feat: support multiple --env-file arguments

actions/generate.action.ts

@@ -20,6 +20,12 @@ import {
 } from '../lib/utils/project-utils';
 import { AbstractAction } from './abstract.action';
 
+function assertNonArray<T>(value: T): asserts value is Exclude<T, any[]> {
+  if (Array.isArray(value)) {
+    throw new TypeError('Expected a non-array value');
+  }
+}
+
 export class GenerateAction extends AbstractAction {
   public async handle(inputs: Input[], options: Input[]) {
     await generateFiles(inputs.concat(options));
@@ -153,6 +159,7 @@ const mapSchematicOptions = (inputs: Input[]): SchematicOption[] => {
   const options: SchematicOption[] = [];
   inputs.forEach((input) => {
     if (!excludedInputNames.includes(input.name) && input.value !== undefined) {
+      assertNonArray(input.value);
       options.push(new SchematicOption(input.name, input.value));
     }
   });

actions/new.action.ts

@@ -65,6 +65,12 @@ export class NewAction extends AbstractAction {
   }
 }
 
+function assertNonArray<T>(value: T): asserts value is Exclude<T, any[]> {
+  if (Array.isArray(value)) {
+    throw new TypeError('Expected a non-array value');
+  }
+}
+
 const getApplicationNameInput = (inputs: Input[]) =>
   inputs.find((input) => input.name === 'name');
 
@@ -133,6 +139,7 @@ const mapSchematicOptions = (options: Input[]): SchematicOption[] => {
   return options.reduce(
     (schematicOptions: SchematicOption[], option: Input) => {
       if (option.name !== 'skip-install') {
+        assertNonArray(option.value);
         schematicOptions.push(new SchematicOption(option.name, option.value));
       }
       return schematicOptions;

actions/start.action.ts

@@ -14,6 +14,12 @@ import { ERROR_PREFIX } from '../lib/ui';
 import { treeKillSync as killProcessSync } from '../lib/utils/tree-kill';
 import { BuildAction } from './build.action';
 
+function assertNonArray<T>(value: T): asserts value is Exclude<T, any[]> {
+  if (Array.isArray(value)) {
+    throw new TypeError('Expected a non-array value');
+  }
+}
+
 export class StartAction extends BuildAction {
   public async handle(commandInputs: Input[], commandOptions: Input[]) {
     try {
@@ -44,6 +50,8 @@ export class StartAction extends BuildAction {
         watchAssetsModeOption && watchAssetsModeOption.value
       );
       const debugFlag = debugModeOption && debugModeOption.value;
+      assertNonArray(debugFlag);
+
       const binaryToRun = getValueOrDefault(
         configuration,
         'exec',
@@ -81,7 +89,7 @@ export class StartAction extends BuildAction {
       const envFileOption = commandOptions.find(
         (option) => option.name === 'envFile',
       );
-      const envFile = envFileOption?.value as string;
+      const envFile = (envFileOption?.value ?? []) as string[];
 
       const onSuccess = this.createOnSuccessHook(
         entryFile,
@@ -120,7 +128,7 @@ export class StartAction extends BuildAction {
     binaryToRun: string,
     options: {
       shell: boolean;
-      envFile?: string;
+      envFile?: string[];
     },
   ) {
     let childProcessRef: any;
@@ -177,7 +185,7 @@ export class StartAction extends BuildAction {
     binaryToRun: string,
     options: {
       shell: boolean;
-      envFile?: string;
+      envFile?: string[];
     },
   ) {
     let outputFilePath = join(outDirName, sourceRoot, entryFile);
@@ -206,9 +214,14 @@ export class StartAction extends BuildAction {
         typeof debug === 'string' ? `--inspect=${debug}` : '--inspect';
       processArgs.unshift(inspectFlag);
     }
-    if (options.envFile) {
-      processArgs.unshift(`--env-file=${options.envFile}`);
+
+    if (options.envFile && options.envFile.length > 0) {
+      const envFileNodeArgs = options.envFile.map(
+        (envFilePath) => `--env-file=${envFilePath}`,
+      );
+      processArgs.unshift(envFileNodeArgs.join(' '));
     }
+
     processArgs.unshift('--enable-source-maps');
 
     return spawn(binaryToRun, processArgs, {

commands/command.input.ts

@@ -1,5 +1,5 @@
 export interface Input {
   name: string;
-  value: boolean | string;
+  value: boolean | string | string[];
   options?: any;
 }

commands/start.command.ts

@@ -6,6 +6,10 @@ import { Input } from './command.input';
 
 export class StartCommand extends AbstractCommand {
   public load(program: CommanderStatic): void {
+    const collect = (value: any, previous: any) => {
+      return previous.concat([value]);
+    };
+
     program
       .command('start [app]')
       .allowUnknownOption()
@@ -47,6 +51,8 @@ export class StartCommand extends AbstractCommand {
       .option(
         '--env-file [path]',
         'Path to an env file (.env) to be loaded into the environment.',
+        collect,
+        [],
       )
       .description('Run Nest application.')
       .action(async (app: string, command: Command) => {