refactor: change separate tools by category

core/stdlib/src/bits/flags/index.test.ts

@@ -0,0 +1,26 @@
+import { describe, it, expect } from 'vitest';
+import { flagsGenerator } from '.';
+
+describe('flagsGenerator', () => {
+  it('generate unique flags', () => {
+    const generateFlag = flagsGenerator();
+
+    const flag1 = generateFlag();
+    const flag2 = generateFlag();
+    const flag3 = generateFlag();
+
+    expect(flag1).toBe(1);
+    expect(flag2).toBe(2);
+    expect(flag3).toBe(4);
+  });
+
+  it('throw an error if more than 31 flags are created', () => {
+    const generateFlag = flagsGenerator();
+
+    for (let i = 0; i < 31; i++) {
+      generateFlag();
+    }
+
+    expect(() => generateFlag()).toThrow(new RangeError('Cannot create more than 31 flags'));
+  });
+});

core/stdlib/src/bits/flags/index.ts

@@ -0,0 +1,22 @@
+/**
+ * @name flagsGenerator
+ * @category Bits
+ * @description Create a function that generates unique flags
+ * 
+ * @returns {Function} A function that generates unique flags
+ * @throws {RangeError} If more than 31 flags are created
+ *
+ * @since 0.0.2
+ */
+export function flagsGenerator() {
+    let lastFlag = 0;
+
+    return () => {
+      // 31 flags is the maximum number of flags that can be created
+      // (without zero) because of the 32-bit integer limit in bitwise operations
+      if (lastFlag & 0x40000000)
+        throw new RangeError('Cannot create more than 31 flags');
+
+      return (lastFlag = lastFlag === 0 ? 1 : lastFlag << 1);
+    };
+}

core/stdlib/src/bits/helpers/index.test.ts

@@ -0,0 +1,95 @@
+import { describe, it, expect } from 'vitest';
+import { and, or, not, has, is, unset, toggle } from '.';
+
+
+describe('flagsAnd', () => {
+  it('no effect on zero flags', () => {
+    const result = and();
+
+    expect(result).toBe(-1);
+  });
+
+  it('source flag is returned if no flags are provided', () => {
+    const result = and(0b1010);
+
+    expect(result).toBe(0b1010);
+  });
+  
+  it('perform bitwise AND operation on flags', () => {
+    const result = and(0b1111, 0b1010, 0b1100);
+
+    expect(result).toBe(0b1000);
+  });
+});
+
+describe('flagsOr', () => {
+  it('no effect on zero flags', () => {
+    const result = or();
+
+    expect(result).toBe(0);
+  });
+
+  it('source flag is returned if no flags are provided', () => {
+      const result = or(0b1010);
+  
+      expect(result).toBe(0b1010);
+  });
+
+  it('perform bitwise OR operation on flags', () => {
+      const result = or(0b1111, 0b1010, 0b1100);
+  
+      expect(result).toBe(0b1111);
+  });
+});
+
+describe('flagsNot', () => {
+  it('perform bitwise NOT operation on a flag', () => {
+    const result = not(0b101);
+
+    expect(result).toBe(-0b110);
+  });
+});
+
+describe('flagsHas', () => {
+  it('check if a flag has a specific bit set', () => {
+    const result = has(0b1010, 0b1000);
+
+    expect(result).toBe(true);
+  });
+
+  it('check if a flag has a specific bit unset', () => {
+      const result = has(0b1010, 0b0100);
+  
+      expect(result).toBe(false);
+  });
+});
+
+describe('flagsIs', () => {
+  it('check if a flag is set', () => {
+    const result = is(0b1010);
+
+    expect(result).toBe(true);
+  });
+
+  it('check if a flag is unset', () => {
+      const result = is(0);
+  
+      expect(result).toBe(false);
+  });
+});
+
+describe('flagsUnset', () => {
+  it('unset a flag', () => {
+    const result = unset(0b1010, 0b1000);
+
+    expect(result).toBe(0b0010);
+  });
+});
+
+describe('flagsToggle', () => {
+  it('toggle a flag', () => {
+    const result = toggle(0b1010, 0b1000);
+
+    expect(result).toBe(0b0010);
+  });
+});

