feat: analyze dependencies when loaded

gulpfile.js

@@ -43,7 +43,7 @@ gulp.task('clean', () => {
 
 gulp.task('build', ['clean', 'lint'], () => {
   return gulp
-    .src(path.join(__dirname, 'src', 'index.js'))
+    .src(path.join(__dirname, 'src', '*.js'))
     .pipe(babel())
     .pipe(gulp.dest(path.join(__dirname, 'dist')));
 });

src/index.js

@@ -22,70 +22,8 @@
  * SOFTWARE.
  */
 
-const fs = require('fs');
-const path = require('path');
-const _ = require('lodash');
-const moment = require('moment');
-const MagicString = require('magic-string');
-
-const EOL = '\n';
+const LicensePlugin = require('./license-plugin.js');
 
 module.exports = (options = {}) => {
-  return {
-    transformBundle(code) {
-      const file = options.file || 'LICENSE';
-      const filePath = path.resolve(file);
-
-      const exists = fs.existsSync(filePath);
-      if (!exists) {
-        return {code};
-      }
-
-      const content = fs.readFileSync(filePath, 'utf-8');
-
-      // Import the `package.json` of the project.
-      // Use `process.cdwd()`
-      const pkgPath = path.resolve(process.cwd(), 'package.json');
-      const pkg = require(pkgPath);
-
-      // Create the template function with lodash.
-      const tmpl = _.template(content);
-
-      // Generate the banner.
-      let banner = tmpl({_, moment, pkg});
-
-      // Make a block comment if needed
-      const trimmedBanner = banner.trim();
-      const start = trimmedBanner.slice(0, 3);
-      if (start !== '/**') {
-        const bannerContent = trimmedBanner
-          .split(`${EOL}`)
-          .map((line) => _.trimEnd(` * ${line}`))
-          .join(`${EOL}`);
-
-        banner = `/**${EOL}${bannerContent}${EOL} */${EOL}`;
-      }
-
-      // Create a magicString: do not manipulate the string directly since it
-      // will be used to generate the sourcemap.
-      const magicString = new MagicString(code);
-
-      // Prepend the banner.
-      magicString.prepend(`${banner}${EOL}`);
-
-      // Create the result object.
-      const result = {
-        code: magicString.toString(),
-      };
-
-      // Add sourceMap information if it is enabled.
-      if (options.sourceMap !== false) {
-        result.map = magicString.generateMap({
-          hires: true,
-        });
-      }
-
-      return result;
-    },
-  };
+  return new LicensePlugin(options);
 };

src/license-plugin.js

@@ -0,0 +1,160 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Mickael Jeanroy
+ *
+ * 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.
+ */
+
+const fs = require('fs');
+const path = require('path');
+const _ = require('lodash');
+const moment = require('moment');
+const MagicString = require('magic-string');
+const EOL = '\n';
+
+/**
+ * Rollup Plugin.
+ */
+class LicensePlugin {
+  /**
+   * Initialize plugin.
+   *
+   * @param {Object} options Plugin options.
+   */
+  constructor(options = {}) {
+    this._options = options;
+    this._cwd = process.cwd();
+    this._dependencies = [];
+    this._pkg = require(path.join(this._cwd, 'package.json'));
+  }
+
+  /**
+   * Hook triggered by `rollup` to load code from given path file.
+   *
+   * This hook is used here to analyze a JavaScript file to extract
+   * associated `package.json` file and store the main information about
+   * it (license, author, etc.).
+   *
+   * This method is used to analyse all the files added to the final bundle
+   * to extract license informations.
+   *
+   * @param {string} id Module identifier.
+   * @return {void}
+   */
+  load(id) {
+    // Look for the `package.json` file
+    let dir = path.parse(id).dir;
+    while (dir && dir !== this._cwd) {
+      const pkg = path.join(dir, 'package.json');
+      const exists = fs.existsSync(pkg);
+
+      if (exists) {
+        this.addDependency(require(pkg));
+        break;
+      }
+
+      const parent = path.join(dir, '..');
+      dir = path.normalize(parent);
+    }
+  }
+
+  /**
+   * Hook triggered by `rollup` to transform the final generated bundle.
+   * This hook is used here to prepend the license banner to the final bundle.
+   *
+   * @param {string} code The bundle content.
+   * @return {Object} The result containing the code and, optionnally, the source map.
+   */
+  transformBundle(code) {
+    const file = this._options.file || 'LICENSE';
+    const filePath = path.resolve(file);
+
+    const exists = fs.existsSync(filePath);
+    if (!exists) {
+      return {code};
+    }
+
+    const content = fs.readFileSync(filePath, 'utf-8');
+
+    // Create the template function with lodash.
+    const tmpl = _.template(content);
+
+    // Generate the banner.
+    let banner = tmpl({
+      _,
+      moment,
+      pkg: this._pkg,
+      dependencies: this._dependencies,
+    });
+
+    // Make a block comment if needed
+    const trimmedBanner = banner.trim();
+    const start = trimmedBanner.slice(0, 3);
+    if (start !== '/**') {
+      const bannerContent = trimmedBanner
+        .split(`${EOL}`)
+        .map((line) => _.trimEnd(` * ${line}`))
+        .join(`${EOL}`);
+
+      banner = `/**${EOL}${bannerContent}${EOL} */${EOL}`;
+    }
+
+    // Create a magicString: do not manipulate the string directly since it
+    // will be used to generate the sourcemap.
+    const magicString = new MagicString(code);
+
+    // Prepend the banner.
+    magicString.prepend(`${banner}${EOL}`);
+
+    // Create the result object.
+    const result = {
+      code: magicString.toString(),
+    };
+
+    // Add sourceMap information if it is enabled.
+    if (this._options.sourceMap !== false) {
+      result.map = magicString.generateMap({
+        hires: true,
+      });
+    }
+
+    return result;
+  }
+
+  /**
+   * Add new dependency to the bundle descriptor.
+   *
+   * @param {Object} pkg Dependency package information.
+   * @return {void}
+   */
+  addDependency(pkg) {
+    this._dependencies.push(_.pick(pkg, [
+      'name',
+      'author',
+      'version',
+      'description',
+      'license',
+      'repository',
+      'homepage',
+    ]));
+  }
+}
+
+module.exports = LicensePlugin;

test/fixtures/banner-with-dependencies.js

@@ -0,0 +1,8 @@
+/**
+ * Name: <%= pkg.name %>
+ *
+ * Dependencies:
+ * <% _.forEach(dependencies, function (dependency) { %>
+ *   <%= dependency.name %> -- <%= dependency.license %>
+ * <% }); %>
+ */

test/fixtures/fake-package/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "fake-package",
+  "version": "1.0.0",
+  "description": "Fake package used in unit tests",
+  "main": "src/index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "Mickael Jeanroy <mickael.jeanroy@gmail.com>",
+  "license": "MIT",
+  "private": "true"
+}

test/fixtures/fake-package/src/index.js

@@ -0,0 +1,25 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Mickael Jeanroy
+ *
+ * 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.
+ */
+
+console.log('fake-package');