Add practice exercise markdown

config.json

@@ -369,6 +369,20 @@
           "strings"
         ]
       },
+      {
+        "slug": "markdown",
+        "name": "Markdown",
+        "uuid": "3994ee58-0d75-4c46-afe1-666466470255",
+        "practices": ["regular-expressions", "functions"],
+        "prerequisites": [],
+        "difficulty": 4,
+        "topics": [
+          "conditionals",
+          "pattern_recognition",
+          "regular_expressions",
+          "strings"
+        ]
+      },
       {
         "slug": "book-store",
         "name": "Book Store",

exercises/practice/markdown/.docs/instructions.md

@@ -0,0 +1,15 @@
+# Description
+
+Refactor a Markdown parser.
+
+The markdown exercise is a refactoring exercise. There is code that parses a
+given string with [Markdown
+syntax](https://guides.github.com/features/mastering-markdown/) and returns the
+associated HTML for that string. Even though this code is confusingly written
+and hard to follow, somehow it works and all the tests are passing! Your
+challenge is to re-write this code to make it easier to read and maintain
+while still making sure that all the tests keep passing.
+
+It would be helpful if you made notes of what you did in your refactoring in
+comments so reviewers can see that, but it isn't strictly necessary. The most
+important thing is to make the code better!

exercises/practice/markdown/.eslintrc

@@ -0,0 +1,14 @@
+{
+  "root": true,
+  "extends": "@exercism/eslint-config-javascript",
+  "env": {
+    "jest": true
+  },
+  "overrides": [
+    {
+      "files": [".meta/proof.ci.js", ".meta/exemplar.js", "*.spec.js"],
+      "excludedFiles": ["custom.spec.js"],
+      "extends": "@exercism/eslint-config-javascript/maintainers"
+    }
+  ]
+}

exercises/practice/markdown/.meta/config.json

@@ -0,0 +1,10 @@
+{
+  "blurb": "Refactor a Markdown parser.",
+  "authors": ["kmelow"],
+  "contributors": [],
+  "files": {
+    "solution": ["markdown.js"],
+    "test": ["markdown.spec.js"],
+    "example": [".meta/proof.ci.js"]
+  }
+}

exercises/practice/markdown/.meta/proof.ci.js

@@ -0,0 +1,72 @@
+//
+// This is only a SKELETON file for the 'Matrix' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export const parse = (markdown) => {
+  if (markdown.includes(' __')) {
+    markdown = markdown.replace(' __', ' <strong>');
+  }
+  if (markdown.includes(' _')) {
+    markdown = markdown.replace(' _', ' <em>');
+  }
+
+  if (markdown.includes('__ ')) {
+    markdown = markdown.replace('__ ', '</strong> ');
+  }
+  if (markdown.includes('_ ')) {
+    markdown = markdown.replace('_ ', '</em> ');
+  }
+
+  if (markdown.match(/__\w/g)) {
+    markdown = markdown.replace('__', '<strong>');
+  }
+  if (markdown.match(/\w__/g)) {
+    markdown = markdown.replace('__', '</strong>');
+  }
+
+  if (markdown.match(/_\w/g)) {
+    markdown = markdown.replace('_', '<em>');
+  }
+  if (markdown.match(/\w_/g)) {
+    markdown = markdown.replace('_', '</em>');
+  }
+
+  if (markdown.startsWith('# ')) {
+    markdown = markdown.replace('# ', '<h1>');
+    if (markdown.match(/\n\*/gm)) {
+      markdown = markdown.replace('\n* ', '</h1><ul><li>');
+      markdown = markdown.replaceAll('\n* ', '</li><li>');
+      if (markdown.match('\n')) {
+        markdown = markdown.replace('\n', '</li></ul><p>');
+        markdown = markdown + '</p>';
+      } else {
+        markdown = markdown + '</li></ul>';
+      }
+    } else {
+      markdown = markdown + '</h1>';
+    }
+  } else if (markdown.startsWith('## ')) {
+    markdown = markdown.replace('## ', '<h2>') + '</h2>';
+  } else if (markdown.startsWith('### ')) {
+    markdown = markdown.replace('### ', '<h3>') + '</h3>';
+  } else if (markdown.startsWith('#### ')) {
+    markdown = markdown.replace('#### ', '<h4>') + '</h4>';
+  } else if (markdown.startsWith('##### ')) {
+    markdown = markdown.replace('##### ', '<h5>') + '</h5>';
+  } else if (markdown.startsWith('###### ')) {
+    markdown = markdown.replace('###### ', '<h6>') + '</h6>';
+  } else if (markdown.startsWith('* ')) {
+    markdown = markdown.replace('* ', '<ul><li>');
+    markdown = markdown.replaceAll('\n* ', '</li><li>');
+    markdown = markdown + '</li></ul>';
+  } else {
+    markdown = `<p>${markdown}</p>`;
+  }
+
+  markdown = markdown.replace('\n* ', '<ul><li>');
+  markdown = markdown.replaceAll('\n* ', '</li><li>');
+  markdown = markdown.replace('\n', '<ul><li>');
+
+  return markdown;
+};

