feat: --no-restage flag for skipping re-stage step in staged mode (#39)…

… (#40)

README.md

@@ -76,6 +76,10 @@ Pre-commit mode. Under this flag only staged files will be formatted, and they w
 
 Partially staged files will not be re-staged after formatting and pretty-quick will exit with a non-zero exit code. The intent is to abort the git commit and allow the user to amend their selective staging to include formatting fixes.
 
+### `--no-restage` (only git)
+
+Use with the `--staged` flag to skip re-staging files after formatting.
+
 ### `--branch`
 
 When not in `staged` pre-commit mode, use this flag to compare changes with the specified branch. Defaults to `master` (git) / `default` (hg) branch.

src/__tests__/scm-git.test.js

@@ -174,7 +174,23 @@ describe('with git', () => {
     expect(execa.sync).toHaveBeenCalledWith('git', ['add', './raz.js'], {
       cwd: '/',
     });
-    expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './foo.md'], {
+    expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './foo.js'], {
+      cwd: '/',
+    });
+    expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './bar.md'], {
+      cwd: '/',
+    });
+  });
+
+  test('with --staged AND --no-restage does not re-stage any files', () => {
+    mockGitFs();
+
+    prettyQuick('root', { since: 'banana', staged: true, restage: false });
+
+    expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './raz.js'], {
+      cwd: '/',
+    });
+    expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './foo.js'], {
       cwd: '/',
     });
     expect(execa.sync).not.toHaveBeenCalledWith('git', ['add', './bar.md'], {

src/index.js

@@ -9,6 +9,7 @@ export default (
     config,
     since,
     staged,
+    restage = true,
     branch,
     onFoundSinceRevision,
     onFoundChangedFiles,
@@ -46,7 +47,7 @@ export default (
     config,
     onWriteFile: file => {
       onWriteFile && onWriteFile(file);
-      if (staged) {
+      if (staged && restage) {
         if (wasFullyStaged(file)) {
           scm.stageFile(directory, file);
         } else {