Add support for yaml config file (#105)

* Add support for yaml config file

* add documentation

README.md

@@ -126,6 +126,33 @@ Here are the available reporters:
 * `dot`: outputs the test results in a compact format, where each passing test is represented by a ., and each failing test is represented by a X.
 * `junit`: outputs test results in a jUnit XML format
 
+## Config File Support
+
+A limited set of options may be specified via a configuration file. The
+configuration file is expected to be in the process's working directory, and
+named either `.borp.yaml` or `.borp.yml`; it may also be specified by
+defining the environment variable `BORP_CONF_FILE` and setting it to the
+full path to some yaml file.
+
+The current supported options are:
+
++ `files` (string[]): An array of test files to include. Globs are supported.
++ `reporters` (string[]): An array of reporters to use. May be relative path
+strings, or module name strings.
+
+### Example
+
+```yaml
+files:
+  - 'test/one.test.js'
+  - 'test/foo/*.test.js'
+
+reporters:
+  - './test/lib/my-reporter.js'
+  - spec
+  - '@reporters/silent'
+```
+
 ## License
 
 MIT

borp.js

@@ -15,13 +15,19 @@ import { checkCoverages } from 'c8/lib/commands/check-coverage.js'
 import os from 'node:os'
 import { execa } from 'execa'
 import { pathToFileURL } from 'node:url'
+import loadConfig from './lib/conf.js'
 
 /* c8 ignore next 4 */
 process.on('unhandledRejection', (err) => {
   console.error(err)
   process.exit(1)
 })
 
+const foundConfig = await loadConfig()
+if (foundConfig.length > 0) {
+  Array.prototype.push.apply(process.argv, foundConfig)
+}
+
 const args = parseArgs({
   args: process.argv.slice(2),
   options: {

fixtures/conf/glob-files.yaml

@@ -0,0 +1,3 @@
+files:
+  - 'test1/*.test.js'
+  - 'test2/**/*.test.js'

fixtures/conf/relative-reporter.yaml

@@ -0,0 +1,2 @@
+reporters:
+  - './reporter.js'

fixtures/conf/reporters.yaml

@@ -0,0 +1,3 @@
+reporters:
+  - spec
+  - '@reporters/silent'

lib/conf.js

@@ -0,0 +1,80 @@
+import { cwd } from 'node:process'
+import { open, readFile } from 'node:fs/promises'
+import { join } from 'node:path'
+import YAML from 'yaml'
+
+async function readYamlFile () {
+  let target
+  let fd
+  if (process.env.BORP_CONF_FILE) {
+    target = process.env.BORP_CONF_FILE
+    try {
+      fd = await open(target, 'r')
+    } catch {
+      return
+    }
+  } else {
+    const CWD = cwd()
+    try {
+      target = join(CWD, '.borp.yaml')
+      fd = await open(target, 'r')
+    } catch {
+      target = join(CWD, '.borp.yml')
+      try {
+        fd = await open(target, 'r')
+      } catch {
+        // Neither file is available. If we had an application logger that writes
+        // to stderr, we'd log an error message. But, as it is, we will just
+        // assume that all errors are "file does not exist.""
+        return
+      }
+    }
+  }
+
+  let fileData
+  try {
+    fileData = await readFile(fd, { encoding: 'utf8' })
+  } catch {
+    // Same thing as noted above. Skip it.
+    return
+  } finally {
+    await fd.close()
+  }
+
+  return fileData
+}
+
+async function loadConfig () {
+  const result = []
+  const fileData = await readYamlFile()
+  if (typeof fileData !== 'string') {
+    return result
+  }
+
+  let options
+  try {
+    options = YAML.parse(fileData)
+  } catch {
+    // We just don't care.
+    return result
+  }
+
+  if (options.reporters) {
+    for (const reporter of options.reporters) {
+      result.push('--reporter')
+      result.push(reporter)
+    }
+  }
+
+  // Append files AFTER all other supported config keys. The runner expects
+  // them as positional parameters.
+  if (options.files) {
+    for (const file of options.files) {
+      result.push(file)
+    }
+  }
+
+  return result
+}
+
+export default loadConfig

package.json

@@ -35,6 +35,7 @@
     "c8": "^10.0.0",
     "execa": "^9.3.0",
     "find-up": "^7.0.0",
-    "glob": "^10.3.10"
+    "glob": "^10.3.10",
+    "yaml": "^2.5.1"
   }
 }

test/config.test.js

@@ -0,0 +1,45 @@
+import { test } from 'node:test'
+import { execa } from 'execa'
+import { join } from 'desm'
+import { strictEqual } from 'node:assert'
+import path from 'node:path'
+
+const borp = join(import.meta.url, '..', 'borp.js')
+const confFilesDir = join(import.meta.url, '..', 'fixtures', 'conf')
+
+test('reporter from node_modules', async () => {
+  const cwd = join(import.meta.url, '..', 'fixtures', 'ts-esm')
+  const { stdout } = await execa('node', [borp], {
+    cwd,
+    env: {
+      BORP_CONF_FILE: path.join(confFilesDir, 'reporters.yaml')
+    }
+  })
+
+  strictEqual(stdout.indexOf('tests 2') >= 0, true)
+})
+
+test('reporter from relative path', async () => {
+  const cwd = join(import.meta.url, '..', 'fixtures', 'relative-reporter')
+  const { stdout } = await execa('node', [borp], {
+    cwd,
+    env: {
+      BORP_CONF_FILE: path.join(confFilesDir, 'relative-reporter.yaml')
+    }
+  })
+
+  strictEqual(/passed:.+add\.test\.js/.test(stdout), true)
+  strictEqual(/passed:.+add2\.test\.js/.test(stdout), true)
+})
+
+test('interprets globs for files', async () => {
+  const cwd = join(import.meta.url, '..', 'fixtures', 'files-glob')
+  const { stdout } = await execa('node', [borp], {
+    cwd,
+    env: {
+      BORP_CONF_FILE: path.join(confFilesDir, 'glob-files.yaml')
+    }
+  })
+
+  strictEqual(stdout.indexOf('tests 2') >= 0, true)
+})