From e5126f10b6622437c0541c25be2a610a82c1df04 Mon Sep 17 00:00:00 2001
From: Nitin Kumar <snitin315@gmail.com>
Date: Tue, 2 Feb 2021 20:59:51 +0530
Subject: [PATCH] feat: add the `--node-env` flag (#2388)

---
 packages/webpack-cli/lib/webpack-cli.js | 16 +++++++-
 test/node-env/auto-mode.config.js       |  5 +++
 test/node-env/node-env.test.js          | 53 +++++++++++++++++++++++++
 test/node-env/src/index.js              |  1 +
 test/node-env/webpack.config.js         |  6 +++
 5 files changed, 80 insertions(+), 1 deletion(-)
 create mode 100644 test/node-env/auto-mode.config.js
 create mode 100644 test/node-env/node-env.test.js
 create mode 100644 test/node-env/src/index.js
 create mode 100644 test/node-env/webpack.config.js

diff --git a/packages/webpack-cli/lib/webpack-cli.js b/packages/webpack-cli/lib/webpack-cli.js
index 79f7070534c..15be68263dc 100644
--- a/packages/webpack-cli/lib/webpack-cli.js
+++ b/packages/webpack-cli/lib/webpack-cli.js
@@ -295,6 +295,12 @@ class WebpackCLI {
                 multiple: true,
                 description: 'Environment passed to the configuration when it is a function.',
             },
+            {
+                name: 'node-env',
+                type: String,
+                multiple: false,
+                description: 'Sets process.env.NODE_ENV to the specified value',
+            },
 
             // Adding more plugins
             {
@@ -429,6 +435,12 @@ class WebpackCLI {
         return options;
     }
 
+    applyNodeEnv(options) {
+        if (typeof options.nodeEnv === 'string') {
+            process.env.NODE_ENV = options.nodeEnv;
+        }
+    }
+
     async run(args, parseOptions) {
         // Built-in internal commands
         const buildCommandOptions = {
@@ -1517,7 +1529,7 @@ class WebpackCLI {
                 !configOptions.mode &&
                 process.env &&
                 process.env.NODE_ENV &&
-                (process.env.NODE_ENV === 'development' || process.env.NODE_ENV === 'production' || process.env.NODE_ENV === 'node')
+                (process.env.NODE_ENV === 'development' || process.env.NODE_ENV === 'production' || process.env.NODE_ENV === 'none')
             ) {
                 configOptions.mode = process.env.NODE_ENV;
             }
@@ -1653,6 +1665,8 @@ class WebpackCLI {
     }
 
     async createCompiler(options, callback) {
+        this.applyNodeEnv(options);
+
         let config = await this.resolveConfig(options);
 
         config = await this.applyOptions(config, options);
diff --git a/test/node-env/auto-mode.config.js b/test/node-env/auto-mode.config.js
new file mode 100644
index 00000000000..385cb2ac035
--- /dev/null
+++ b/test/node-env/auto-mode.config.js
@@ -0,0 +1,5 @@
+const WebpackCLITestPlugin = require('../utils/webpack-cli-test-plugin');
+
+module.exports = {
+    plugins: [new WebpackCLITestPlugin()],
+};
diff --git a/test/node-env/node-env.test.js b/test/node-env/node-env.test.js
new file mode 100644
index 00000000000..4d8bda5d328
--- /dev/null
+++ b/test/node-env/node-env.test.js
@@ -0,0 +1,53 @@
+'use strict';
+
+const { run } = require('../utils/test-utils');
+
+describe('--node-env flag', () => {
+    it('should set "process.env.NODE_ENV" to "development"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'development']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'development'");
+    });
+
+    it('should set "process.env.NODE_ENV" to "production"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'production']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'production'");
+    });
+
+    it('should set "process.env.NODE_ENV" to "none"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'none']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'none'");
+    });
+
+    it('should set "process.env.NODE_ENV" and the "mode" option to "development"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'development', '--config', './auto-mode.config.js']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'development'");
+    });
+
+    it('should set "process.env.NODE_ENV" and the "mode" option to "production"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'production', '--config', './auto-mode.config.js']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'production'");
+    });
+
+    it('should set "process.env.NODE_ENV" and the "mode" option to "none"', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['--node-env', 'none', '--config', './auto-mode.config.js']);
+
+        expect(exitCode).toBe(0);
+        expect(stderr).toBeFalsy();
+        expect(stdout).toContain("mode: 'none'");
+    });
+});
diff --git a/test/node-env/src/index.js b/test/node-env/src/index.js
new file mode 100644
index 00000000000..c70a2899e94
--- /dev/null
+++ b/test/node-env/src/index.js
@@ -0,0 +1 @@
+console.log('--node-env test');
\ No newline at end of file
diff --git a/test/node-env/webpack.config.js b/test/node-env/webpack.config.js
new file mode 100644
index 00000000000..ca74229899d
--- /dev/null
+++ b/test/node-env/webpack.config.js
@@ -0,0 +1,6 @@
+const WebpackCLITestPlugin = require('../utils/webpack-cli-test-plugin');
+
+module.exports = {
+    mode: process.env.NODE_ENV,
+    plugins: [new WebpackCLITestPlugin()],
+};