feat(cli): Added cli-config-file option. (#20)

This PR add a new option that can point to JSON file. This file can contain any option supported by CLI (either in `kebab-case` or `camelCase` format) and will applied accordingly.
Other options explicitly provided via command line override the one in the JSON file (so that the file can act as a "template").

Fixes swc-project/cli#284.

Author: ShogunPanda

.changeset/slimy-cameras-jog.md

@@ -0,0 +1,5 @@
+---
+"@swc/cli": patch
+---
+
+feat(cli): Added cli-config-file option.

packages/cli/package.json

@@ -47,7 +47,7 @@
     "dependencies": {
         "@mole-inc/bin-wrapper": "^8.0.1",
         "@swc/counter": "workspace:^",
-        "commander": "^7.1.0",
+        "commander": "^8.3.0",
         "fast-glob": "^3.2.5",
         "minimatch": "^9.0.3",
         "piscina": "^4.3.0",

packages/cli/src/spack/options.ts

@@ -9,25 +9,26 @@ export interface SpackCliOptions {
     debug: boolean;
 }
 
-commander.option("--config [path]", "Path to a spack.config.js file to use.");
+const program = new commander.Command();
+program.option("--config [path]", "Path to a spack.config.js file to use.");
 // TODO: allow using ts. See: https://github.com/swc-project/swc/issues/841
 
-commander.option("--mode <development | production | none>", "Mode to use");
-commander.option("--target [browser | node]", "Target runtime environment");
+program.option("--mode <development | production | none>", "Mode to use");
+program.option("--target [browser | node]", "Target runtime environment");
 
-commander.option(
+program.option(
     "--context [path]",
     `The base directory (absolute path!) for resolving the 'entry'` +
         ` option. If 'output.pathinfo' is set, the included pathinfo is shortened to this directory`,
     "The current directory"
 );
 
-commander.option("--entry [list]", "List of entries", collect);
+program.option("--entry [list]", "List of entries", collect);
 
-// commander.option('-W --watch', `Enter watch mode, which rebuilds on file change.`)
+// program.option('-W --watch', `Enter watch mode, which rebuilds on file change.`)
 
-commander.option("--debug", `Switch loaders to debug mode`);
-// commander.option('--devtool', `Select a developer tool to enhance debugging.`)
+program.option("--debug", `Switch loaders to debug mode`);
+// program.option('--devtool', `Select a developer tool to enhance debugging.`)
 
 // -d           shortcut for --debug --devtool eval-cheap-module-source-map
 //              --output-pathinfo                                          [여부]
@@ -40,11 +41,11 @@ commander.option("--debug", `Switch loaders to debug mode`);
 // --module-bind-pre   Bind an extension to a pre loader                 [문자열]
 
 // Output options:
-commander.option(
+program.option(
     "-o --output",
     `The output path and file for compilation assets`
 );
-commander.option("--output-path", `The output directory as **absolute path**`);
+program.option("--output-path", `The output directory as **absolute path**`);
 //   --output-filename             Specifies the name of each output file on disk.
 //                                 You must **not** specify an absolute path here!
 //                                 The `output.path` option determines the location
@@ -158,7 +159,7 @@ commander.option("--output-path", `The output directory as **absolute path**`);
 //   --silent       Prevent output from being displayed in stdout         [boolean]
 //   --json, -j     Prints the result as JSON.                            [boolean]
 
-commander.version(
+program.version(
     `@swc/cli: ${pkg.version}
 @swc/core: ${swcCoreVersion}`
 );
@@ -168,7 +169,7 @@ export default async function parseSpackArgs(args: string[]): Promise<{
     spackOptions: BundleOptions;
 }> {
     //
-    const cmd = commander.parse(args);
+    const cmd = program.parse(args);
     const opts = cmd.opts();
 
     const cliOptions: SpackCliOptions = {

packages/cli/src/swc/__mocks__/fs.ts

@@ -3,22 +3,34 @@ import type { Stats } from "fs";
 
 export interface MockHelpers {
     resetMockStats: () => void;
+    resetMockFiles: () => void;
     setMockStats: (stats: Record<string, Stats | Error>) => void;
+    setMockFile: (path: string, contents: string) => void;
 }
 
 const fsMock = jest.createMockFromModule<typeof fs & MockHelpers>("fs");
 
 let mockStats: Record<string, Stats | Error> = {};
+let mockFiles: Record<string, string> = {};
 
 function setMockStats(stats: Record<string, Stats | Error>) {
     Object.entries(stats).forEach(([path, stats]) => {
         mockStats[path] = stats;
     });
 }
+
+function setMockFile(path: string, contents: string) {
+    mockFiles[path] = contents;
+}
+
 function resetMockStats() {
     mockStats = {};
 }
 
+function resetMockFiles() {
+    mockFiles = {};
+}
+
 export function stat(path: string, cb: (err?: Error, stats?: Stats) => void) {
     const result = mockStats[path];
     if (result instanceof Error) {
@@ -28,9 +40,21 @@ export function stat(path: string, cb: (err?: Error, stats?: Stats) => void) {
     }
 }
 
+export function readFileSync(path: string): string {
+    if (!mockFiles[path]) {
+        throw new Error("Non existent.");
+    }
+
+    return mockFiles[path];
+}
+
 fsMock.setMockStats = setMockStats;
 fsMock.resetMockStats = resetMockStats;
 