exercises/practice/markdown/.meta/tests.toml

@@ -0,0 +1,66 @@
+# 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.
+
+[e75c8103-a6b8-45d9-84ad-e68520545f6e]
+description = "parses normal text as a paragraph"
+
+[69a4165d-9bf8-4dd7-bfdc-536eaca80a6a]
+description = "parsing italics"
+
+[ec345a1d-db20-4569-a81a-172fe0cad8a1]
+description = "parsing bold text"
+
+[51164ed4-5641-4909-8fab-fbaa9d37d5a8]
+description = "mixed normal, italics and bold text"
+
+[ad85f60d-0edd-4c6a-a9b1-73e1c4790d15]
+description = "with h1 header level"
+
+[d0f7a31f-6935-44ac-8a9a-1e8ab16af77f]
+description = "with h2 header level"
+
+[9df3f500-0622-4696-81a7-d5babd9b5f49]
+description = "with h3 header level"
+
+[50862777-a5e8-42e9-a3b8-4ba6fcd0ed03]
+description = "with h4 header level"
+
+[ee1c23ac-4c86-4f2a-8b9c-403548d4ab82]
+description = "with h5 header level"
+
+[13b5f410-33f5-44f0-a6a7-cfd4ab74b5d5]
+description = "with h6 header level"
+
+[6dca5d10-5c22-4e2a-ac2b-bd6f21e61939]
+description = "with h7 header level"
+include = false
+
+[81c0c4db-435e-4d77-860d-45afacdad810]
+description = "h7 header level is a paragraph"
+reimplements = "6dca5d10-5c22-4e2a-ac2b-bd6f21e61939"
+
+[25288a2b-8edc-45db-84cf-0b6c6ee034d6]
+description = "unordered lists"
+
+[7bf92413-df8f-4de8-9184-b724f363c3da]
+description = "With a little bit of everything"
+
+[0b3ed1ec-3991-4b8b-8518-5cb73d4a64fe]
+description = "with markdown symbols in the header text that should not be interpreted"
+
+[113a2e58-78de-4efa-90e9-20972224d759]
+description = "with markdown symbols in the list item text that should not be interpreted"
+
+[e65e46e2-17b7-4216-b3ac-f44a1b9bcdb4]
+description = "with markdown symbols in the paragraph text that should not be interpreted"
+
+[f0bbbbde-0f52-4c0c-99ec-be4c60126dd4]
+description = "unordered lists close properly with preceding and following lines"

exercises/practice/markdown/.npmrc

@@ -0,0 +1 @@
+audit=false

exercises/practice/markdown/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 Exercism
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

exercises/practice/markdown/babel.config.js

@@ -0,0 +1,15 @@
+module.exports = {
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        targets: {
+          node: 'current',
+        },
+        useBuiltIns: 'entry',
+        corejs: '3.19',
+      },
+    ],
+  ],
+  plugins: ['@babel/plugin-syntax-bigint'],
+};

exercises/practice/markdown/markdown.js

@@ -0,0 +1,72 @@
+//
+// This is only a SKELETON file for the 'Matrix' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export const parse = (markdown) => {
+  if (markdown.includes(' __')) {
+    markdown = markdown.replace(' __', ' <strong>');
+  }
+  if (markdown.includes(' _')) {
+    markdown = markdown.replace(' _', ' <em>');
+  }
+
+  if (markdown.includes('__ ')) {
+    markdown = markdown.replace('__ ', '</strong> ');
+  }
+  if (markdown.includes('_ ')) {
+    markdown = markdown.replace('_ ', '</em> ');
+  }
+
+  if (markdown.match(/__\w/g)) {
+    markdown = markdown.replace('__', '<strong>');
+  }
+  if (markdown.match(/\w__/g)) {
+    markdown = markdown.replace('__', '</strong>');
+  }
+
+  if (markdown.match(/_\w/g)) {
+    markdown = markdown.replace('_', '<em>');
+  }
+  if (markdown.match(/\w_/g)) {
+    markdown = markdown.replace('_', '</em>');
+  }
+
+  if (markdown.startsWith('# ')) {
+    markdown = markdown.replace('# ', '<h1>');
+    if (markdown.match(/\n\*/gm)) {
+      markdown = markdown.replace('\n* ', '</h1><ul><li>');
+      markdown = markdown.replaceAll('\n* ', '</li><li>');
+      if (markdown.match('\n')) {
+        markdown = markdown.replace('\n', '</li></ul><p>');
+        markdown = markdown + '</p>';
+      } else {
+        markdown = markdown + '</li></ul>';
+      }
+    } else {
+      markdown = markdown + '</h1>';
+    }
+  } else if (markdown.startsWith('## ')) {
+    markdown = markdown.replace('## ', '<h2>') + '</h2>';
+  } else if (markdown.startsWith('### ')) {
+    markdown = markdown.replace('### ', '<h3>') + '</h3>';
+  } else if (markdown.startsWith('#### ')) {
+    markdown = markdown.replace('#### ', '<h4>') + '</h4>';
+  } else if (markdown.startsWith('##### ')) {
+    markdown = markdown.replace('##### ', '<h5>') + '</h5>';
+  } else if (markdown.startsWith('###### ')) {
+    markdown = markdown.replace('###### ', '<h6>') + '</h6>';
+  } else if (markdown.startsWith('* ')) {
+    markdown = markdown.replace('* ', '<ul><li>');
+    markdown = markdown.replaceAll('\n* ', '</li><li>');
+    markdown = markdown + '</li></ul>';
+  } else {
+    markdown = `<p>${markdown}</p>`;
+  }
+
+  markdown = markdown.replace('\n* ', '<ul><li>');
+  markdown = markdown.replaceAll('\n* ', '</li><li>');
+  markdown = markdown.replace('\n', '<ul><li>');
+
+  return markdown;
+};

