Contextually type this in object literals in JS

sandersn · sandersn · commit 08ae02263ae8 · 2017-07-17T15:59:18.000-07:00
Previously, `this` would only get a contextual type inside object
literals with `--noImplicitThis` turned on in Typescript files.
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -12602,7 +12602,7 @@ namespace ts {
                     }
                 }
             }
-            if (noImplicitThis) {
+            if (noImplicitThis || isInJavaScriptFile(func)) {
                 const containingLiteral = getContainingObjectLiteral(func);
                 if (containingLiteral) {
                     // We have an object literal method. Check if the containing object literal has a contextual type
diff --git a/tests/baselines/reference/contextualThisTypeInJavascript.symbols b/tests/baselines/reference/contextualThisTypeInJavascript.symbols
@@ -0,0 +1,25 @@
+=== tests/cases/conformance/types/thisType/context.js ===
+const obj = {
+>obj : Symbol(obj, Decl(context.js, 0, 5))
+
+    prop: 2,
+>prop : Symbol(prop, Decl(context.js, 0, 13))
+
+    method() {
+>method : Symbol(method, Decl(context.js, 1, 12))
+
+        this;
+>this : Symbol(obj, Decl(context.js, 0, 11))
+
+        this.prop;
+>this.prop : Symbol(prop, Decl(context.js, 0, 13))
+>this : Symbol(obj, Decl(context.js, 0, 11))
+>prop : Symbol(prop, Decl(context.js, 0, 13))
+
+        this.method;
+>this.method : Symbol(method, Decl(context.js, 1, 12))
+>this : Symbol(obj, Decl(context.js, 0, 11))
+>method : Symbol(method, Decl(context.js, 1, 12))
+    }
+}
+
diff --git a/tests/baselines/reference/contextualThisTypeInJavascript.types b/tests/baselines/reference/contextualThisTypeInJavascript.types
@@ -0,0 +1,27 @@
+=== tests/cases/conformance/types/thisType/context.js ===
+const obj = {
+>obj : { [x: string]: any; prop: number; method(): void; }
+>{    prop: 2,    method() {        this;        this.prop;        this.method;    }} : { [x: string]: any; prop: number; method(): void; }
+
+    prop: 2,
+>prop : number
+>2 : 2
+
+    method() {
+>method : () => void
+
+        this;
+>this : { [x: string]: any; prop: number; method(): void; }
+
+        this.prop;
+>this.prop : number
+>this : { [x: string]: any; prop: number; method(): void; }
+>prop : number
+
+        this.method;
+>this.method : () => void
+>this : { [x: string]: any; prop: number; method(): void; }
+>method : () => void
+    }
+}
+
diff --git a/tests/cases/conformance/types/thisType/contextualThisTypeInJavascript.ts b/tests/cases/conformance/types/thisType/contextualThisTypeInJavascript.ts
@@ -0,0 +1,12 @@
+// @allowJs: true
+// @checkJs: true
+// @noEmit: true
+// @Filename: context.js
+const obj = {
+    prop: 2,
+    method() {
+        this;
+        this.prop;
+        this.method;
+    }
+}

Original file line number	Diff line number	Diff line change
`@@ -12602,7 +12602,7 @@ namespace ts {`
`12602`	`12602`	`}`
`12603`	`12603`	`}`
`12604`	`12604`	`}`
`12605`		`- if (noImplicitThis) {`
	`12605`	`+ if (noImplicitThis \|\| isInJavaScriptFile(func)) {`
`12606`	`12606`	`const containingLiteral = getContainingObjectLiteral(func);`
`12607`	`12607`	`if (containingLiteral) {`
`12608`	`12608`	`// We have an object literal method. Check if the containing object literal has a contextual type`