refactor: extract parseGitZOutput util

lib/getStagedFiles.js

@@ -3,6 +3,7 @@ import path from 'path'
 import normalize from 'normalize-path'
 
 import { execGit } from './execGit.js'
+import { parseGitZOutput } from './parseGitZOutput.js'
 
 export const getStagedFiles = async ({ cwd = process.cwd() } = {}) => {
   try {
@@ -14,15 +15,7 @@ export const getStagedFiles = async ({ cwd = process.cwd() } = {}) => {
 
     if (!lines) return []
 
-    // With `-z`, git prints `fileA\u0000fileB\u0000fileC\u0000` so we need to
-    // remove the last occurrence of `\u0000` before splitting
-    return (
-      lines
-        // eslint-disable-next-line no-control-regex
-        .replace(/\u0000$/, '')
-        .split('\u0000')
-        .map((file) => normalize(path.resolve(cwd, file)))
-    )
+    return parseGitZOutput(lines).map((file) => normalize(path.resolve(cwd, file)))
   } catch {
     return null
   }

lib/parseGitZOutput.js

@@ -0,0 +1,9 @@
+/**
+ * Return array of strings split from the output of `git <something> -z`.
+ * With `-z`, git prints `fileA\u0000fileB\u0000fileC\u0000` so we need to
+ * remove the last occurrence of `\u0000` before splitting
+ */
+export const parseGitZOutput = (input) =>
+  input
+    .replace(/\u0000$/, '') // eslint-disable-line no-control-regex
+    .split('\u0000')

lib/searchConfigs.js

@@ -6,6 +6,7 @@ import normalize from 'normalize-path'
 
 import { execGit } from './execGit.js'
 import { loadConfig, searchPlaces } from './loadConfig.js'
+import { parseGitZOutput } from './parseGitZOutput.js'
 import { validateConfig } from './validateConfig.js'
 
 const EXEC_GIT = ['ls-files', '-z', '--full-name']
@@ -25,20 +26,14 @@ const sortDeepestParth = (a, b) => (numberOfLevels(a) > numberOfLevels(b) ? -1 :
  */
 export const searchConfigs = async (gitDir = process.cwd(), logger) => {
   /** Get all possible config files known to git */
-  const cachedFiles = (await execGit(EXEC_GIT, { cwd: gitDir }))
-    // eslint-disable-next-line no-control-regex
-    .replace(/\u0000$/, '')
-    .split('\u0000')
-    .filter(filterPossibleConfigFiles)
+  const cachedFiles = parseGitZOutput(await execGit(EXEC_GIT, { cwd: gitDir })).filter(
+    filterPossibleConfigFiles
+  )
 
   /** Get all possible config files from uncommitted files */
-  const otherFiles = (
+  const otherFiles = parseGitZOutput(
     await execGit([...EXEC_GIT, '--others', '--exclude-standard'], { cwd: gitDir })
-  )
-    // eslint-disable-next-line no-control-regex
-    .replace(/\u0000$/, '')
-    .split('\u0000')
-    .filter(filterPossibleConfigFiles)
+  ).filter(filterPossibleConfigFiles)
 
   /** Sort possible config files so that deepest is first */
   const possibleConfigFiles = [...cachedFiles, ...otherFiles]

test/parseGitZOutput.spec.js

@@ -0,0 +1,13 @@
+import { parseGitZOutput } from '../lib/parseGitZOutput'
+
+describe('parseGitZOutput', () => {
+  it('should split string from `git -z` control character', () => {
+    const input = 'a\u0000b\u0000c'
+    expect(parseGitZOutput(input)).toEqual(['a', 'b', 'c'])
+  })
+
+  it('should remove trailing `git -z` control character', () => {
+    const input = 'a\u0000'
+    expect(parseGitZOutput(input)).toEqual(['a'])
+  })
+})