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AndaristAndarist
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Infer into recursive mapped type targets (#53647)
1 parent a05699c commit bd61cbb

6 files changed

+195
-19
lines changed

‎src/compiler/checker.ts

Lines changed: 10 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -2068,7 +2068,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
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/** Key is "/path/to/a.ts|/path/to/b.ts". */
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var amalgamatedDuplicates: Map<string, DuplicateInfoForFiles> | undefined;
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var reverseMappedCache = new Map<string, Type | undefined>();
2071-
var inInferTypeForHomomorphicMappedType = false;
2071+
var homomorphicMappedTypeInferenceStack: string[] = [];
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var ambientModulesCache: Symbol[] | undefined;
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/**
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* List of every ambient module with a "*" wildcard.
@@ -24126,17 +24126,18 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
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* variable T[P] (i.e. we treat the type T[P] as the type variable we're inferring for).
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*/
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function inferTypeForHomomorphicMappedType(source: Type, target: MappedType, constraint: IndexType): Type | undefined {
24129-
if (inInferTypeForHomomorphicMappedType) {
24130-
return undefined;
24129+
const cacheKey = source.id + "," + target.id + "," + constraint.id;
24130+
if (reverseMappedCache.has(cacheKey)) {
24131+
return reverseMappedCache.get(cacheKey);
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}
24132-
const key = source.id + "," + target.id + "," + constraint.id;
24133-
if (reverseMappedCache.has(key)) {
24134-
return reverseMappedCache.get(key);
24133+
const recursionKey = source.id + "," + (target.target || target).id;
24134+
if (contains(homomorphicMappedTypeInferenceStack, recursionKey)) {
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return undefined;
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}
24136-
inInferTypeForHomomorphicMappedType = true;
24137+
homomorphicMappedTypeInferenceStack.push(recursionKey);
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const type = createReverseMappedType(source, target, constraint);
24138-
inInferTypeForHomomorphicMappedType = false;
24139-
reverseMappedCache.set(key, type);
24139+
homomorphicMappedTypeInferenceStack.pop();
24140+
reverseMappedCache.set(cacheKey, type);
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return type;
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}
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‎tests/baselines/reference/mappedTypeRecursiveInference.errors.txt

Lines changed: 20 additions & 6 deletions
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‎tests/baselines/reference/mappedTypeRecursiveInference.types

Lines changed: 4 additions & 4 deletions
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‎tests/baselines/reference/mappedTypeRecursiveInference2.symbols

Lines changed: 73 additions & 0 deletions
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@@ -0,0 +1,73 @@
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//// [tests/cases/compiler/mappedTypeRecursiveInference2.ts] ////
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=== mappedTypeRecursiveInference2.ts ===
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type MorphTuple = [string, "|>", any]
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>MorphTuple : Symbol(MorphTuple, Decl(mappedTypeRecursiveInference2.ts, 0, 0))
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type validateMorph<def extends MorphTuple> = def[1] extends "|>"
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>validateMorph : Symbol(validateMorph, Decl(mappedTypeRecursiveInference2.ts, 0, 37))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 2, 19))
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>MorphTuple : Symbol(MorphTuple, Decl(mappedTypeRecursiveInference2.ts, 0, 0))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 2, 19))
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? [validateDefinition<def[0]>, "|>", (In: def[0]) => unknown]
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>validateDefinition : Symbol(validateDefinition, Decl(mappedTypeRecursiveInference2.ts, 4, 9))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 2, 19))
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>In : Symbol(In, Decl(mappedTypeRecursiveInference2.ts, 3, 42))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 2, 19))
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: def
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 2, 19))
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type validateDefinition<def> = def extends MorphTuple
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>validateDefinition : Symbol(validateDefinition, Decl(mappedTypeRecursiveInference2.ts, 4, 9))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 6, 24))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 6, 24))
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>MorphTuple : Symbol(MorphTuple, Decl(mappedTypeRecursiveInference2.ts, 0, 0))
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? validateMorph<def>
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>validateMorph : Symbol(validateMorph, Decl(mappedTypeRecursiveInference2.ts, 0, 37))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 6, 24))
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: {
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[k in keyof def]: validateDefinition<def[k]>
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>k : Symbol(k, Decl(mappedTypeRecursiveInference2.ts, 9, 11))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 6, 24))
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>validateDefinition : Symbol(validateDefinition, Decl(mappedTypeRecursiveInference2.ts, 4, 9))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 6, 24))
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>k : Symbol(k, Decl(mappedTypeRecursiveInference2.ts, 9, 11))
39+
}
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declare function type<def>(def: validateDefinition<def>): def
42+
>type : Symbol(type, Decl(mappedTypeRecursiveInference2.ts, 10, 7))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 12, 22), Decl(mappedTypeRecursiveInference2.ts, 12, 27))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 12, 22), Decl(mappedTypeRecursiveInference2.ts, 12, 27))
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>validateDefinition : Symbol(validateDefinition, Decl(mappedTypeRecursiveInference2.ts, 4, 9))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 12, 22), Decl(mappedTypeRecursiveInference2.ts, 12, 27))
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>def : Symbol(def, Decl(mappedTypeRecursiveInference2.ts, 12, 22), Decl(mappedTypeRecursiveInference2.ts, 12, 27))
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const shallow = type(["ark", "|>", (x) => x.length])
50+
>shallow : Symbol(shallow, Decl(mappedTypeRecursiveInference2.ts, 14, 5))
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>type : Symbol(type, Decl(mappedTypeRecursiveInference2.ts, 10, 7))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 14, 36))
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>x.length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 14, 36))
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>length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
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const objectLiteral = type({ a: ["ark", "|>", (x) => x.length] })
58+
>objectLiteral : Symbol(objectLiteral, Decl(mappedTypeRecursiveInference2.ts, 15, 5))
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>type : Symbol(type, Decl(mappedTypeRecursiveInference2.ts, 10, 7))
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>a : Symbol(a, Decl(mappedTypeRecursiveInference2.ts, 15, 28))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 15, 47))
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>x.length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 15, 47))
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>length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
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66+
const nestedTuple = type([["ark", "|>", (x) => x.length]])
67+
>nestedTuple : Symbol(nestedTuple, Decl(mappedTypeRecursiveInference2.ts, 16, 5))
68+
>type : Symbol(type, Decl(mappedTypeRecursiveInference2.ts, 10, 7))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 16, 41))
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>x.length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
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>x : Symbol(x, Decl(mappedTypeRecursiveInference2.ts, 16, 41))
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>length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
73+

