feat: allow --reporter to be relative to CWD (#24)

* test: pass --reporter values relative to CWD

This test ensures that a --reporter value can be passed with a path
relative to the CWD.

The test should fail with this error:

      1) Commands
          should accept custom reporters relative to the current working directory:
        Command failed: /Users/spencerelliott/Dev/elliottsj/webpack-command/lib/cli.js --reporter ../../lib/reporters/BasicReporter /Users/spencerelliott/Dev/elliottsj/webpack-command/test/fixtures/flags/config/src
    TypeError: ReporterClass is not a constructor
        at module.exports (/Users/spencerelliott/Dev/elliottsj/webpack-command/lib/compiler.js:91:20)
        at load.then (/Users/spencerelliott/Dev/elliottsj/webpack-command/lib/index.js:45:47)
        at process._tickCallback (internal/process/next_tick.js:68:7)
        at Function.Module.runMain (internal/modules/cjs/loader.js:746:11)
        at startup (internal/bootstrap/node.js:238:19)
        at bootstrapNodeJSCore (internal/bootstrap/node.js:572:3)

* feat: allow --reporter to be relative to CWD

Previously, the --reporter path must have been either absolute or in
node_modules or relative to lib/compiler.js.

This change ensures that a path passed to --reporter is resolved relative
to process.cwd().

e.g. you can now run this inside of a project directory to use a custom
reporter:

    webpack --reporter ./MyCustomReporter.js

* refactor: loop rather than nest. makes for a little better readability

* fix: exit the loop if reporter was found

* fix: remove whitespace leftover from github editor

lib/compiler.js

@@ -1,3 +1,5 @@
+const path = require('path');
+
 const camelcase = require('camelcase');
 const capitalize = require('titleize');
 const chalk = require('chalk');
@@ -36,23 +38,28 @@ function makeCallback(options) {
 /**
  * Attempts to require a specified reporter. Tries the local built-ins first,
  * and if that fails, attempts to load an npm module that exports a reporter
- * handler function.
+ * handler function, and if that fails, attempts to load the reporter relative
+ * to the current working directory.
  */
-function requireReporter(name, local = true) {
+function requireReporter(name) {
   const prefix = capitalize(camelcase(name));
-  const target = local ? `./reporters/${prefix}Reporter` : name;
-
-  try {
-    // eslint-disable-next-line import/no-dynamic-require, global-require
-    const result = require(target);
-    return result;
-  } catch (e) {
-    if (local) {
-      return requireReporter(name, false);
+  const locations = [`./reporters/${prefix}Reporter`, name, path.resolve(name)];
+  let result = null;
+
+  for (const location of locations) {
+    try {
+      // eslint-disable-next-line import/no-dynamic-require, global-require
+      result = require(location);
+    } catch (e) {
+      // noop
     }
 
-    return null;
+    if (result) {
+      break;
+    }
   }
+
+  return result;
 }
 
 /**

test/tests/__snapshots__/cli.js.snap

@@ -1,5 +1,22 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`Commands > should accept custom reporters relative to the current working directory #0 1`] = `
+"ℹ ｢webpack｣: Starting Build
+ℹ ｢webpack｣: Build Finished
+Hash: 953ce188d35af8c002f0
+<version>
+<duration>
+<datetime>
+  Asset       Size  Chunks             Chunk Names
+main.js  573 bytes       0  [emitted]  main
+Entrypoint main = main.js
+[0] ../fixtures/flags/config/src/index.js 43 bytes {0} [built]
+
+WARNING in configuration
+The 'mode' option has not been set, webpack will fallback to 'production' for this value. Set 'mode' option to 'development' or 'production' to enable defaults for each environment.
+You can also set it to 'none' to disable any default behavior. Learn more: https://webpack.js.org/concepts/mode/"
+`;
+
 exports[`Commands > should add directories to entries #0 1`] = `
 "ℹ ｢webpack｣: Starting Build
 ℹ ｢webpack｣: Build Finished

test/tests/cli.js

@@ -79,4 +79,23 @@ test('Commands', module, () => {
       strip(result.stdout).replace(/Δt \d+ms/g, '<duration>')
     ).toMatchSnapshot();
   }).timeout(4000);
+
+  it('should accept custom reporters relative to the current working directory', () => {
+    const cliPath = resolve(__dirname, '../../lib/cli.js');
+    const srcPath = resolve(__dirname, '../../test/fixtures/flags/config/src');
+    const result = execa.sync(
+      cliPath,
+      ['--reporter', '../../lib/reporters/BasicReporter', srcPath],
+      {
+        cwd: __dirname,
+      }
+    );
+
+    expect(
+      strip(result.stdout)
+        .replace(/Version: webpack \d\.\d\.\d/, '<version>')
+        .replace(/Time: \d+ms/g, '<duration>')
+        .replace(/Built at: .+(?=\n)/g, '<datetime>')
+    ).toMatchSnapshot();
+  }).timeout(4000);
 });