add extra test case

Author: Andarist

src/compiler/checker.ts

@@ -27162,7 +27162,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
         function inferToConditionalType(source: Type, target: ConditionalType) {
             const info = target.root.isDistributive ? getInferenceInfoForType(getActualTypeVariable(target.checkType)) : undefined;
-            const saveIndividualPriority = info?.individualPriority
+            const saveIndividualPriority = info?.individualPriority;
             if (info) {
                 info.individualPriority = (info.individualPriority || InferencePriority.None) | InferencePriority.DistributiveConditional;
             }

tests/baselines/reference/inferToDistributiveConditionalType1.symbols

@@ -0,0 +1,38 @@
+//// [tests/cases/compiler/inferToDistributiveConditionalType1.ts] ////
+
+=== inferToDistributiveConditionalType1.ts ===
+declare class Animal { eat(): void; }
+>Animal : Symbol(Animal, Decl(inferToDistributiveConditionalType1.ts, 0, 0))
+>eat : Symbol(Animal.eat, Decl(inferToDistributiveConditionalType1.ts, 0, 22))
+
+declare class Cat extends Animal { meow(): void; }
+>Cat : Symbol(Cat, Decl(inferToDistributiveConditionalType1.ts, 0, 37))
+>Animal : Symbol(Animal, Decl(inferToDistributiveConditionalType1.ts, 0, 0))
+>meow : Symbol(Cat.meow, Decl(inferToDistributiveConditionalType1.ts, 1, 34))
+
+declare class Dog extends Animal { bark(): void; }
+>Dog : Symbol(Dog, Decl(inferToDistributiveConditionalType1.ts, 1, 50))
+>Animal : Symbol(Animal, Decl(inferToDistributiveConditionalType1.ts, 0, 0))
+>bark : Symbol(Dog.bark, Decl(inferToDistributiveConditionalType1.ts, 2, 34))
+
+declare function test1<T>(a: T extends unknown ? { prop: T } : never): T;
+>test1 : Symbol(test1, Decl(inferToDistributiveConditionalType1.ts, 2, 50))
+>T : Symbol(T, Decl(inferToDistributiveConditionalType1.ts, 4, 23))
+>a : Symbol(a, Decl(inferToDistributiveConditionalType1.ts, 4, 26))
+>T : Symbol(T, Decl(inferToDistributiveConditionalType1.ts, 4, 23))
+>prop : Symbol(prop, Decl(inferToDistributiveConditionalType1.ts, 4, 50))
+>T : Symbol(T, Decl(inferToDistributiveConditionalType1.ts, 4, 23))
+>T : Symbol(T, Decl(inferToDistributiveConditionalType1.ts, 4, 23))
+
+declare const arg1: { prop: Dog } | { prop: Cat };
+>arg1 : Symbol(arg1, Decl(inferToDistributiveConditionalType1.ts, 5, 13))
+>prop : Symbol(prop, Decl(inferToDistributiveConditionalType1.ts, 5, 21))
+>Dog : Symbol(Dog, Decl(inferToDistributiveConditionalType1.ts, 1, 50))
+>prop : Symbol(prop, Decl(inferToDistributiveConditionalType1.ts, 5, 37))
+>Cat : Symbol(Cat, Decl(inferToDistributiveConditionalType1.ts, 0, 37))
+
+const result1 = test1(arg1);
+>result1 : Symbol(result1, Decl(inferToDistributiveConditionalType1.ts, 6, 5))
+>test1 : Symbol(test1, Decl(inferToDistributiveConditionalType1.ts, 2, 50))
+>arg1 : Symbol(arg1, Decl(inferToDistributiveConditionalType1.ts, 5, 13))
+

tests/baselines/reference/inferToDistributiveConditionalType1.types

@@ -0,0 +1,51 @@
+//// [tests/cases/compiler/inferToDistributiveConditionalType1.ts] ////
+
+=== inferToDistributiveConditionalType1.ts ===
+declare class Animal { eat(): void; }
+>Animal : Animal
+>       : ^^^^^^
+>eat : () => void
+>    : ^^^^^^    
+
+declare class Cat extends Animal { meow(): void; }
+>Cat : Cat
+>    : ^^^
+>Animal : Animal
+>       : ^^^^^^
+>meow : () => void
+>     : ^^^^^^    
+
+declare class Dog extends Animal { bark(): void; }
+>Dog : Dog
+>    : ^^^
+>Animal : Animal
+>       : ^^^^^^
+>bark : () => void
+>     : ^^^^^^    
+
+declare function test1<T>(a: T extends unknown ? { prop: T } : never): T;
+>test1 : <T>(a: T extends unknown ? { prop: T; } : never) => T
+>      : ^ ^^ ^^                                        ^^^^^ 
+>a : T extends unknown ? { prop: T; } : never
+>  : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^
+>prop : T
+>     : ^
+
+declare const arg1: { prop: Dog } | { prop: Cat };
+>arg1 : { prop: Dog; } | { prop: Cat; }
+>     : ^^^^^^^^   ^^^^^^^^^^^^^^   ^^^
+>prop : Dog
+>     : ^^^
+>prop : Cat
+>     : ^^^
+
+const result1 = test1(arg1);
+>result1 : Cat | Dog
+>        : ^^^^^^^^^
+>test1(arg1) : Cat | Dog
+>            : ^^^^^^^^^
+>test1 : <T>(a: T extends unknown ? { prop: T; } : never) => T
+>      : ^ ^^ ^^                                        ^^^^^ 
+>arg1 : { prop: Dog; } | { prop: Cat; }
+>     : ^^^^^^^^   ^^^^^^^^^^^^^^   ^^^
+

tests/cases/compiler/inferToDistributiveConditionalType1.ts

@@ -0,0 +1,10 @@
+// @strict: true
+// @noEmit: true
+
+declare class Animal { eat(): void; }
+declare class Cat extends Animal { meow(): void; }
+declare class Dog extends Animal { bark(): void; }
+
+declare function test1<T>(a: T extends unknown ? { prop: T } : never): T;
+declare const arg1: { prop: Dog } | { prop: Cat };
+const result1 = test1(arg1);