‎tests/baselines/reference/mappedTypeRecursiveInference2.types

Lines changed: 68 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,68 @@
1+
//// [tests/cases/compiler/mappedTypeRecursiveInference2.ts] ////
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3+
=== mappedTypeRecursiveInference2.ts ===
4+
type MorphTuple = [string, "|>", any]
5+
>MorphTuple : [string, "|>", any]
6+
7+
type validateMorph<def extends MorphTuple> = def[1] extends "|>"
8+
>validateMorph : validateMorph<def>
9+
10+
? [validateDefinition<def[0]>, "|>", (In: def[0]) => unknown]
11+
>In : def[0]
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13+
: def
14+
15+
type validateDefinition<def> = def extends MorphTuple
16+
>validateDefinition : validateDefinition<def>
17+
18+
? validateMorph<def>
19+
: {
20+
[k in keyof def]: validateDefinition<def[k]>
21+
}
22+
23+
declare function type<def>(def: validateDefinition<def>): def
24+
>type : <def>(def: validateDefinition<def>) => def
25+
>def : validateDefinition<def>
26+
27+
const shallow = type(["ark", "|>", (x) => x.length])
28+
>shallow : ["ark", "|>", (x: "ark") => number]
29+
>type(["ark", "|>", (x) => x.length]) : ["ark", "|>", (x: "ark") => number]
30+
>type : <def>(def: validateDefinition<def>) => def
31+
>["ark", "|>", (x) => x.length] : ["ark", "|>", (x: "ark") => number]
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>"ark" : "ark"
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>"|>" : "|>"
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>(x) => x.length : (x: "ark") => number
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>x : "ark"
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>x.length : number
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>x : "ark"
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>length : number
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const objectLiteral = type({ a: ["ark", "|>", (x) => x.length] })
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>objectLiteral : { a: ["ark", "|>", (x: "ark") => number]; }
42+
>type({ a: ["ark", "|>", (x) => x.length] }) : { a: ["ark", "|>", (x: "ark") => number]; }
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>type : <def>(def: validateDefinition<def>) => def
44+
>{ a: ["ark", "|>", (x) => x.length] } : { a: ["ark", "|>", (x: "ark") => number]; }
45+
>a : ["ark", "|>", (x: "ark") => number]
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>["ark", "|>", (x) => x.length] : ["ark", "|>", (x: "ark") => number]
47+
>"ark" : "ark"
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>"|>" : "|>"
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>(x) => x.length : (x: "ark") => number
50+
>x : "ark"
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>x.length : number
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>x : "ark"
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>length : number
54+
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const nestedTuple = type([["ark", "|>", (x) => x.length]])
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>nestedTuple : [["ark", "|>", (x: "ark") => number]]
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>type([["ark", "|>", (x) => x.length]]) : [["ark", "|>", (x: "ark") => number]]
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>type : <def>(def: validateDefinition<def>) => def
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>[["ark", "|>", (x) => x.length]] : [["ark", "|>", (x: "ark") => number]]
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>["ark", "|>", (x) => x.length] : ["ark", "|>", (x: "ark") => number]
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>"ark" : "ark"
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>"|>" : "|>"
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>(x) => x.length : (x: "ark") => number
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>x : "ark"
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>x.length : number
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>x : "ark"
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>length : number
68+

‎tests/cases/compiler/mappedTypeRecursiveInference2.ts

Lines changed: 20 additions & 0 deletions
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// @strict: true
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// @noEmit: true
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type MorphTuple = [string, "|>", any]
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6+
type validateMorph<def extends MorphTuple> = def[1] extends "|>"
7+
? [validateDefinition<def[0]>, "|>", (In: def[0]) => unknown]
8+
: def
9+
10+
type validateDefinition<def> = def extends MorphTuple
11+
? validateMorph<def>
12+
: {
13+
[k in keyof def]: validateDefinition<def[k]>
14+
}
15+
16+
declare function type<def>(def: validateDefinition<def>): def
17+
18+
const shallow = type(["ark", "|>", (x) => x.length])
19+
const objectLiteral = type({ a: ["ark", "|>", (x) => x.length] })
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const nestedTuple = type([["ark", "|>", (x) => x.length]])

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