feat: allow specifying a custom location for config files (#122)

Fixes #121

README.md

@@ -128,9 +128,14 @@ export a JS object with your config. Any file starting with `bulk-decaffeinate`
 and ending with `.config.js` will be counted, and multiple config files may
 exist at once. If there are multiple config files, they are merged, with
 alphabetically-later config file names taking precedence over
-alphabetically-earlier files. Many config options can also be specified
-directly as CLI arguments, with CLI arguments taking precedence over any config
-file setting.
+alphabetically-earlier files.
+
+Alternatively, you may specify the config file location using the `--config`
+option, e.g. `bulk-decaffeinate --config ../bulk-decaffeinate.config.js` to use
+a config file one level up in the directory structure.
+
+Many config options can also be specified directly as CLI arguments, with CLI
+arguments taking precedence over any config file setting.
 
 Here's an example config file:
 

src/cli.js

@@ -24,37 +24,42 @@ export default function () {
            of its subdirectories.
     land: Create a merge commit with all commits generated by bulk-decaffeinate.`)
     .action(commandArg => command = commandArg)
+    .option('-c, --config [path]',
+      `The config file to use. This arg may be specified multiple
+                              times. If unspecified, files like bulk-decaffeinate.config.js will
+                              be discovered and used.`,
+      (arg, args) => {args.push(arg); return args;}, [])
     .option('-f, --file [path]',
       `An absolute or relative path to decaffeinate. This arg may be
-                            specified multiple times.`,
+                              specified multiple times.`,
       (arg, args) => {args.push(arg); return args;}, [])
     .option('-p, --path-file [path]',
       `A file containing the paths of .coffee files to decaffeinate, one
-                            path per line. Paths can be either absolute or relative to the
-                            current working directory.`)
+                              path per line. Paths can be either absolute or relative to the
+                              current working directory.`)
     .option('-d, --dir [path]',
       `A directory containing files to decaffeinate. All .coffee files in
-                            any subdirectory of this directory are considered for decaffeinate.`)
+                              any subdirectory of this directory are considered for decaffeinate.`)
     .option('--allow-invalid-constructors',
       `If specified, the --allow-invalid-constructors arg is added when
-                            invoking decaffeinate.`)
+                              invoking decaffeinate.`)
     .option('--land-base [revision]',
       `The git revision to use as the base commit when running the "land"
-                            command. If none is specified, bulk-decaffeinate tries to use the
-                            first auto-generated commit in recent history.`)
+                              command. If none is specified, bulk-decaffeinate tries to use the
+                              first auto-generated commit in recent history.`)
     .option('--skip-verify',
       `If specified, skips the initial verification step when running the
-                            "convert" command.`)
+                              "convert" command.`)
     .option('--decaffeinate-path [path]',
       `The path to the decaffeinate binary. If none is specified, it will
-                            be automatically discovered from node_modules and then from the
-                            PATH.`)
+                              be automatically discovered from node_modules and then from the
+                              PATH.`)
     .option('--jscodeshift-path [path]',
       `The path to the jscodeshift binary. If none is specified, it will be
-                            automatically discovered from node_modules and then from the PATH.`)
+                              automatically discovered from node_modules and then from the PATH.`)
     .option('--eslint-path [path]',
       `The path to the eslint binary. If none is specified, it will be
-                            automatically discovered from node_modules and then from the PATH.`)
+                              automatically discovered from node_modules and then from the PATH.`)
     .parse(process.argv);
 
   runCommand(command);

src/config/resolveConfig.js

@@ -14,10 +14,16 @@ import execLive from '../util/execLive';
 export default async function resolveConfig(commander) {
   let config = {};
 
-  let currentDirFiles = await readdir('.');
-  currentDirFiles.sort();
-  for (let filename of currentDirFiles) {
-    config = await applyPossibleConfig(filename, config);
+  if (commander.config && commander.config.length > 0) {
+    for (let filename of commander.config) {
+      config = applyConfig(filename, config);
+    }
+  } else {
+    let currentDirFiles = await readdir('.');
+    currentDirFiles.sort();
+    for (let filename of currentDirFiles) {
+      config = await applyPossibleConfig(filename, config);
+    }
   }
   config = getCLIParamsConfig(config, commander);
   return {
@@ -47,20 +53,24 @@ async function applyPossibleConfig(filename, config) {
     return config;
   }
 
