feat: use varargs types instead of overloads

andnp · Mar 11, 2019 · a2c1162 · a2c1162
1 parent 9d2e009
commit a2c1162
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Showing 2 changed files with 3 additions and 19 deletions.
diff --git a/src/types/functions.ts b/src/types/functions.ts
@@ -22,28 +22,12 @@ export type AnyFunc<R = any> = (...args: any[]) => R;
  * @returns the function `F` with new return value `R`
  */
 export type OverwriteReturn<F extends AnyFunc, R> =
-    F extends () => any ? () => R :
-    F extends (x1: infer X1) => any ? (x1: X1) => R :
-    F extends (x1: infer X1, x2: infer X2) => any ? (x1: X1, x2: X2) => R :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3) => any ? (x1: X1, x2: X2, x3: X3) => R :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4) => any ? (x1: X1, x2: X2, x3: X3, x4: X4) => R :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5) => any ? (x1: X1, x2: X2, x3: X3, x4: X4, x5: X5) => R :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5, x6: infer X6) => any ? (x1: X1, x2: X2, x3: X3, x4: X4, x5: X5, x6: X6) => R :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5, x6: infer X6, x7: infer X7) => any ? (x1: X1, x2: X2, x3: X3, x4: X4, x5: X5, x6: X6, x7: X7) => R :
-        AnyFunc<R>;
+    F extends ((...x: infer T) => unknown) ? ((...x: T) => R) : AnyFunc<R>;
 
 /**
  * Returns a tuple type of a functions arguments up to 7.
  * @param F a function with up to 7 arguments
  * @returns a tuple containing `F`'s argument types
  */
 export type ArgsAsTuple<F extends AnyFunc> =
-    F extends () => any ? void[] :
-    F extends (x1: infer X1) => any ? [X1] :
-    F extends (x1: infer X1, x2: infer X2) => any ? [X1, X2] :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3) => any ? [X1, X2, X3] :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4) => any ? [X1, X2, X3, X4] :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5) => any ? [X1, X2, X3, X4, X5] :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5, x6: infer X6) => any ? [X1, X2, X3, X4, X5, X6] :
-    F extends (x1: infer X1, x2: infer X2, x3: infer X3, x4: infer X4, x5: infer X5, x6: infer X6, x7: infer X7) => any ? [X1, X2, X3, X4, X5, X6, X7] :
-        any[];
+    F extends ((...x: infer T) => unknown) ? T : any[];
diff --git a/test/functions/ArgsAsTuple.test.ts b/test/functions/ArgsAsTuple.test.ts
@@ -9,7 +9,7 @@ test("Can get a tuple of function's argument types", t => {
     type F2 = (x: number, y: string) => any;
     type F3 = (x: number, y: string, z: boolean) => any;
 
-    type E0 = void[];
+    type E0 = [];
     type E1 = [number];
     type E2 = [number, string];
     type E3 = [number, string, boolean];