exercises/practice/markdown/markdown.spec.js

@@ -0,0 +1,83 @@
+import { parse } from './markdown';
+
+describe('Markdown', () => {
+  test('test parses normal text as a paragraph', () => {
+    const markdown = 'This will be a paragraph';
+    expect(parse(markdown)).toMatch('<p>This will be a paragraph</p>');
+  });
+
+  xtest('test parsing italics', () => {
+    const markdown = '_This will be italic_';
+    expect(parse(markdown)).toMatch('<p><em>This will be italic</em></p>');
+  });
+
+  xtest('test parsing bold text', () => {
+    const markdown = '__This will be bold__';
+    expect(parse(markdown)).toMatch(
+      '<p><strong>This will be bold</strong></p>'
+    );
+  });
+
+  xtest('test mixed normal italics and bold text', () => {
+    const markdown = 'This will _be_ __mixed__';
+    expect(parse(markdown)).toMatch(
+      '<p>This will <em>be</em> <strong>mixed</strong></p>'
+    );
+  });
+
+  xtest('test with h1 header level', () => {
+    const markdown = '# This will be an h1';
+    expect(parse(markdown)).toMatch('<h1>This will be an h1</h1>');
+  });
+
+  xtest('test with h2 header level', () => {
+    const markdown = '## This will be an h2';
+    expect(parse(markdown)).toMatch('<h2>This will be an h2</h2>');
+  });
+
+  xtest('test with h6 header level', () => {
+    const markdown = '###### This will be an h6';
+    expect(parse(markdown)).toMatch('<h6>This will be an h6</h6>');
+  });
+
+  xtest('test unordered lists', () => {
+    const markdown = '* Item 1\n* Item 2';
+    expect(parse(markdown)).toMatch('<ul><li>Item 1</li><li>Item 2</li></ul>');
+  });
+
+  xtest('test with a little bit of everything', () => {
+    const markdown = '# Header!\n* __Bold Item__\n* _Italic Item_';
+    expect(parse(markdown)).toMatch(
+      '<h1>Header!</h1><ul><li><strong>Bold Item</strong></li><li><em>Italic Item</em></li></ul>'
+    );
+  });
+
+  xtest('test with markdown symbols in the header text that should not be interpreted', () => {
+    const markdown = '# This is a header with # and * in the text';
+    expect(parse(markdown)).toMatch(
+      '<h1>This is a header with # and * in the text</h1>'
+    );
+  });
+
+  xtest('test with markdown symbols in the list item text that should not be interpreted', () => {
+    const markdown =
+      '* Item 1 with a # in the text\n* Item 2 with * in the text';
+    expect(parse(markdown)).toMatch(
+      '<ul><li>Item 1 with a # in the text</li><li>Item 2 with * in the text</li></ul>'
+    );
+  });
+
+  xtest('test with markdown symbols in the paragraph text that should not be interpreted', () => {
+    const markdown = 'This is a paragraph with # and * in the text';
+    expect(parse(markdown)).toMatch(
+      '<p>This is a paragraph with # and * in the text</p>'
+    );
+  });
+
+  xtest('test unordered lists close properly with preceding and following lines', () => {
+    const markdown = '# Start a list\n* Item 1\n* Item 2\nEnd a list';
+    expect(parse(markdown)).toMatch(
+      '<h1>Start a list</h1><ul><li>Item 1</li><li>Item 2</li></ul><p>End a list</p>'
+    );
+  });
+});