Dedupes for min/max (#1297)

packages/util/src/bi/index.ts

@@ -9,7 +9,6 @@ export * from './consts';
 
 export { nSqrt } from './sqrt';
 export { nToBigInt } from './toBigInt';
-export { nMax } from './max';
-export { nMin } from './min';
+export { nMax, nMin } from './min';
 export { nToHex } from './toHex';
 export { nToU8a } from './toU8a';

packages/util/src/bi/max.ts

@@ -1,22 +0,0 @@
-// Copyright 2017-2021 @polkadot/util authors & contributors
-// SPDX-License-Identifier: Apache-2.0
-
-import { assert } from '../assert';
-
-/**
- * @name nMax
- * @summary Finds and returns the highest value in an array of bigint.
- */
-export function nMax (...items: bigint[]): bigint {
-  assert(items.length >= 1, 'Must provide one or more bigint arguments');
-
-  let result = items[0];
-
-  for (let i = 1; i < items.length; i++) {
-    if (items[i] > result) {
-      result = items[i];
-    }
-  }
-
-  return result;
-}

packages/util/src/bi/min.ts

@@ -3,20 +3,40 @@
 
 import { assert } from '../assert';
 
-/**
- * @name nMin
- * @summary Finds and returns the lowest value in an array of bigint.
- */
-export function nMin (...items: bigint[]): bigint {
+function gt (a: bigint, b: bigint): boolean {
+  return a > b;
+}
+
+function lt (a: bigint, b: bigint): boolean {
+  return a < b;
+}
+
+function find (items: bigint[], cmp: (a: bigint, b: bigint) => boolean): bigint {
   assert(items.length >= 1, 'Must provide one or more bigint arguments');
 
   let result = items[0];
 
   for (let i = 1; i < items.length; i++) {
-    if (items[i] < result) {
+    if (cmp(items[i], result)) {
       result = items[i];
     }
   }
 
   return result;
 }
+
+/**
+ * @name nMax
+ * @summary Finds and returns the highest value in an array of bigint.
+ */
+export function nMax (...items: bigint[]): bigint {
+  return find(items, gt);
+}
+
+/**
+ * @name nMin
+ * @summary Finds and returns the lowest value in an array of bigint.
+ */
+export function nMin (...items: bigint[]): bigint {
+  return find(items, lt);
+}

packages/util/src/bn/index.ts

@@ -9,8 +9,7 @@ export * from './consts';
 
 export { BN } from './bn';
 export { bnFromHex } from './fromHex';
-export { bnMax } from './max';
-export { bnMin } from './min';
+export { bnMax, bnMin } from './min';
 export { bnSqrt } from './sqrt';
 export { bnToBn } from './toBn';
 export { bnToHex } from './toHex';

packages/util/src/bn/max.ts

@@ -1,34 +0,0 @@
-// Copyright 2017-2021 @polkadot/util authors & contributors
-// SPDX-License-Identifier: Apache-2.0
-
-import { assert } from '../assert';
-import { BN } from './bn';
-
-export function checkMaxMin (type: 'max' | 'min', items: BN[]): BN {
-  assert(items.length >= 1, 'Must provide one or more BN arguments');
-
-  let result = items[0];
-
-  for (let i = 1; i < items.length; i++) {
-    result = BN[type](result, items[i]);
-  }
-
-  return result;
-}
-
-/**
- * @name bnMax
- * @summary Finds and returns the highest value in an array of BNs.
- * @example
- * <BR>
- *
- * ```javascript
- * import BN from 'bn.js';
- * import { bnMax } from '@polkadot/util';
- *
- * bnMax([new BN(1), new BN(3), new BN(2)]).toString(); // => '3'
- * ```
- */
-export function bnMax (...items: BN[]): BN {
-  return checkMaxMin('max', items);
-}

packages/util/src/bn/min.ts

@@ -1,9 +1,37 @@
 // Copyright 2017-2021 @polkadot/util authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { BN } from './bn';
+import { assert } from '../assert';
+import { BN } from './bn';
 
-import { checkMaxMin } from './max';
+export function find (items: BN[], cmp: (a: BN, b: BN) => BN): BN {
+  assert(items.length >= 1, 'Must provide one or more BN arguments');
+
+  let result = items[0];
+
+  for (let i = 1; i < items.length; i++) {
+    result = cmp(result, items[i]);
+  }
+
+  return result;
+}
+
+/**
+ * @name bnMax
+ * @summary Finds and returns the highest value in an array of BNs.
+ * @example
+ * <BR>
+ *
+ * ```javascript
+ * import BN from 'bn.js';
+ * import { bnMax } from '@polkadot/util';
+ *
+ * bnMax([new BN(1), new BN(3), new BN(2)]).toString(); // => '3'
+ * ```
+ */
+export function bnMax (...items: BN[]): BN {
+  return find(items, BN.max);
+}
 
 /**
  * @name bnMin
@@ -19,5 +47,5 @@ import { checkMaxMin } from './max';
  * ```
  */
 export function bnMin (...items: BN[]): BN {
-  return checkMaxMin('min', items);
+  return find(items, BN.min);
 }