From cdf454e747132153014856b4163bc7e7b9d3d362 Mon Sep 17 00:00:00 2001
From: sinclair <haydn.developer@gmail.com>
Date: Thu, 23 Nov 2023 14:35:05 +0900
Subject: [PATCH] Reimplement Index Types

---
 examples/index.ts      | 256 +++++++++++++----------------------------
 src/typebox.ts         |  34 ++----
 test/static/indexed.ts |   3 +
 3 files changed, 97 insertions(+), 196 deletions(-)

diff --git a/examples/index.ts b/examples/index.ts
index 8c7fdac6a..dbf625510 100644
--- a/examples/index.ts
+++ b/examples/index.ts
@@ -1,182 +1,92 @@
 import { TypeSystem } from '@sinclair/typebox/system'
 import { TypeCompiler } from '@sinclair/typebox/compiler'
 import { Value, ValuePointer } from '@sinclair/typebox/value'
-import {
-  Type,
-  Static,
-  TSchema,
-  TProperties,
-  TArray,
-  TLiteral,
-  TTemplateLiteral,
-  TypeGuard,
-  TemplateLiteralParser,
-  TemplateLiteralGenerator,
-  TemplateLiteralResolver,
-  TemplateLiteralFinite,
-  IsTemplateLiteralFiniteCheck,
-  KeyResolver,
-  TOptional,
-  UnionTypeIsOptional,
-} from '@sinclair/typebox'
+import { Type, Static, TSchema, TProperties, TArray, TLiteral, TTemplateLiteral, TypeGuard, TemplateLiteralParser, TOptional, UnionTypeIsOptional, TRecursive, TIntersect, TUnion, TTuple, TNever, TString, TNumber, UnionType, IntersectType } from '@sinclair/typebox'
 import { TObject } from '@sinclair/typebox'
 
-const A = Type.Intersect([Type.String(), Type.String()])
 
-const I = Type.Composite([
-  Type.Composite([Type.Object({ x: Type.String(), y: Type.Literal(1) }), Type.Object({ x: Type.String(), y: Type.Number() })]),
-  Type.Composite([Type.Object({ x: Type.Boolean(), y: Type.Number() }), Type.Object({ x: Type.String() })]),
-])
 
-const R = Type.Index(I, ['x'])
 
+// ------------------------------------------------------------------
+// TIndex
+// ------------------------------------------------------------------
 // prettier-ignore
-// export type UnionTypeIsOptional<T extends TSchema[]> =
-//   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-//     ? L extends TOptional<L>
-//       ? UnionTypeIsOptional<R>
-//       : false
-//     : true
-
-type X = UnionTypeIsOptional<[
-  TOptional<TNumber>,
-  TOptional<TNumber>,
-]>
-
-// // ------------------------------------------------------------------
-// // TIndex
-// // ------------------------------------------------------------------
-// // prettier-ignore
-// export type TIndexProperties<T extends TProperties, K extends PropertyKey> =
-//   K extends keyof T
-//     ? [T[K]]
-//     : []
-// // prettier-ignore
-// export type TIndexTuple<T extends TSchema[], K extends PropertyKey> =
-//   K extends keyof T
-//     ? [T[K]]
-//     : []
-// // prettier-ignore
-// export type TIndexArray<T extends TSchema, K extends PropertyKey> =
-//   K extends number
-//     ? [T]
-//     : []
-// // prettier-ignore
-// export type TIndexIntersect<T extends TSchema[], K extends PropertyKey> =
-//   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-//     ? [...TIndexKey<L, K>, ...TIndexIntersect<R, K>]
-//     : []
-// // prettier-ignore
-// export type TIndexUnionGather<T extends TSchema[], K extends PropertyKey> =
-//   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-//     ? [TIndexKey<L, K>, ...TIndexUnionGather<R, K>]
-//     : []
-// // prettier-ignore
-// export type TIndexUnionCheck<T extends TSchema[][]> =
-//   T extends [infer L extends TSchema[], ...infer R extends TSchema[][]]
-//     ? L extends []
-//       ? false
-//       : TIndexUnionCheck<R>
-//     : true
-// // prettier-ignore
