Merge pull request #483 from braxtonhall/fix-combine-with-all-errors

Fix combineWithAllErrors types

Author: supermacro

.changeset/thirty-grapes-drum.md

@@ -0,0 +1,5 @@
+---
+"neverthrow": patch
+---
+
+Fix `combineWithAllErrors` types

src/result-async.ts

@@ -278,22 +278,13 @@ type TraverseAsync<T, Depth extends number = 5> = IsLiteralArray<T> extends 1
   : never
 
 // This type is similar to the `TraverseAsync` while the errors are also
-// collected in order. For the checks/conditions made here, see that type
+// collected in a list. For the checks/conditions made here, see that type
 // for the documentation.
-type TraverseWithAllErrorsAsync<T, Depth extends number = 5> = IsLiteralArray<T> extends 1
-  ? Combine<T, Depth> extends [infer Oks, infer Errs]
-    ? ResultAsync<EmptyArrayToNever<Oks>, EmptyArrayToNever<Errs>>
-    : never
-  : Writable<T> extends Array<infer I>
-  ? Combine<MemberListOf<I>, Depth> extends [infer Oks, infer Errs]
-    ? Oks extends unknown[]
-      ? Errs extends unknown[]
-        ? ResultAsync<EmptyArrayToNever<Oks[number][]>, EmptyArrayToNever<Errs[number][]>>
-        : ResultAsync<EmptyArrayToNever<Oks[number][]>, Errs>
-      : Errs extends unknown[]
-      ? ResultAsync<Oks, EmptyArrayToNever<Errs[number][]>>
-      : ResultAsync<Oks, Errs>
-    : never
+type TraverseWithAllErrorsAsync<T, Depth extends number = 5> = TraverseAsync<
+  T,
+  Depth
+> extends ResultAsync<infer Oks, infer Errs>
+  ? ResultAsync<Oks, Errs[]>
   : never
 
 // Converts a reaodnly array into a writable array

src/result.ts

@@ -649,11 +649,11 @@ type Traverse<T, Depth extends number = 5> = Combine<T, Depth> extends [infer Ok
 
 // Traverses an array of results and returns a single result containing
 // the oks combined and the array of errors combined.
-type TraverseWithAllErrors<T, Depth extends number = 5> = Combine<T, Depth> extends [
+type TraverseWithAllErrors<T, Depth extends number = 5> = Traverse<T, Depth> extends Result<
   infer Oks,
-  infer Errs,
-]
-  ? Result<EmptyArrayToNever<Oks>, EmptyArrayToNever<Errs>>
+  infer Errs
+>
+  ? Result<Oks, Errs[]>
   : never
 
 // Combines the array of results into one result.

tests/index.test.ts

@@ -711,7 +711,7 @@ describe('Utils', () => {
           okAsync(true),
         ]
 
-        type ExpecteResult = Result<[ string, number, boolean ], [string, number, boolean]>
+        type ExpecteResult = Result<[ string, number, boolean ], (string | number | boolean)[]>
 
         const result: ExpecteResult = await ResultAsync.combineWithAllErrors(heterogenousList)
 

tests/typecheck-tests.ts

@@ -1177,7 +1177,7 @@ type CreateTuple<L, V = string> =
 
   (function describe(_ = 'combineWithAllErrors') {
     (function it(_ = 'combines different results into one') {
-      type Expectation = Result<[ number, string, never, never ], [never, never, string[], Error]>;
+      type Expectation = Result<[ number, string, never, never ], (string[] | Error)[]>;
 
       const result = Result.combineWithAllErrors([
         ok(1),
@@ -1191,7 +1191,7 @@ type CreateTuple<L, V = string> =
     });
 
     (function it(_ = 'combines only ok results into one') {
-      type Expectation = Result<[ number, string ], [never, never]>;
+      type Expectation = Result<[ number, string ], never[]>;
 
       const result = Result.combineWithAllErrors([
         ok(1),
@@ -1203,7 +1203,7 @@ type CreateTuple<L, V = string> =
     });
 
     (function it(_ = 'combines only err results into one') {
-      type Expectation = Result<[ never, never ], [number, 'string']>;
+      type Expectation = Result<[ never, never ], (number | 'string')[]>;
 
       const result = Result.combineWithAllErrors([
         err(1),
@@ -1224,10 +1224,20 @@ type CreateTuple<L, V = string> =
       const assignablefromCheck: typeof result = assignableToCheck;
     });
 
