Merge pull request microsoft#25752 from Microsoft/objectsAgainstArrays

DanielRosenwasser · web-flow · commit 37277e86e602 · 2018-07-18T15:29:47.000-07:00
Avoid elaborating object literals against array-likes
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -11186,7 +11186,8 @@ namespace ts {
                 if (reportErrors) {
                     const bestMatchingType =
                         findMatchingDiscriminantType(source, target) ||
-                        findMatchingTypeReferenceOrTypeAliasReference(source, target);
+                        findMatchingTypeReferenceOrTypeAliasReference(source, target) ||
+                        findBestTypeForObjectLiteral(source, target);
 
                     isRelatedTo(source, bestMatchingType || targetTypes[targetTypes.length - 1], /*reportErrors*/ true);
                 }
@@ -11211,6 +11212,11 @@ namespace ts {
                 }
             }
 
+            function findBestTypeForObjectLiteral(source: Type, unionTarget: UnionOrIntersectionType) {
+                if (getObjectFlags(source) & ObjectFlags.ObjectLiteral && forEachType(unionTarget, isArrayLikeType)) {
+                    return find(unionTarget.types, t => !isArrayLikeType(t));
+                }
+            }
 
             // Keep this up-to-date with the same logic within `getApparentTypeOfContextualType`, since they should behave similarly
             function findMatchingDiscriminantType(source: Type, target: UnionOrIntersectionType) {
diff --git a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt
@@ -0,0 +1,30 @@
+tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts(9,5): error TS2322: Type '{ bar: { prop: number; }; }[]' is not assignable to type 'Foo[]'.
+  Type '{ bar: { prop: number; }; }' is not assignable to type 'Foo'.
+    Types of property 'bar' are incompatible.
+      Type '{ prop: number; }' is not assignable to type 'Bar | Bar[]'.
+        Type '{ prop: number; }' is not assignable to type 'Bar'.
+          Types of property 'prop' are incompatible.
+            Type 'number' is not assignable to type 'string'.
+
+
+==== tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts (1 errors) ====
+    interface Foo {
+      bar: Bar | Bar[];
+    }
+    
+    interface Bar {
+      prop: string;
+    }
+    
+    let x: Foo[] = [
+        ~
+!!! error TS2322: Type '{ bar: { prop: number; }; }[]' is not assignable to type 'Foo[]'.
+!!! error TS2322:   Type '{ bar: { prop: number; }; }' is not assignable to type 'Foo'.
+!!! error TS2322:     Types of property 'bar' are incompatible.
+!!! error TS2322:       Type '{ prop: number; }' is not assignable to type 'Bar | Bar[]'.
+!!! error TS2322:         Type '{ prop: number; }' is not assignable to type 'Bar'.
+!!! error TS2322:           Types of property 'prop' are incompatible.
+!!! error TS2322:             Type 'number' is not assignable to type 'string'.
+      { bar: { prop: 100 } }
+    ]
+    
diff --git a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.js b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.js
@@ -0,0 +1,18 @@
+//// [objectLiteralsAgainstUnionsOfArrays01.ts]
+interface Foo {
+  bar: Bar | Bar[];
+}
+
+interface Bar {
+  prop: string;
+}
+
+let x: Foo[] = [
+  { bar: { prop: 100 } }
+]
+
+
+//// [objectLiteralsAgainstUnionsOfArrays01.js]
+var x = [
+    { bar: { prop: 100 } }
+];
diff --git a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.symbols b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.symbols
@@ -0,0 +1,27 @@
+=== tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts ===
+interface Foo {
+>Foo : Symbol(Foo, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 0, 0))
+
+  bar: Bar | Bar[];
+>bar : Symbol(Foo.bar, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 0, 15))
+>Bar : Symbol(Bar, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 2, 1))
+>Bar : Symbol(Bar, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 2, 1))
+}
+
+interface Bar {
+>Bar : Symbol(Bar, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 2, 1))
+
+  prop: string;
+>prop : Symbol(Bar.prop, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 4, 15))
+}
+
+let x: Foo[] = [
+>x : Symbol(x, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 8, 3))
+>Foo : Symbol(Foo, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 0, 0))
+
+  { bar: { prop: 100 } }
+>bar : Symbol(bar, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 9, 3))
+>prop : Symbol(prop, Decl(objectLiteralsAgainstUnionsOfArrays01.ts, 9, 10))
+
+]
+
diff --git a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.types b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.types
@@ -0,0 +1,31 @@
+=== tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts ===
+interface Foo {
+>Foo : Foo
+
+  bar: Bar | Bar[];
+>bar : Bar | Bar[]
+>Bar : Bar
+>Bar : Bar
+}
+
+interface Bar {
+>Bar : Bar
+
+  prop: string;
+>prop : string
+}
+
+let x: Foo[] = [
+>x : Foo[]
+>Foo : Foo
+>[  { bar: { prop: 100 } }] : { bar: { prop: number; }; }[]
+
+  { bar: { prop: 100 } }
+>{ bar: { prop: 100 } } : { bar: { prop: number; }; }
+>bar : { prop: number; }
+>{ prop: 100 } : { prop: number; }
+>prop : number
+>100 : 100
+
+]
+
diff --git a/tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts b/tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts
@@ -0,0 +1,11 @@
+interface Foo {
+  bar: Bar | Bar[];
+}
+
+interface Bar {
+  prop: string;
+}
+
+let x: Foo[] = [
+  { bar: { prop: 100 } }
+]

Original file line number	Diff line number	Diff line change
`@@ -11186,7 +11186,8 @@ namespace ts {`
`11186`	`11186`	`if (reportErrors) {`
`11187`	`11187`	`const bestMatchingType =`
`11188`	`11188`	`findMatchingDiscriminantType(source, target) \|\|`
`11189`		`- findMatchingTypeReferenceOrTypeAliasReference(source, target);`
	`11189`	`+ findMatchingTypeReferenceOrTypeAliasReference(source, target) \|\|`
	`11190`	`+ findBestTypeForObjectLiteral(source, target);`
`11190`	`11191`
`11191`	`11192`	`isRelatedTo(source, bestMatchingType \|\| targetTypes[targetTypes.length - 1], /reportErrors/ true);`
`11192`	`11193`	`}`
`@@ -11211,6 +11212,11 @@ namespace ts {`
`11211`	`11212`	`}`
`11212`	`11213`	`}`
`11213`	`11214`
	`11215`	`+ function findBestTypeForObjectLiteral(source: Type, unionTarget: UnionOrIntersectionType) {`
	`11216`	`+ if (getObjectFlags(source) & ObjectFlags.ObjectLiteral && forEachType(unionTarget, isArrayLikeType)) {`
	`11217`	`+ return find(unionTarget.types, t => !isArrayLikeType(t));`
	`11218`	`+ }`
	`11219`	`+ }`
`11214`	`11220`
`11215`	`11221`	// Keep this up-to-date with the same logic within `getApparentTypeOfContextualType`, since they should behave similarly
`11216`	`11222`	`function findMatchingDiscriminantType(source: Type, target: UnionOrIntersectionType) {`