-// export type TIndexUnionFinal<T extends TSchema[][]> =
-//   T extends [infer L extends TSchema[], ...infer R extends TSchema[][]]
-//     ? [...L, ...TIndexUnionFinal<R>]
-//     : []
-// // prettier-ignore
-// export type TIndexUnion<T extends TSchema[], K extends PropertyKey, G extends TSchema[][] = TIndexUnionGather<T, K>, C extends boolean = TIndexUnionCheck<G>> =
-//   C extends true
-//     ? TIndexUnionFinal<G>
-//     : []
-// // prettier-ignore
-// export type TIndexKey<T extends TSchema, K extends PropertyKey> =
-//   T extends TRecursive<infer S> ? TIndexKey<S, K> :
-//   T extends TIntersect<infer S> ? TIndexIntersect<S, K> :
-//   T extends TUnion<infer S> ? TIndexUnion<S, K> :
-//   T extends TTuple<infer S> ? TIndexTuple<S, K> :
-//   T extends TArray<infer S> ? TIndexArray<S, K> :
-//   T extends TObject<infer S> ? TIndexProperties<S, K> :
-//   []
-// // prettier-ignore
-// export type TIndexKeys<T extends TSchema, K extends PropertyKey[]> =
-//   K extends [infer L extends PropertyKey, ...infer R extends PropertyKey[]]
-//     ? [...TIndexKey<T, L>, ...TIndexKeys<T, R>]
-//     : []
-// export type TIndex<T extends TSchema, K extends PropertyKey[], R extends TSchema[] = TIndexKeys<T, K>> = UnionType<R>
-
-// export function Index<T extends TSchema, K extends string[]>(schema: T, keys: [...K]): TIndex<T, K>
-// export function Index<T extends TSchema, I extends TSchema, K extends PropertyKey[] = TKeyResolver<I>>(schema: T, keys: I): TIndex<T, K>
-// export function Index(schema: TSchema, keys: unknown): any {
-
-// }
-
-// import {} from '@sinclair/typebox'
-// // ------------------------------------------------------------------
-// // TIndexer
-// // ------------------------------------------------------------------
-// export type TKeyResolverTemplateLiteral<T extends TTemplateLiteral, F = IsTemplateLiteralFiniteCheck<T>> =
-//   F extends true
-//     ? UnionToTuple<Static<T>>
-//     : []
-// export type TKeyResolverUnion<T extends TSchema[]> =
-//   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-//     ? [...TKeyResolver<L>, ...TKeyResolverUnion<R>]
-//     : []
-// // prettier-ignore
-// export type TKeyResolver<T extends TSchema> =
-//   T extends TTemplateLiteral ? TKeyResolverTemplateLiteral<T> :
-//   T extends TUnion<infer S> ? TKeyResolverUnion<S> :
-//   T extends TLiteral<infer S> ? [S] :
-//   T extends TString ? [] :
-//   T extends TNumber ? [] :
-//   T extends TInteger ? [] :
-//   T extends TBigInt ? [] :
-//   []
-
-// const T = Type.TemplateLiteral('a${a|b}${string}')
-// const S = KeyResolver.ResolveKeys(T, { includePatterns: false })
-
-// console.log(S, 1)
-
-// console.log(S)
-
-// const E = Type.TemplateLiteral('a${string}')
-// type E = TKeyResolver<typeof E>
-
-// const R = TemplateLiteralResolver.Resolve(A)
-// console.log(R)
-
-// const S = Type.Intersect([
-//   Type.Object({ x: Type.Number() }),
-//   Type.Object({ y: Type.String() }),
-//   Type.Object({ z: Type.Boolean() })
-// ])
-
-// const T = Type.Object({
-//   x: Type.Object({
-//     y: Type.Object({
-//       i: Index(S, Type.TemplateLiteral('${x|a}'))
-//     })
-//   })
-// })
-
-// type T = Static<typeof T>
-
-// type A = TObject<{ x: TNumber }>
-// type B = TObject<{ x: TString }>
-// type C = TIntersect<[A, B]>
-// type X = TObject<{ x: TNumber }>
-// type Y = TObject<{ y: TString }>
-// type Z = TTuple<[X, Y]>
-
-// type T = TUnion<[C, Z]>
-
-// type S = TIndex<Z, [1]>
-
-// type Q = Array<{ x: 1 }>
-
-// type U = Q[number]
-
-export function Resolve(T: TObject<{}>, arg1: {}) {
-  throw new Error('Function not implemented.')
