Pop count

config.json

@@ -1039,6 +1039,14 @@
         "difficulty": 3,
         "topics": ["classes", "conditionals"]
       },
+      {
+        "slug": "pop-count",
+        "name": "Eliud's Eggs",
+        "uuid": "2cdf947c-34ed-4ecf-92dd-4c4e6c21f9f3",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "rotational-cipher",
         "name": "Rotational Cipher",

exercises/practice/pop-count/.docs/instructions.md

@@ -0,0 +1,8 @@
+# Instructions
+
+Your task is to count the number of 1 bits in the binary representation of a number.
+
+## Restrictions
+
+Keep your hands off that bit-count functionality provided by your standard library!
+Solve this one yourself using other basic tools instead.

exercises/practice/pop-count/.docs/introduction.md

@@ -0,0 +1,47 @@
+# Introduction
+
+Your friend Eliud inherited a farm from her grandma Tigist.
+Her granny was an inventor and had a tendency to build things in an overly complicated manner.
+The chicken coop has a digital display showing an encoded number representing the positions of all eggs that could be picked up.
+
+Eliud is asking you to write a program that shows the actual number of eggs in the coop.
+
+The position information encoding is calculated as follows:
+
+1. Scan the potential egg-laying spots and mark down a `1` for an existing egg or a `0` for an empty spot.
+2. Convert the number from binary to decimal.
+3. Show the result on the display.
+
+Example 1:
+
+```text
+Chicken Coop:
+ _ _ _ _ _ _ _
+|E| |E|E| | |E|
+
+Resulting Binary:
+ 1 0 1 1 0 0 1
+
+Decimal number on the display:
+89
+
+Actual eggs in the coop:
+4
+```
+
+Example 2:
+
+```text
+Chicken Coop:
+ _ _ _ _ _ _ _ _
+| | | |E| | | | |
+
+Resulting Binary:
+ 0 0 0 1 0 0 0 0
+
+Decimal number on the display:
+16
+
+Actual eggs in the coop:
+1
+```

exercises/practice/pop-count/.eslintignore

@@ -0,0 +1,13 @@
+!.meta
+
+# Protected or generated
+.git
+.vscode
+
+# When using npm
+node_modules/*
+
+# Configuration files
+.eslintrc.cjs
+babel.config.cjs
+jest.config.cjs

exercises/practice/pop-count/.eslintrc.cjs

@@ -0,0 +1,38 @@
+module.exports = {
+  root: true,
+  parserOptions: {
+    tsconfigRootDir: __dirname,
+    project: ['./tsconfig.json'],
+  },
+  overrides: [
+    // Student provided files
+    {
+      files: ['*.ts'],
+      excludedFiles: ['.meta/proof.ci.ts', '.meta/exemplar.ts', '*.test.ts'],
+      extends: '@exercism/eslint-config-typescript',
+    },
+    // Exercism given tests
+    {
+      files: ['*.test.ts'],
+      excludedFiles: ['custom.test.ts'],
+      env: {
+        jest: true,
+      },
+      extends: '@exercism/eslint-config-typescript/maintainers',
+    },
+    // Student provided tests
+    {
+      files: ['custom.test.ts'],
+      env: {
+        jest: true,
+      },
+      extends: '@exercism/eslint-config-typescript',
+    },
+    // Exercism provided files
+    {
+      files: ['.meta/proof.ci.ts', '.meta/exemplar.ts', '*.test.ts'],
+      excludedFiles: ['custom.test.ts'],
+      extends: '@exercism/eslint-config-typescript/maintainers',
+    },
+  ],
+}

exercises/practice/pop-count/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "therealowenrees"
+  ],
+  "files": {
+    "solution": [
+      "pop-count.ts"
+    ],
+    "test": [
+      "pop-count.test.ts"
+    ],
+    "example": [
+      ".meta/proof.ci.ts"
+    ]
+  },
+  "blurb": "Help Eliud count the number of eggs in her chicken coop by counting the number of 1 bits in a binary representation.",
+  "source": "Christian Willner, Eric Willigers",
+  "source_url": "https://forum.exercism.org/t/new-exercise-suggestion-pop-count/7632/5"
+}

exercises/practice/pop-count/.meta/proof.ci.ts

@@ -0,0 +1,10 @@
+export const eggCount = (displayValue: number): number => {
+  let count = 0
+
+  while (displayValue !== 0) {
+    count += displayValue & 1
+    displayValue >>= 1
+  }
+
+  return count
+}

exercises/practice/pop-count/.meta/tests.toml

@@ -0,0 +1,22 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[559e789d-07d1-4422-9004-3b699f83bca3]
+description = "0 eggs"
+
+[97223282-f71e-490c-92f0-b3ec9e275aba]
+description = "1 egg"
+
+[1f8fd18f-26e9-4144-9a0e-57cdfc4f4ff5]
+description = "4 eggs"
+
+[0c18be92-a498-4ef2-bcbb-28ac4b06cb81]
+description = "13 eggs"