+fsMock.setMockFile = setMockFile;
+fsMock.resetMockFiles = resetMockFiles;
+
 fsMock.stat = stat as typeof fs.stat;
+fsMock.readFileSync = readFileSync as typeof fs.readFileSync;
 
 export default fsMock;

packages/cli/src/swc/__tests__/options.test.ts

@@ -1,5 +1,9 @@
 import type { Options } from "@swc/core";
 import deepmerge from "deepmerge";
+import fs from "fs";
+import { resolve } from "path";
+
+jest.mock("fs");
 
 import parserArgs, { CliOptions, initProgram } from "../options";
 
@@ -56,6 +60,7 @@ describe("parserArgs", () => {
     beforeEach(() => {
         defaultResult = createDefaultResult();
         initProgram();
+        (fs as any).resetMockFiles();
     });
 
     it("minimal args returns default result", async () => {
@@ -91,7 +96,7 @@ describe("parserArgs", () => {
                 "src",
             ];
             const result = parserArgs(args);
-            expect(result.cliOptions.outFileExtension).toEqual("js");
+            expect(result!.cliOptions.outFileExtension).toEqual("js");
         });
     });
 
@@ -270,7 +275,7 @@ describe("parserArgs", () => {
             const expectedOptions = deepmerge(defaultResult.swcOptions, {
                 jsc: { transform: { react: { development: true } } },
             });
-            expect(result.swcOptions).toEqual(expectedOptions);
+            expect(result!.swcOptions).toEqual(expectedOptions);
         });
 
         it("react development and commonjs (two config options)", async () => {
@@ -288,7 +293,7 @@ describe("parserArgs", () => {
                 jsc: { transform: { react: { development: true } } },
                 module: { type: "commonjs" },
             });
-            expect(result.swcOptions).toEqual(expectedOptions);
+            expect(result!.swcOptions).toEqual(expectedOptions);
         });
 
         it("react development and commonjs (comma-separated)", async () => {
@@ -304,7 +309,7 @@ describe("parserArgs", () => {
                 jsc: { transform: { react: { development: true } } },
                 module: { type: "commonjs" },
             });
-            expect(result.swcOptions).toEqual(expectedOptions);
+            expect(result!.swcOptions).toEqual(expectedOptions);
         });
 
         it("no equals sign", async () => {
@@ -319,7 +324,110 @@ describe("parserArgs", () => {
             const expectedOptions = deepmerge(defaultResult.swcOptions, {
                 no_equals: true,
             });
-            expect(result.swcOptions).toEqual(expectedOptions);
+            expect(result!.swcOptions).toEqual(expectedOptions);
+        });
+    });
+
+    describe("--cli-config-file", () => {
+        it("reads a JSON config file with both camel and kebab case options", async () => {
+            (fs as any).setMockFile(
+                resolve(process.cwd(), "/swc/cli.json"),
+                JSON.stringify({
+                    outFileExtension: "mjs",
+                    deleteDirOnStart: "invalid",
+                    "delete-dir-on-start": true,
+                })
+            );
+
+            const args = [
+                "node",
+                "/path/to/node_modules/swc-cli/bin/swc.js",
+                "src",
+                "--cli-config-file",
+                "/swc/cli.json",
+            ];
+            const result = parserArgs(args);
+            const expectedOptions = deepmerge(defaultResult, {
+                cliOptions: { outFileExtension: "mjs", deleteDirOnStart: true },
+            });
+
+            expect(result).toEqual(expectedOptions);
+        });
+
+        it("reads a JSON but options are overriden from CLI", async () => {
+            (fs as any).setMockFile(
+                resolve(process.cwd(), "/swc/cli.json"),
+                JSON.stringify({
+                    outFileExtension: "mjs",
+                    "delete-dir-on-start": true,
+                })
+            );
+
+            const args = [
+                "node",
+                "/path/to/node_modules/swc-cli/bin/swc.js",
+                "src",
+                "--cli-config-file",
+                "/swc/cli.json",
+                "--out-file-extension",
+                "cjs",
+            ];
+            const result = parserArgs(args);
+            const expectedOptions = deepmerge(defaultResult, {
+                cliOptions: { outFileExtension: "cjs", deleteDirOnStart: true },
+            });
+
+            expect(result).toEqual(expectedOptions);
+        });
+
+        describe("exits", () => {
+            let mockExit: jest.SpyInstance;
+            let mockConsoleError: jest.SpyInstance;
+
+            beforeEach(() => {
+                mockExit = jest
+                    .spyOn(process, "exit")
+                    // @ts-expect-error
+                    .mockImplementation(() => {});
+                mockConsoleError = jest
+                    .spyOn(console, "error")
+                    .mockImplementation(() => {});
+            });
+
+            afterEach(() => {
+                mockExit.mockRestore();
+                mockConsoleError.mockRestore();
+            });
+
+            it("if the config file is missing", async () => {
+                const args = [
+                    "node",
+                    "/path/to/node_modules/swc-cli/bin/swc.js",
+                    "src",
+                    "--cli-config-file",
+                    "/swc/cli.json",
+                ];
+
+                parserArgs(args);
+                expect(mockExit).toHaveBeenCalledWith(2);
+                expect(mockConsoleError).toHaveBeenCalledTimes(2);
+            });
+
+            it("if the config file is not valid JSON", async () => {
+                (fs as any).setMockFile("/swc/cli.json", "INVALID");
+
+                const args = [
+                    "node",
+                    "/path/to/node_modules/swc-cli/bin/swc.js",
+                    "src",
+                    "--cli-config-file",
+                    "/swc/cli.json",
+                ];
+
+                parserArgs(args);
+                expect(mockExit).toHaveBeenCalledWith(2);
+                expect(mockConsoleError).toHaveBeenCalledTimes(2);
+            });
         });
     });
 });