-}
+export type TIndexDiscardNever<T extends TSchema[]> =
+  T extends [infer L extends TSchema, ...infer R extends TSchema[]]
+    ? L extends TNever
+      ? [...TIndexDiscardNever<R>]
+      : [L, ...TIndexDiscardNever<R>]
+    : []
+export type TIndexProperty<T extends TProperties, K extends PropertyKey> = K extends keyof T ? T[K] : TNever
+export type TIndexTuple<T extends TSchema[], K extends PropertyKey> = K extends keyof T ? T[K] : TNever
+export type TIndexArray<T extends TSchema, K extends PropertyKey> = K extends number ? T : TNever
+// ------------------------------------------------------------------
+// TIndex: Intersect
+// ------------------------------------------------------------------
+export type TIndexIntersect<T extends TSchema[], K extends PropertyKey> =
+  T extends [infer L extends TSchema, ...infer R extends TSchema[]]
+    ? TIndexKey<L, K> extends infer N extends TSchema
+      ? N extends TNever
+        ? [...TIndexIntersect<R, K>]
+        : [N, ...TIndexIntersect<R, K>]
+      : []
+    : []
+// ------------------------------------------------------------------
+// TIndex: Union
+// ------------------------------------------------------------------
+// prettier-ignore
+export type TIndexUnionCollect<T extends TSchema[], K extends PropertyKey> =
+  T extends [infer L extends TSchema, ...infer R extends TSchema[]]
+    ? [TIndexKey<L, K>, ...TIndexUnionCollect<R, K>]
+    : []
+// prettier-ignore
+export type TIndexUnionCheck<T extends TSchema[][]> =
+  T extends [infer L extends TSchema[], ...infer R extends TSchema[][]]
+    ? L extends []
+      ? false
+      : TIndexUnionCheck<R>
+    : true
+// prettier-ignore
+export type TIndexUnion<
+  T extends TSchema[], K extends PropertyKey, 
+  G extends TSchema[] = TIndexUnionCollect<T, K>, 
+  C extends TSchema[] = TIndexDiscardNever<G>
+> = C
+// prettier-ignore
+export type TIndexKey<T extends TSchema, K extends PropertyKey> =
+  T extends TRecursive<infer S> ? TIndexKey<S, K> :
+  T extends TIntersect<infer S> ? IntersectType<TIndexIntersect<S, K>> :
+  T extends TUnion<infer S>     ? UnionType<TIndexUnion<S, K>> :
+  T extends TTuple<infer S>     ? TIndexTuple<S, K> :
+  T extends TArray<infer S>     ? TIndexArray<S, K> :
+  T extends TObject<infer S>    ? TIndexProperty<S, K> :
+  TNever
+// prettier-ignore
+export type TIndexKeys<T extends TSchema, K extends PropertyKey[]> =
+  K extends [infer L extends PropertyKey, ...infer R extends PropertyKey[]]
+    ? [TIndexKey<T, L>, ...TIndexKeys<T, R>]
+    : []
+
+export type TIndex<T extends TSchema, K extends PropertyKey[]> = UnionType<TIndexKeys<T, K>>
+
+type A = TUnion<[TObject<{
+    x: TString;
+    y: TLiteral<1>;
+}>, TObject<{
+    x: TNumber;
+    y: TNumber;
+}>]>
+
+type B = TIntersect<[TObject<{
+  x: TString;
+  y: TNumber;
+}>, TObject<{
+  x: TString;
+}>]>
+
+type I = TIntersect<[A, B]>
+
+// TIntersect<[TUnion<[TLiteral<1>, TNumber]>, TNumber]>
+type C = TIndex<I, ['y']>
+
+type S = Static<C>
\ No newline at end of file
diff --git a/src/typebox.ts b/src/typebox.ts
index be8309fb2..77c186f80 100644
--- a/src/typebox.ts
+++ b/src/typebox.ts
@@ -444,34 +444,22 @@ export type TKeyResolver<T extends TSchema> =
 // ------------------------------------------------------------------
 // TIndex
 // ------------------------------------------------------------------