exercises/practice/pop-count/.yarnrc.yml

@@ -0,0 +1 @@
+yarnPath: .yarn/releases/yarn-3.6.4.cjs

exercises/practice/pop-count/babel.config.cjs

@@ -0,0 +1,4 @@
+module.exports = {
+  presets: ['@exercism/babel-preset-typescript'],
+  plugins: [],
+}

exercises/practice/pop-count/jest.config.cjs

@@ -0,0 +1,19 @@
+module.exports = {
+  verbose: true,
+  projects: ['<rootDir>'],
+  testMatch: [
+    '**/__tests__/**/*.[jt]s?(x)',
+    '**/test/**/*.[jt]s?(x)',
+    '**/?(*.)+(spec|test).[jt]s?(x)',
+  ],
+  testPathIgnorePatterns: [
+    '/(?:production_)?node_modules/',
+    '.d.ts$',
+    '<rootDir>/test/fixtures',
+    '<rootDir>/test/helpers',
+    '__mocks__',
+  ],
+  transform: {
+    '^.+\\.[jt]sx?$': 'babel-jest',
+  },
+}

exercises/practice/pop-count/package.json

@@ -0,0 +1,32 @@
+{
+  "name": "@exercism/typescript-pop-count",
+  "version": "1.0.0",
+  "description": "Exercism exercises in Typescript.",
+  "private": true,
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/exercism/typescript"
+  },
+  "type": "module",
+  "engines": {
+    "node": "^18.16.0 || >=20.0.0"
+  },
+  "devDependencies": {
+    "@exercism/babel-preset-typescript": "^0.4.0",
+    "@exercism/eslint-config-typescript": "^0.5.0",
+    "@types/jest": "^29.5.2",
+    "@types/node": "~18.16.16",
+    "babel-jest": "^29.5.0",
+    "core-js": "~3.30.2",
+    "eslint": "^8.42.0",
+    "jest": "^29.5.0",
+    "typescript": "~5.0.4"
+  },
+  "scripts": {
+    "test": "yarn lint:types && jest --no-cache",
+    "lint": "yarn lint:types && yarn lint:ci",
+    "lint:types": "yarn tsc --noEmit -p .",
+    "lint:ci": "eslint . --ext .tsx,.ts"
+  },
+  "packageManager": "yarn@3.6.4"
+}

exercises/practice/pop-count/pop-count.test.ts

@@ -0,0 +1,27 @@
+import { eggCount } from './pop-count'
+
+describe('PopCount', () => {
+  it('0 eggs', () => {
+    const expected = 0
+    const actual = eggCount(0)
+    expect(actual).toEqual(expected)
+  })
+
+  xit('1 egg', () => {
+    const expected = 1
+    const actual = eggCount(16)
+    expect(actual).toEqual(expected)
+  })
+
+  xit('4 eggs', () => {
+    const expected = 4
+    const actual = eggCount(89)
+    expect(actual).toEqual(expected)
+  })
+
+  xit('13 eggs', () => {
+    const expected = 13
+    const actual = eggCount(2000000000)
+    expect(actual).toEqual(expected)
+  })
+})

exercises/practice/pop-count/pop-count.ts

@@ -0,0 +1,8 @@
+//
+// This is only a SKELETON file for the 'Pop Count' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export const eggCount = (displayValue: unknown): unknown => {
+  throw new Error('Remove this statement and implement this function')
+}

exercises/practice/pop-count/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "display": "Configuration for Exercism TypeScript Exercises",
+  "compilerOptions": {
+    // Allows you to use the newest syntax, and have access to console.log
+    // https://www.typescriptlang.org/tsconfig#lib
+    "lib": ["ESNEXT", "dom"],
+    // Make sure typescript is configured to output ESM
+    // https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c#how-can-i-make-my-typescript-project-output-esm
+    "module": "ES2020",
+    // Since this project is using babel, TypeScript may target something very
+    // high, and babel will make sure it runs on your local Node version.
+    // https://babeljs.io/docs/en/
+    "target": "ESNext", // ESLint doesn't support this yet: "es2022",
+
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+
+    // Because we'll be using babel: ensure that Babel can safely transpile
+    // files in the TypeScript project.
+    //
+    // https://babeljs.io/docs/en/babel-plugin-transform-typescript/#caveats
+    "isolatedModules": true
+  },
+  "include": ["*.ts", "*.tsx", ".meta/*.ts", ".meta/*.tsx"],
+  "exclude": ["node_modules"]
+}