-  let filePath = resolve(filename);
   if (filename.endsWith('.config.js')) {
-    try {
-      let newConfig = requireUncached(filePath);
-      return Object.assign(config, newConfig);
-    } catch (e) {
-      throw new CLIError(
-        `Error reading file ${filePath}. Make sure it is a valid JS file.`);
-    }
+    return applyConfig(filename, config);
   } else {
     return config;
   }
 }
 
+function applyConfig(filename, config) {
+  let filePath = resolve(filename);
+  try {
+    let newConfig = requireUncached(filePath);
+    return Object.assign(config, newConfig);
+  } catch (e) {
+    throw new CLIError(
+      `Error reading file ${filePath}. Make sure it is a valid JS file.`);
+  }
+}
+
 /**
  * Fill in a configuration from the CLI arguments.
  */

test/bulk-decaffeinate-test.js

@@ -3,9 +3,12 @@ import assert from 'assert';
 import { readFile } from 'mz/fs';
 
 import {
+  assertFileContents,
   assertFileIncludes,
   assertIncludes,
+  initGitRepo,
   runCli,
+  runCliExpectSuccess,
   runWithTemplateDir,
 } from './test-util';
 
@@ -18,6 +21,25 @@ describe('basic CLI', () => {
   });
 });
 
+describe('config', () => {
+  it('allows explicitly-specified config files', async function() {
+    await runWithTemplateDir('custom-config-location', async function() {
+      await initGitRepo();
+      await runCliExpectSuccess(
+        'convert --config configDir1/config.js --config configDir2/otherConfig.js');
+      await assertFileContents('./A.ts', `\
+/* Automatically-added prefix. */
+/* eslint-disable
+    no-unused-vars,
+*/
+// TODO: This file was created by bulk-decaffeinate.
+// Fix any style issues and re-enable lint.
+const A = 1;
+`);
+    });
+  });
+});
+
 describe('check', () => {
   it('discovers and runs files', async function() {
     let {stdout} = await runCli('check -d test/examples/simple-success');

test/convert-test.js

@@ -10,18 +10,12 @@ import {
   assertIncludes,
   initGitRepo,
   runCli,
+  runCliExpectSuccess,
   runCliExpectError,
   runWithTemplateDir,
 } from './test-util';
 
 describe('convert', () => {
-  async function runCliExpectSuccess(command) {
-    let {stdout, stderr} = await runCli(command);
-    assert(stderr.length === 0, `Nonempty stderr. stderr:\n${stderr}\n\nstdout:\n${stdout}`);
-    assertIncludes(stdout, 'Successfully ran decaffeinate');
-    return {stdout, stderr};
-  }
-
   it('generates git commits converting the files', async function() {
     await runWithTemplateDir('simple-success', async function() {
       await initGitRepo();

test/examples/custom-config-location/A.coffee

@@ -0,0 +1 @@
+A = 1

test/examples/custom-config-location/configDir1/config.js

@@ -0,0 +1,3 @@
+module.exports = {
+  codePrefix: '/* Automatically-added prefix. */\n',
+};

test/examples/custom-config-location/configDir2/otherConfig.js

@@ -0,0 +1,3 @@
+module.exports = {
+  outputFileExtension: 'ts',
+};

test/test-util.js

@@ -16,6 +16,13 @@ export async function runCli(args) {
   return {stdout, stderr};
 }
 
+export async function runCliExpectSuccess(command) {
+  let {stdout, stderr} = await runCli(command);
+  assert(stderr.length === 0, `Nonempty stderr. stderr:\n${stderr}\n\nstdout:\n${stdout}`);
+  assertIncludes(stdout, 'Successfully ran decaffeinate');
+  return {stdout, stderr};
+}
+
 export async function runCliExpectError(args) {
   try {
     await runCli(args);