From e7500033924e98a64c98f6e8637feca0c74a0262 Mon Sep 17 00:00:00 2001
From: Mickael Jeanroy <mickael.jeanroy@gmail.com>
Date: Tue, 11 Jun 2019 12:49:04 +0200
Subject: [PATCH] fix: exclude tree shaken modules from dependencies to scan

---
 src/index-rollup-stable.js       | 21 ++++++++++----------
 src/license-plugin.js            | 18 +++++++++++++++--
 test/index-rollup-stable.spec.js | 34 ++++++++++++++++++++++++++++----
 test/license-plugin.spec.js      | 29 +++++++++++++++++++++++++++
 4 files changed, 85 insertions(+), 17 deletions(-)

diff --git a/src/index-rollup-stable.js b/src/index-rollup-stable.js
index 77415cf8..352a5dcf 100644
--- a/src/index-rollup-stable.js
+++ b/src/index-rollup-stable.js
@@ -24,6 +24,7 @@
 
 'use strict';
 
+const _ = require('lodash');
 const LicensePlugin = require('./license-plugin.js');
 
 module.exports = (options = {}) => {
@@ -36,17 +37,6 @@ module.exports = (options = {}) => {
      */
     name: plugin.name,
 
-    /**
-     * Function called by rollup when a JS file is loaded: it is used to scan
-     * third-party dependencies.
-     *
-     * @param {string} id JS file path.
-     * @return {void}
-     */
-    load(id) {
-      plugin.scanDependency(id);
-    },
-
     /**
      * Function called by rollup when the final bundle is generated: it is used
      * to prepend the banner file on the generated bundle.
@@ -57,6 +47,15 @@ module.exports = (options = {}) => {
      * @return {void}
      */
     renderChunk(code, chunk, outputOptions = {}) {
+      plugin.scanDependencies(
+          _.chain(chunk.modules)
+              .toPairs()
+              .reject((mod) => mod[1].isAsset)
+              .filter((mod) => mod[1].renderedLength > 0)
+              .map((mod) => mod[0])
+              .value()
+      );
+
       return plugin.prependBanner(code, outputOptions.sourcemap !== false);
     },
 
diff --git a/src/license-plugin.js b/src/license-plugin.js
index fffda227..333b5200 100644
--- a/src/license-plugin.js
+++ b/src/license-plugin.js
@@ -153,10 +153,10 @@ module.exports = class LicensePlugin {
     if (id.startsWith('\0')) {
       id = id.replace(/^\0/, '');
       this.debug(`scanning internal module ${id}`);
-    } else {
-      this.debug(`scanning ${id}`);
     }
 
+    this.debug(`scanning ${id}`);
+
     // Look for the `package.json` file
     let dir = path.parse(id).dir;
     let pkg = null;
@@ -202,6 +202,20 @@ module.exports = class LicensePlugin {
     });
   }
 
+  /**
+   * Hook triggered by `rollup` to load code from given path file.
+   *
+   * @param {Object} dependencies List of modules included in the final bundle.
+   * @return {void}
+   */
+  scanDependencies(dependencies) {
+    this.debug(`Scanning: ${dependencies}`);
+
+    _.forEach(dependencies, (dependency) => {
+      this.scanDependency(dependency);
+    });
+  }
+
   /**
    * Hook triggered by `rollup` to transform the final generated bundle.
    * This hook is used here to prepend the license banner to the final bundle.
diff --git a/test/index-rollup-stable.spec.js b/test/index-rollup-stable.spec.js
index f587e268..9de6d2fc 100644
--- a/test/index-rollup-stable.spec.js
+++ b/test/index-rollup-stable.spec.js
@@ -48,7 +48,7 @@ describe('rollup-plugin-license [rollup stable]', () => {
     expect(instance.name).toBe('rollup-plugin-license');
   });
 
-  it('should scan dependency on load', (done) => {
+  it('should scan dependencies when chunk is rendered', (done) => {
     const thirdPartyOutput = path.join(tmpDir.name, 'dependencies.txt');
     const instance = plugin({
       thirdParty: {
@@ -57,9 +57,21 @@ describe('rollup-plugin-license [rollup stable]', () => {
       },
     });
 
-    const id = path.join(__dirname, 'fixtures', 'fake-package', 'src', 'index.js');
+    const moduleId = path.join(__dirname, 'fixtures', 'fake-package', 'src', 'index.js');
+    const modules = {
+      [moduleId]: {
+        renderedExports: [],
+        removedExports: [],
+        renderedLength: 10,
+        originalLength: 100,
+      },
+    };
+
+    const code = 'var foo = 0;';
+    const chunk = {code, modules};
+    const outputOptions = {};
 
-    instance.load(id);
+    instance.renderChunk(code, chunk, outputOptions);
     instance.generateBundle();
 
     fs.readFile(thirdPartyOutput, 'utf8', (err, data) => {
@@ -105,7 +117,21 @@ describe('rollup-plugin-license [rollup stable]', () => {
       },
     });
 
-    instance.load('lodash');
+    const moduleId = path.join(__dirname, 'fixtures', 'fake-package', 'src', 'index.js');
+    const modules = {
+      [moduleId]: {
+        renderedExports: [],
+        removedExports: [],
+        renderedLength: 10,
+        originalLength: 100,
+      },
+    };
+
+    const code = 'var foo = 0;';
+    const chunk = {code, modules};
+    const outputOptions = {};
+
+    instance.renderChunk(code, chunk, outputOptions);
     instance.generateBundle();
 
     fs.readFile(thirdPartyOutput, 'utf8', (err, data) => {
diff --git a/test/license-plugin.spec.js b/test/license-plugin.spec.js
index 15d5a37b..ab9fb3ad 100644
--- a/test/license-plugin.spec.js
+++ b/test/license-plugin.spec.js
@@ -130,6 +130,35 @@ describe('LicensePlugin', () => {
     });
   });
 
+  it('should load pkg dependencies', () => {
+    const plugin = new LicensePlugin();
+    const modules = [
+      path.join(__dirname, 'fixtures', 'fake-package', 'src', 'index.js'),
+    ];
+
+    spyOn(plugin, 'scanDependency').and.callThrough();
+    spyOn(plugin, 'addDependency').and.callThrough();
+
+    const result = plugin.scanDependencies(modules);
+
+    expect(result).not.toBeDefined();
+    expect(plugin.scanDependency).toHaveBeenCalledWith(modules[0]);
+    expect(plugin.addDependency).toHaveBeenCalled();
+    expect(plugin._dependencies).toEqual({
+      'fake-package': {
+        name: 'fake-package',
+        version: '1.0.0',
+        description: 'Fake package used in unit tests',
+        license: 'MIT',
+        private: true,
+        author: {
+          name: 'Mickael Jeanroy',
+          email: 'mickael.jeanroy@gmail.com',
+        },
+      },
+    });
+  });
+
   it('should load pkg and stop on cwd', () => {
     const plugin = new LicensePlugin();
     const id = path.join(__dirname, '..', 'src', 'index.js');