widen type, index signature, and add tests

Author: Arthur Ozga

src/compiler/checker.ts

@@ -84,6 +84,7 @@ namespace ts {
  getIndexTypeOfType,
  getBaseTypes,
  getBaseTypeOfLiteralType,
+ getWidenedType,
  getTypeFromTypeNode,
  getParameterType: getTypeAtPosition,
  getReturnTypeOfSignature,

src/compiler/diagnosticMessages.json

@@ -3311,7 +3311,7 @@
  "category": "Message",
  "code": 90016
  },
- "Add index accessor for missing property '{0}'": {
+ "Add index signature for missing property '{0}'": {
  "category": "Message",
  "code": 90017
  },

src/compiler/types.ts

@@ -2383,6 +2383,7 @@
  getIndexTypeOfType(type: Type, kind: IndexKind): Type;
  getBaseTypes(type: InterfaceType): BaseType[];
  getBaseTypeOfLiteralType(type: Type): Type;
+ getWidenedType(type: Type): Type;
  getReturnTypeOfSignature(signature: Signature): Type;
  /**
  * Gets the type of a parameter at a given position in a signature.

src/services/codefixes/fixAddMissingMember.ts

@@ -37,7 +37,7 @@ namespace ts.codefix {
  const binaryExpression = token.parent.parent as BinaryExpression;
 
  const checker = context.program.getTypeChecker();
- const widenedType = checker.getBaseTypeOfLiteralType(checker.getTypeAtLocation(binaryExpression.right));
+ const widenedType = checker.getWidenedType(checker.getBaseTypeOfLiteralType(checker.getTypeAtLocation(binaryExpression.right)));
  typeString = checker.typeToString(widenedType);
  }
 
@@ -54,7 +54,7 @@ namespace ts.codefix {
  }]
  },
  {
- description: formatStringFromArgs(getLocaleSpecificMessage(Diagnostics.Add_index_accessor_for_missing_property_0), [token.getText()]),
+ description: formatStringFromArgs(getLocaleSpecificMessage(Diagnostics.Add_index_signature_for_missing_property_0), [token.getText()]),
  changes: [{
  fileName: sourceFile.fileName,
  textChanges: [{

tests/cases/fourslash/codeFixUndeclaredIndexSignatureNumericLiteral.ts

@@ -0,0 +1,17 @@
+/// <reference path='fourslash.ts' />
+
+//// [|class A {
+//// constructor() {
+//// this.x = 10;
+//// }
+//// }|]
+
+verify.rangeAfterCodeFix(`
+class A {
+ [name: string]: number;
+
+ constructor() {
+ this.x = 10;
+ }
+}
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 1);

tests/cases/fourslash/codeFixUndeclaredPropertyFunctionEmptyClass.ts

@@ -0,0 +1,20 @@
+/// <reference path='fourslash.ts' />
+
+//// [|class A {
+//// constructor() {
+//// this.x = function(x: number, y?: A){
+//// return x > 0 ? x : y;
+//// }
+//// }
+//// }|]
+
+verify.rangeAfterCodeFix(`
+class A {
+ x: (x: number, y?: A) => A;
+ constructor() {
+ this.x = function(x: number, y?: A){
+ return x > 0 ? x : y;
+ }
+ }
+}
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);

tests/cases/fourslash/codeFixUndeclaredPropertyFunctionNonEmptyClass.ts

@@ -0,0 +1,22 @@
+/// <reference path='fourslash.ts' />
+
+//// [|class A {
+//// y: number;
+//// constructor(public a: number) {
+//// this.x = function(x: number, y?: A){
+//// return x > 0 ? x : y;
+//// }
+//// }
+//// }|]
+
+verify.rangeAfterCodeFix(`
+class A {
+ x: (x: number, y?: A) => number | A;
+ y: number;
+ constructor(public a: number) {
+ this.x = function(x: number, y?: A){
+ return x > 0 ? x : y;
+ }
+ }
+}
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);

tests/cases/fourslash/codeFixUndeclaredPropertyObjectLiteral.ts

@@ -2,16 +2,18 @@
 
 //// [|class A {
 //// constructor() {
-//// this.x = { a: 10, b: "hello" };
+//// let e: any = 10;
+//// this.x = { a: 10, b: "hello", c: undefined, d: null, e: e };
 //// }
 //// }|]
 
 verify.rangeAfterCodeFix(`
 class A {
- x: { a: number; b: string; };
+ x: { a: number; b: string; c: any; d: any; e: any; };
  
  constructor() {
- this.x = { a: 10, b: "hello" };
+ let e: any = 10;
+ this.x = { a: 10, b: "hello", c: undefined, d: null, e: e };
  }
 }
-`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);

tests/cases/fourslash/codeFixUndeclaredPropertyObjectLiteralStrictNullChecks.ts

@@ -0,0 +1,21 @@
+/// <reference path='fourslash.ts' />
+
+// @strictNullChecks: true
+
+//// [|class A {
+//// constructor() {
+//// let e: any = 10;
+//// this.x = { a: 10, b: "hello", c: undefined, d: null, e: e };
+//// }
+//// }|]
+
+verify.rangeAfterCodeFix(`
+class A {
+ x: { a: number; b: string; c: undefined; d: null; e: any; };
+ 
+ constructor() {
+ let e: any = 10;
+ this.x = { a: 10, b: "hello", c: undefined, d: null, e: e };
+ }
+}
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);

tests/cases/fourslash/codeFixUndeclaredPropertyThisType.ts

@@ -0,0 +1,17 @@
+/// <reference path='fourslash.ts' />
+
+//// [|class A {
+//// constructor() {
+//// this.mythis = this;
+//// }
+//// }|]
+
+verify.rangeAfterCodeFix(`
+class A {
+ mythis: this;
+
+ constructor() {
+ this.mythis = this;
+ }
+}
+`, /*includeWhiteSpace*/ false, /*errorCode*/ undefined, /*index*/ 0);