+    (function it(_ = 'combines arrays of different results to a result of an array') {
+      type Expectation = Result<(string | boolean)[], (number | string)[]>;
+      const results: (Result<string, number> | Result<boolean, string>)[] = [];
+
+      const result = Result.combineWithAllErrors(results);
+
+      const assignableToCheck: Expectation = result;
+      const assignablefromCheck: typeof result = assignableToCheck;
+    });
+
     (function describe(_ = 'inference on large tuples') {
       (function it(_ = 'Should correctly infer the type on tuples with 6 elements') {
         type Input = CreateTuple<6, Result<string, number>>
-        type Expectation = Result<CreateTuple<6, string>, CreateTuple<6, number>>
+        type Expectation = Result<CreateTuple<6, string>, number[]>
 
         const inputValues = input<Input>()
         const result = Result.combineWithAllErrors(inputValues)
@@ -1239,7 +1249,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 15 elements') {
         type Input = CreateTuple<15, Result<string, number>>
-        type Expectation = Result<CreateTuple<15, string>, CreateTuple<15, number>>
+        type Expectation = Result<CreateTuple<15, string>, number[]>
 
         const inputValues = input<Input>()
         const result = Result.combineWithAllErrors(inputValues)
@@ -1251,7 +1261,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 30 elements') {
         type Input = CreateTuple<30, Result<string, number>>
-        type Expectation = Result<CreateTuple<30, string>, CreateTuple<30, number>>
+        type Expectation = Result<CreateTuple<30, string>, number[]>
 
         const inputValues = input<Input>()
         const result = Result.combineWithAllErrors(inputValues)
@@ -1263,7 +1273,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 49 elements') {
         type Input = CreateTuple<49 , Result<string, number>>
-        type Expectation = Result<CreateTuple<49, string>, CreateTuple<49, number>>
+        type Expectation = Result<CreateTuple<49, string>, number[]>
 
         const inputValues = input<Input>()
         const result = Result.combineWithAllErrors(inputValues)
@@ -2199,7 +2209,7 @@ type CreateTuple<L, V = string> =
 
   (function describe(_ = 'combineWithAllErrors') {
     (function it(_ = 'combines different result asyncs into one') {
-      type Expectation = ResultAsync<[ number, string, never, never ], [never, never, string[], Error]>;
+      type Expectation = ResultAsync<[ number, string, never, never ], (string[] | Error)[]>;
 
       const result = ResultAsync.combineWithAllErrors([
         okAsync(1),
@@ -2213,7 +2223,7 @@ type CreateTuple<L, V = string> =
     });
 
     (function it(_ = 'combines only ok result asyncs into one') {
-      type Expectation = ResultAsync<[ number, string ], [never, never]>;
+      type Expectation = ResultAsync<[ number, string ], never[]>;
 
       const result = ResultAsync.combineWithAllErrors([
         okAsync(1),
@@ -2225,7 +2235,7 @@ type CreateTuple<L, V = string> =
     });
 
     (function it(_ = 'combines only err result asyncs into one') {
-      type Expectation = ResultAsync<[ never, never ], [number, string]>;
+      type Expectation = ResultAsync<[ never, never ], (number | string)[]>;
 
       const result = ResultAsync.combineWithAllErrors([
         errAsync(1),
@@ -2246,10 +2256,20 @@ type CreateTuple<L, V = string> =
       const assignablefromCheck: typeof result = assignableToCheck;
     });
 
+    (function it(_ = 'combines arrays of different result asyncs to a result of an array') {
+      type Expectation = ResultAsync<(string | boolean)[], (number | string)[]>;
+      const results: (ResultAsync<string, number> | ResultAsync<boolean, string>)[] = [];
+
+      const result = ResultAsync.combineWithAllErrors(results);
+
+      const assignableToCheck: Expectation = result;
+      const assignablefromCheck: typeof result = assignableToCheck;
+    });
+
     (function describe(_ = 'inference on large tuples') {
       (function it(_ = 'Should correctly infer the type on tuples with 6 elements') {
         type Input = CreateTuple<6, ResultAsync<string, number>>
-        type Expectation = ResultAsync<CreateTuple<6, string>, CreateTuple<6, number>>
+        type Expectation = ResultAsync<CreateTuple<6, string>, number[]>
 
         const inputValues = input<Input>()
         const result = ResultAsync.combineWithAllErrors(inputValues)
@@ -2261,7 +2281,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 15 elements') {
         type Input = CreateTuple<15, ResultAsync<string, number>>
-        type Expectation = ResultAsync<CreateTuple<15, string>, CreateTuple<15, number>>
+        type Expectation = ResultAsync<CreateTuple<15, string>, number[]>
 
         const inputValues = input<Input>()
         const result = ResultAsync.combineWithAllErrors(inputValues)
@@ -2273,7 +2293,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 30 elements') {
         type Input = CreateTuple<30, ResultAsync<string, number>>
-        type Expectation = ResultAsync<CreateTuple<30, string>, CreateTuple<30, number>>
+        type Expectation = ResultAsync<CreateTuple<30, string>, number[]>
 
         const inputValues = input<Input>()
         const result = ResultAsync.combineWithAllErrors(inputValues)
@@ -2285,7 +2305,7 @@ type CreateTuple<L, V = string> =
 
       (function it(_ = 'Should correctly infer the type on tuples with 49 elements') {
         type Input = CreateTuple<49 , ResultAsync<string, number>>
-        type Expectation = ResultAsync<CreateTuple<49, string>, CreateTuple<49, number>>
+        type Expectation = ResultAsync<CreateTuple<49, string>, number[]>
 
         const inputValues = input<Input>()
         const result = ResultAsync.combineWithAllErrors(inputValues)