-// prettier-ignore
-export type TIndexProperties<T extends TProperties, K extends PropertyKey> =
-  K extends keyof T
-    ? [T[K]]
-    : []
-// prettier-ignore
-export type TIndexTuple<T extends TSchema[], K extends PropertyKey> =
-  K extends keyof T
-    ? [T[K]]
-    : []
-// prettier-ignore
-export type TIndexArray<T extends TSchema, K extends PropertyKey> =
-  K extends number
-    ? [T]
-    : []
+export type TIndexProperties<T extends TProperties, K extends PropertyKey> = K extends keyof T ? [T[K]] : []
+export type TIndexTuple<T extends TSchema[], K extends PropertyKey> = K extends keyof T ? [T[K]] : []
+export type TIndexArray<T extends TSchema, K extends PropertyKey> = K extends number ? [T] : []
 // prettier-ignore
 export type TIndexIntersect<T extends TSchema[], K extends PropertyKey> =
   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-    ? L extends TUnion<infer U>
-      ? [TUnion<TIndexUnion<U, K>>, ...TIndexIntersect<R, K>]
+    ? L extends TIntersect<infer S extends TSchema[]> 
+      ? [IntersectType<TIndexIntersect<S, K>>, ...TIndexIntersect<R, K>] 
+      : L extends TUnion<infer S extends TSchema[]> 
+      ? [UnionType<TIndexUnion<S, K>>, ...TIndexIntersect<R, K>] 
       : [...TIndexKeyResolve<L, K>, ...TIndexIntersect<R, K>]
     : []
 // prettier-ignore
 export type TIndexUnionGather<T extends TSchema[], K extends PropertyKey> =
   T extends [infer L extends TSchema, ...infer R extends TSchema[]]
-    ? L extends TIntersect<infer U>
-      ? [TIntersect<TIndexIntersect<U, K>>, ...TIndexUnionGather<R, K>]
-      : [TIndexKeyResolve<L, K>, ...TIndexUnionGather<R, K>]
+    ? [TIndexKeyResolve<L, K>, ...TIndexUnionGather<R, K>]
     : []
 // prettier-ignore
 export type TIndexUnionCheck<T extends TSchema[][]> =
@@ -502,7 +490,7 @@ export type TIndexKeyResolve<T extends TSchema, K extends PropertyKey> =
 // prettier-ignore
 export type TIndexKey<T extends TSchema, K extends PropertyKey, R = TIndexKeyResolve<T, K>> = 
   R extends TSchema[] 
-    ? IntersectType<R> 
+    ? UnionType<R>
     : TNever
 // prettier-ignore
 export type TIndexKeysResolve<T extends TSchema, K extends PropertyKey[]> =
@@ -511,8 +499,8 @@ export type TIndexKeysResolve<T extends TSchema, K extends PropertyKey[]> =
     : []
 // prettier-ignore
 export type TIndexKeys<T extends TSchema, K extends PropertyKey[], R = TIndexKeysResolve<T, K>> = 
-  R extends TSchema[] 
-    ? UnionType<R> 
+  R extends TSchema[]
+    ? IntersectType<R> 
     : TNever
 export type TIndex<T extends TSchema, K extends PropertyKey[]> = TIndexKeys<T, K>
 // --------------------------------------------------------------------------
diff --git a/test/static/indexed.ts b/test/static/indexed.ts
index 419ef477a..31580c194 100644
--- a/test/static/indexed.ts
+++ b/test/static/indexed.ts
@@ -174,6 +174,9 @@ import { Type, Static } from '@sinclair/typebox'
   const D = Type.Object({ x: Type.String() })
   const I = Type.Intersect([Type.Intersect([A, B]), Type.Intersect([C, D])])
   const R = Type.Index(I, ['x', 'y'])
+
+  // TUnion<[TIntersect<[TIntersect<[TString, TNumber]>, TIntersect<[TString, TString]>]>, TIntersect<[TIntersect<[TLiteral<...>, TNumber]>, TNumber]>]>
+  // TUnion<[TUnion<[TString, TNumber, TString, TString]>, TUnion<[TLiteral<1>, TNumber, TNumber]>]>
   type O = Static<typeof R>
   Expect(R).ToStatic<1>()
 }