create a mapper from T to the current iteration type constituent. Then, if the`
`5729`	`5742`	`// mapped type is itself an instantiated type, combine the iteration mapper with the`
`5730`	`5743`	`// instantiation mapper.`
`@@ -5744,6 +5757,7 @@ namespace ts {`
`5744`	`5757`	`prop.syntheticOrigin = propertySymbol;`
`5745`	`5758`	`prop.declarations = propertySymbol.declarations;`
`5746`	`5759`	`}`
	`5760`	`+ prop.syntheticLiteralTypeOrigin = t as StringLiteralType;`
`5747`	`5761`	`members.set(propName, prop);`
`5748`	`5762`	`}`
`5749`	`5763`	`else if (t.flags & TypeFlags.String) {`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+// @declaration: true`
	`2`	`+export declare const mapped: { [K in 'a-b-c']: number }`
	`3`	`+export const example = mapped;`