Build: autogenerate the table in README.md (fixes #43)

README.md

@@ -46,22 +46,24 @@ Then configure the rules you want to use under the rules section.
 ✔️ indicates that a rule is recommended for all users.
 🛠 indicates that a rule is fixable.
 
+<!-- __BEGIN AUTOGENERATED TABLE__ -->
 Name | ✔️ | 🛠 | Description
 ----- | ----- | ----- | -----
-[consistent-output](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/consistent-output.md) | | | Enforces consistent use of output assertions in rule tests
-[fixer-return](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/fixer-return.md) | ✔️ | | Enforces always return from a fixer function
-[no-deprecated-context-methods](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-deprecated-context-methods.md) | | 🛠 | Disallows usage of deprecated methods on rule context objects
-[no-deprecated-report-api](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-deprecated-report-api.md) | ✔️ | 🛠 | Prohibits the deprecated `context.report(node, message)` API
-[no-identical-tests](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-identical-tests.md) | ✔️  | 🛠 | Disallows identical tests
-[no-missing-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-missing-placeholders.md) | ✔️ | | Disallows missing placeholders in rule report messages
-[no-unused-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-unused-placeholders.md) | ✔️ | | Disallows unused placeholders in rule report messages
-[no-useless-token-range](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-useless-token-range.md) | ✔️ | 🛠 | Disallows unnecessary calls to sourceCode.getFirstToken and sourceCode.getLastToken
-[prefer-output-null](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/prefer-output-null.md) | | 🛠 | Disallows invalid RuleTester test cases with the output the same as the code.
-[prefer-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/prefer-placeholders.md) | | | Disallows template literals as report messages
-[report-message-format](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/report-message-format.md) | | | Enforces a consistent format for report messages
-[require-meta-fixable](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/require-meta-fixable.md) | ✔️ | | Requires a `meta.fixable` property for fixable rules
-[test-case-property-ordering](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/test-case-property-ordering.md) | | 🛠 | Requires the properties of a test case to be placed in a consistent order.
-[test-case-shorthand-strings](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/test-case-shorthand-strings.md) | | 🛠 | Enforces consistent usage of shorthand strings for test cases with no options
+[consistent-output](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/consistent-output.md) |  |  | Enforce consistent use of output assertions in rule tests
+[fixer-return](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/fixer-return.md) | ✔️ |  | Expected fixer function to always return a value.
+[no-deprecated-context-methods](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-deprecated-context-methods.md) |  | 🛠 | Disallows usage of deprecated methods on rule context objects
+[no-deprecated-report-api](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-deprecated-report-api.md) | ✔️ | 🛠 | disallow use of the deprecated context.report() API
+[no-identical-tests](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-identical-tests.md) | ✔️ | 🛠 | disallow identical tests
+[no-missing-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-missing-placeholders.md) | ✔️ |  | Disallow missing placeholders in rule report messages
+[no-unused-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-unused-placeholders.md) | ✔️ |  | Disallow unused placeholders in rule report messages
+[no-useless-token-range](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/no-useless-token-range.md) | ✔️ | 🛠 | Disallow unnecessary calls to sourceCode.getFirstToken and sourceCode.getLastToken
+[prefer-output-null](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/prefer-output-null.md) |  | 🛠 | disallows invalid RuleTester test cases with the output the same as the code.
+[prefer-placeholders](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/prefer-placeholders.md) |  |  | disallow template literals as report messages
+[report-message-format](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/report-message-format.md) |  |  | enforce a consistent format for rule report messages
+[require-meta-fixable](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/require-meta-fixable.md) | ✔️ |  | require rules to implement a meta.fixable property
+[test-case-property-ordering](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/test-case-property-ordering.md) |  | 🛠 | Requires the properties of a test case to be placed in a consistent order
+[test-case-shorthand-strings](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/test-case-shorthand-strings.md) |  | 🛠 | Enforce consistent usage of shorthand strings for test cases with no options
+<!-- __END AUTOGENERATED TABLE__ -->
 
 ## Supported Presets
 

build/generate-readme-table.js

@@ -0,0 +1,48 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const rules = require('..').rules;
+
+const README_LOCATION = path.resolve(__dirname, '..', 'README.md');
+const BEGIN_TABLE_MARKER = '<!-- __BEGIN AUTOGENERATED TABLE__ -->\n';
+const END_TABLE_MARKER = '\n<!-- __END AUTOGENERATED TABLE__ -->';
+
+const expectedTableLines = Object.keys(rules)
+  .sort()
+  .reduce((lines, ruleId) => {
+    const rule = rules[ruleId];
+
+    lines.push([
+      `[${ruleId}](https://github.com/not-an-aardvark/eslint-plugin-eslint-plugin/blob/master/docs/rules/${ruleId}.md)`,
+      rule.meta.docs.recommended ? '✔️' : '',
+      rule.meta.fixable ? '🛠' : '',
+      rule.meta.docs.description,
+    ].join(' | '));
+
+    return lines;
+  }, ['Name | ✔️ | 🛠 | Description', '----- | ----- | ----- | -----'])
+  .join('\n');
+
+const readmeContents = fs.readFileSync(README_LOCATION, 'utf8');
+
+if (!readmeContents.includes(BEGIN_TABLE_MARKER)) {
+  throw new Error(`Could not find '${BEGIN_TABLE_MARKER}' marker in README.md.`);
+}
+
+if (!readmeContents.includes(END_TABLE_MARKER)) {
+  throw new Error(`Could not find '${END_TABLE_MARKER}' marker in README.md.`);
+}
+
+const linesStartIndex = readmeContents.indexOf(BEGIN_TABLE_MARKER) + BEGIN_TABLE_MARKER.length;
+const linesEndIndex = readmeContents.indexOf(END_TABLE_MARKER);
+
+const updatedReadmeContents = readmeContents.slice(0, linesStartIndex) +
+  expectedTableLines +
+  readmeContents.slice(linesEndIndex);
+
+if (module.parent) {
+  module.exports = updatedReadmeContents;
+} else {
+  fs.writeFileSync(README_LOCATION, updatedReadmeContents);
+}

package.json

@@ -8,6 +8,7 @@
   "scripts": {
     "lint": "eslint . --ignore-pattern \"!.*\"",
     "pretest": "npm run lint",
+    "generate-readme-table": "node build/generate-readme-table.js",
     "generate-release": "node-release-script",
     "test": "mocha tests --recursive"
   },

tests/build/generate-readme-table.js

@@ -0,0 +1,17 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const assert = require('chai').assert;
+
+describe('table in README.md', () => {
+  it('is up-to-date', () => {
+    const actualReadme = fs.readFileSync(path.resolve(__dirname, '..', '..', 'README.md'), 'utf8');
+    const expectedReadme = require('../../build/generate-readme-table');
+
+    assert(
+      actualReadme === expectedReadme,
+      'The table in README.md is out of date. Please use `npm run generate-readme-table` to update it.'
+    );
+  });
+});