core/stdlib/src/bits/helpers/index.ts

@@ -0,0 +1,100 @@
+/**
+ * @name and
+ * @category Bits
+ * @description Function to combine multiple flags using the AND operator
+ * 
+ * @param {number[]} flags - The flags to combine
+ * @returns {number} The combined flags
+ *
+ * @since 0.0.2
+ */
+export function and(...flags: number[]) {
+  return flags.reduce((acc, flag) => acc & flag, -1);
+}
+
+/**
+* @name or
+* @category Bits
+* @description Function to combine multiple flags using the OR operator
+* 
+* @param {number[]} flags - The flags to combine
+* @returns {number} The combined flags
+*
+* @since 0.0.2
+*/
+export function or(...flags: number[]) {
+  return flags.reduce((acc, flag) => acc | flag, 0);
+}
+
+/**
+* @name not
+* @category Bits
+* @description Function to combine multiple flags using the XOR operator
+* 
+* @param {number} flag - The flag to apply the NOT operator to
+* @returns {number} The result of the NOT operator
+*
+* @since 0.0.2
+*/
+export function not(flag: number) {
+  return ~flag;
+}
+
+/**
+* @name has
+* @category Bits
+* @description Function to make sure a flag has a specific bit set
+* 
+* @param {number} flag - The flag to check
+* @param {number} other - Flag to check
+* @returns {boolean} Whether the flag has the bit set
+*
+* @since 0.0.2
+*/
+export function has(flag: number, other: number) {
+  return (flag & other) === other;
+}
+
+/**
+* @name is
+* @category Bits
+* @description Function to check if a flag is set
+* 
+* @param {number} flag - The flag to check
+* @returns {boolean} Whether the flag is set
+*
+* @since 0.0.2
+*/
+export function is(flag: number) {
+  return flag !== 0;
+}
+
+/**
+* @name unset
+* @category Bits
+* @description Function to unset a flag
+* 
+* @param {number} flag - Source flag
+* @param {number} other - Flag to unset
+* @returns {number} The new flag
+*
+* @since 0.0.2
+*/
+export function unset(flag: number, other: number) {
+  return flag & ~other;
+}
+
+/**
+* @name toggle
+* @category Bits
+* @description Function to toggle (xor) a flag
+* 
+* @param {number} flag - Source flag
+* @param {number} other - Flag to toggle
+* @returns {number} The new flag
+*
+* @since 0.0.2
+*/
+export function toggle(flag: number, other: number) {
+  return flag ^ other;
+}

core/stdlib/src/bits/index.ts

@@ -0,0 +1 @@
+export * from './flags';

core/stdlib/src/bits/vector/index.test.ts

@@ -0,0 +1,63 @@
+import { describe, it, expect } from 'vitest';
+import { BitVector } from '.';
+
+describe('BitVector', () => {
+  it('initialize with the correct size', () => {
+    const size = 16;
+    const expectedSize = Math.ceil(size / 8);
+    const bitVector = new BitVector(size);
+
+    expect(bitVector.length).toBe(expectedSize);
+  });
+
+  it('set and get bits correctly', () => {
+    const bitVector = new BitVector(16);
+    bitVector.setBit(5);
+    
+    expect(bitVector.getBit(5)).toBe(true);
+    expect(bitVector.getBit(4)).toBe(false);
+  });
+
+  it('get out of bounds bits correctly', () => {
+    const bitVector = new BitVector(16);
+
+    expect(bitVector.getBit(155)).toBe(false);
+  });
+
+  it('clear bits correctly', () => {
+    const bitVector = new BitVector(16);
+    bitVector.setBit(5);
+
+    expect(bitVector.getBit(5)).toBe(true);
+
+    bitVector.clearBit(5);
+
+    expect(bitVector.getBit(5)).toBe(false);
+  });
+
+  it('find the previous bit correctly', () => {
+    const bitVector = new BitVector(100);
+    const indices = [99, 88, 66, 65, 64, 63, 15, 14, 1, 0];
+    const result = [];
+    indices.forEach(index => bitVector.setBit(index));
+    
+    for (let i = bitVector.previousBit(100); i !== -1; i = bitVector.previousBit(i)) {
+      result.push(i);
+    }
+
+    expect(result).toEqual(indices);
+  });
+
+  it('return -1 when no previous bit is found', () => {
+    const bitVector = new BitVector(16);
+
+    expect(bitVector.previousBit(0)).toBe(-1);
+  });
+
+  it('throw RangeError when previousBit is called with an unreachable value', () => {
+    const bitVector = new BitVector(16);
+    bitVector.setBit(5);
+
+    expect(() => bitVector.previousBit(24)).toThrow(new RangeError('Unreachable value'));
+  });
+});

core/stdlib/src/bits/vector/index.ts

@@ -0,0 +1,61 @@
+export interface BitVector {
+  getBit(index: number): boolean;
+  setBit(index: number): void;
+  clearBit(index: number): void;
+  previousBit(index: number): number;
+}
+
+/**
+ * @name BitVector
+ * @category Bits
+ * @description A bit vector is a vector of bits that can be used to store a collection of bits
+ * 
+ * @since 0.0.3
+ */
+export class BitVector extends Uint8Array implements BitVector {
+  constructor(size: number) {
+    super(Math.ceil(size / 8));
+  }
+
+  getBit(index: number) {
+    const value = this[index >> 3]! & (1 << (index & 7));
+    return value !== 0;
+  }
+
+  setBit(index: number) {
+    this[index >> 3]! |= 1 << (index & 7);
+  }
+
+  clearBit(index: number): void {
+    this[index >> 3]! &= ~(1 << (index & 7));
+  }
+
+  previousBit(index: number): number {
+    while (index !== ((index >> 3) << 3)) {
+      --index;
+
+      if (this.getBit(index)) {
+        return index;
+      }
+    }
+
+    let byteIndex = (index >> 3) - 1;
+
+    while (byteIndex >= 0 && this[byteIndex] === 0)
+      --byteIndex;
+
+    if (byteIndex < 0)
+      return -1;
+
+    index = (byteIndex << 3) + 7;
+
+    while (index >= (byteIndex << 3)) {
+      if (this.getBit(index))
+        return index;
+
+      --index;
+    }
+
+    throw new RangeError('Unreachable value');
+  }
+}