Add update-docs command to generate dynamic README content.

Co-authored-by: Jonathan Jackson <[email protected]>

Author: Robert Jackson

commands/global/new.js

@@ -36,6 +36,11 @@ module.exports.handler = function handler(options) {
       ${projectName} <TRANSFORM NAME> path/of/files/ or/some**/*glob.js
       \`\`\`
 
+      ## Transforms
+
+      <!--TRANSFORMS_TABLE_START-->
+      <!--TRANSFORMS_TABLE_END-->
+
       ## Contributing
 
       ### Installation

commands/local/update-docs.js

@@ -0,0 +1,26 @@
+module.exports.command = 'update-docs';
+module.exports.desc = 'Update the project README with current list of transforms';
+
+module.exports.handler = function handler() {
+  const fs = require('fs-extra');
+
+  let TRANSFORMS_PLACE_HOLDER = /<!--TRANSFORMS_TABLE_START-->[\s\S]*<!--TRANSFORMS_TABLE_END-->/;
+
+  let transforms = fs
+    .readdirSync('transforms')
+    .filter(file => fs.lstatSync(`transforms/${file}`).isDirectory());
+
+  let readmeContent = transforms
+    .map(name => `* [${name}](transforms/${name}/README.md)`)
+    .join('\n');
+
+  fs.writeFileSync(
+    'README.md',
+    fs
+      .readFileSync('README.md', 'utf8')
+      .replace(
+        TRANSFORMS_PLACE_HOLDER,
+        `<!--TRANSFORMS_TABLE_START-->\n${readmeContent}\n<!--TRANSFORMS_TABLE_END-->`
+      )
+  );
+};

tests/cli-test.js

@@ -74,6 +74,28 @@ QUnit.module('codemod-cli', function(hooks) {
     );
   });
 
+  QUnit.module('update-docs', function(hooks) {
+    setupProject(hooks);
+
+    QUnit.test(
+      'updates top-level README with links to transform READMEs',
+      wrap(function*(assert) {
+        codemodProject.write({
+          transforms: {
+            foo: { 'README.md': 'some content' },
+            bar: { 'README.md': 'some content' },
+          },
+        });
+
+        yield execa(EXECUTABLE_PATH, ['update-docs']);
+
+        let README = fs.readFileSync(codemodProject.path('README.md'), 'utf8');
+        assert.ok(README.includes('* [foo](transforms/foo/README.md'), 'foo link');
+        assert.ok(README.includes('* [bar](transforms/bar/README.md'), 'bar link');
+      })
+    );
+  });
+
   QUnit.module('generate', function(hooks) {
     setupProject(hooks);