fix: restore original state when preventing an empty commit

lib/gitWorkflow.js

@@ -125,7 +125,7 @@ class GitWorkflow {
       debug('Backing up original state...')
 
       const unstagedPatch = this.getHiddenFilepath(PATCH_UNSTAGED)
-      await this.execGit(['diff', ...GIT_DIFF_ARGS, '--output', unstagedPatch, '--', '.'])
+      await this.execGit(['diff', ...GIT_DIFF_ARGS, '--output', unstagedPatch])
 
       // Get a list of files with bot staged and unstaged changes.
       // Unstaged changes to these files should be hidden before the tasks run.
@@ -162,23 +162,6 @@ class GitWorkflow {
     }
   }
 
-  /**
-   * Restore original HEAD state in case of errors
-   */
-  async restoreOriginalState(ctx) {
-    try {
-      debug('Restoring original state...')
-      await this.execGit(['checkout', '--force', '--', '.'])
-
-      const unstagedPatch = this.getHiddenFilepath(PATCH_UNSTAGED)
-      await this.execGit(['apply', ...GIT_APPLY_ARGS, unstagedPatch])
-
-      debug('Done restoring original state!')
-    } catch (error) {
-      handleError(error, ctx, RestoreOriginalStateError)
-    }
-  }
-
   /** Add all task modifications to index for files that were staged before running. */
   async applyModifications(ctx) {
     debug('Adding task modifications to index...')
@@ -203,6 +186,23 @@ class GitWorkflow {
     debug('Done adding task modifications to index!')
   }
 
+  /**
+   * Restore original HEAD state in case of errors
+   */
+  async restoreOriginalState(ctx) {
+    try {
+      debug('Restoring original state...')
+      await this.execGit(['checkout', '--force', '--', '.'])
+
+      const unstagedPatch = this.getHiddenFilepath(PATCH_UNSTAGED)
+      await this.execGit(['apply', ...GIT_APPLY_ARGS, unstagedPatch])
+
+      debug('Done restoring original state!')
+    } catch (error) {
+      handleError(error, ctx, RestoreOriginalStateError)
+    }
+  }
+
   /**
    * Restore unstaged changes to partially changed files. If it at first fails,
    * this is probably because of conflicts between new task modifications.

lib/state.js

@@ -45,7 +45,15 @@ const restorePartialChangesSkipped = (ctx) => {
   }
 }
 
-const restoreOriginalStateEnabled = (ctx) => ctx.shouldBackup && ctx.errors.has(TaskError)
+const restoreOriginalStateEnabled = (ctx) => {
+  if (ctx.shouldBackup && ctx.errors.has(TaskError)) {
+    return TASK_ERROR
+  }
+
+  if (ctx.errors.has(ApplyEmptyCommitError)) {
+    return true
+  }
+}
 
 const restoreOriginalStateSkipped = (ctx) => {
   // Should be skipped in case of unknown git errors

test/integration.test.js

@@ -149,6 +149,19 @@ describe('lint-staged', () => {
     expect(await readFile('test2.js')).toEqual(testJsFilePretty)
   })
 
+  it('Should warn when task contains deprecated `git add`', async () => {
+    // Stage ugly file
+    await appendFile('test.js', testJsFileUgly)
+    await execGit(['add', 'test.js'])
+
+    // Run lint-staged with `prettier --write` and commit pretty file
+    await gitCommit({ config: { '*.js': ['prettier --write', 'git add'] } })
+
+    expect(console.printHistory()).toMatch(
+      'Some of your tasks use `git add` command. Please remove it from the config since all modifications made by tasks will be automatically added to the git commit index.'
+    )
+  })
+
   it('Should fail to commit entire staged file when errors from linter', async () => {
     // Stage ugly file
     await appendFile('test.js', testJsFileUgly)
@@ -664,27 +677,24 @@ describe('lint-staged', () => {
 
     // Run lint-staged with prettier --write to automatically fix the file
     // Since prettier reverts all changes, the commit should fail
-    // use the old syntax with manual `git add` to provide a warning message
     await expect(
-      gitCommit({ config: { '*.js': ['prettier --write', 'git add'] } })
+      gitCommit({ config: { '*.js': ['prettier --write'] } })
     ).rejects.toThrowErrorMatchingInlineSnapshot(`"lint-staged failed"`)
 
     expect(console.printHistory()).toMatchInlineSnapshot(`
       "
-      WARN ⚠ Some of your tasks use \`git add\` command. Please remove it from the config since all modifications made by tasks will be automatically added to the git commit index.
-
       LOG [STARTED] Preparing...
       LOG [SUCCESS] Preparing...
       LOG [STARTED] Running tasks...
       LOG [STARTED] Running tasks for *.js
       LOG [STARTED] prettier --write
       LOG [SUCCESS] prettier --write
-      LOG [STARTED] git add
-      LOG [SUCCESS] git add
       LOG [SUCCESS] Running tasks for *.js
       LOG [SUCCESS] Running tasks...
       LOG [STARTED] Applying modifications...
       ERROR [FAILED] Prevented an empty git commit!
+      LOG [STARTED] Reverting because of errors...
+      ERROR [FAILED] error: unrecognized input
       LOG [STARTED] Cleaning up...
       LOG [SUCCESS] Cleaning up...
       WARN