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node_modules/fast-check/lib/esm/arbitrary/_internals/SubarrayArbitrary.js

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+import { Arbitrary } from '../../check/arbitrary/definition/Arbitrary.js';
+import { Value } from '../../check/arbitrary/definition/Value.js';
+import { makeLazy } from '../../stream/LazyIterableIterator.js';
+import { Stream } from '../../stream/Stream.js';
+import { safeMap, safePush, safeSlice, safeSort, safeSplice } from '../../utils/globals.js';
+import { isSubarrayOf } from './helpers/IsSubarrayOf.js';
+import { IntegerArbitrary } from './IntegerArbitrary.js';
+const safeMathFloor = Math.floor;
+const safeMathLog = Math.log;
+const safeArrayIsArray = Array.isArray;
+export class SubarrayArbitrary extends Arbitrary {
+    constructor(originalArray, isOrdered, minLength, maxLength) {
+        super();
+        this.originalArray = originalArray;
+        this.isOrdered = isOrdered;
+        this.minLength = minLength;
+        this.maxLength = maxLength;
+        if (minLength < 0 || minLength > originalArray.length)
+            throw new Error('fc.*{s|S}ubarrayOf expects the minimal length to be between 0 and the size of the original array');
+        if (maxLength < 0 || maxLength > originalArray.length)
+            throw new Error('fc.*{s|S}ubarrayOf expects the maximal length to be between 0 and the size of the original array');
+        if (minLength > maxLength)
+            throw new Error('fc.*{s|S}ubarrayOf expects the minimal length to be inferior or equal to the maximal length');
+        this.lengthArb = new IntegerArbitrary(minLength, maxLength);
+        this.biasedLengthArb =
+            minLength !== maxLength
+                ? new IntegerArbitrary(minLength, minLength + safeMathFloor(safeMathLog(maxLength - minLength) / safeMathLog(2)))
+                : this.lengthArb;
+    }
+    generate(mrng, biasFactor) {
+        const lengthArb = biasFactor !== undefined && mrng.nextInt(1, biasFactor) === 1 ? this.biasedLengthArb : this.lengthArb;
+        const size = lengthArb.generate(mrng, undefined);
+        const sizeValue = size.value;
+        const remainingElements = safeMap(this.originalArray, (_v, idx) => idx);
+        const ids = [];
+        for (let index = 0; index !== sizeValue; ++index) {
+            const selectedIdIndex = mrng.nextInt(0, remainingElements.length - 1);
+            safePush(ids, remainingElements[selectedIdIndex]);
+            safeSplice(remainingElements, selectedIdIndex, 1);
+        }
+        if (this.isOrdered) {
+            safeSort(ids, (a, b) => a - b);
+        }
+        return new Value(safeMap(ids, (i) => this.originalArray[i]), size.context);
+    }
+    canShrinkWithoutContext(value) {
+        if (!safeArrayIsArray(value)) {
+            return false;
+        }
+        if (!this.lengthArb.canShrinkWithoutContext(value.length)) {
+            return false;
+        }
+        return isSubarrayOf(this.originalArray, value);
+    }
+    shrink(value, context) {
+        if (value.length === 0) {
+            return Stream.nil();
+        }
+        return this.lengthArb
+            .shrink(value.length, context)
+            .map((newSize) => {
+            return new Value(safeSlice(value, value.length - newSize.value), newSize.context);
+        })
+            .join(value.length > this.minLength
+            ? makeLazy(() => this.shrink(safeSlice(value, 1), undefined)
+                .filter((newValue) => this.minLength <= newValue.value.length + 1)
+                .map((newValue) => new Value([value[0], ...newValue.value], undefined)))
+            : Stream.nil());
+    }
+}