Add Git version control engine

commands/pm/download.pm.inc

@@ -212,6 +212,16 @@ function drush_pm_download() {
       $skip_list = array('.', '..');
       $skip_list = array_merge($skip_list, drush_version_control_reserved_files());
       drush_scan_directory($request['project_install_location'], '/.*/', $skip_list, 'unlink', TRUE, 'filename', 0, TRUE);
+
+      // If the version control engine is a proper vcs we also need to remove
+      // orphan directories.
+      if ($version_control->engine != 'backup') {
+        $empty_dirs = drush_find_empty_directories($request['full_project_path'], $version_control->reserved_files());
+        foreach ($empty_dirs as $empty_dir) {
+          // Some VCS files are read-only on Windows (e.g., .svn/entries).
+          drush_delete_dir($empty_dir, TRUE);
+        }
+      }
     }
 
     // Copy the project to the install location.

commands/pm/pm.drush.inc

@@ -1802,6 +1802,27 @@ function pm_drush_engine_version_control() {
         'drush [command] cck --svncommitparams=\"--username joe\"' =>  'Commit changes as the user \'joe\' (Quotes are required).'
       ),
     ),
+    'git' => array(
+      'signature' => 'git status %s',
+      'description' => 'Quickly add/remove/commit your project changes to Git.',
+      'options' => array(
+        'gitsync' => 'Automatically add new files to the Git repository and remove deleted files. Caution.',
+        'gitcommit' => 'Automatically commit changes to Git repository. Implies the --gitsync option.',
+      ),
+      'sub-options' => array(
+        'gitcommit' => array(
+          'gitmessage' => 'Override default commit message which is: Drush automatic commit: <the drush command line used>',
+          'gitcommitparams' => 'Add options to the `git commit` command',
+        ),
+        'gitsync' => array(
+          'gitaddparams' => 'Add options to the `git add` command',
+        ),
+      ),
+      'examples' => array(
+        'drush dl --gitcommit ctools' =>  'Download the ctools module and commit the changes.',
+        'drush [command] ctools --gitcommit --gitcommitparams=\"--author joe\"' =>  'Commit changes as the user \'joe\' (Quotes are required).'
+      ),
+    ),
   );
 }
 

commands/pm/updatecode.pm.inc

@@ -346,6 +346,13 @@ function pm_update_project($project, $version_control) {
     $skip_list = array('.', '..');
     $skip_list = array_merge($skip_list, drush_version_control_reserved_files());
     drush_scan_directory($project['full_project_path'], '/.*/', $skip_list, 'unlink', TRUE, 'filename', 0, TRUE);
+
+    // If the version control engine is a proper vcs we also need to remove
+    // orphan directories.
+    if (($version_control->engine != 'backup') && (drush_get_option('package-handler', 'wget') == 'wget')) {
+      $files = drush_find_empty_directories($project['full_project_path'], $version_control->reserved_files());
+      array_map('drush_delete_dir', $files);
+    }
   }
 
   // Add the project to a context so we can roll back if needed.

commands/pm/version_control/git.inc

@@ -0,0 +1,94 @@
+<?php
+
+/**
+ * @file
+ * Drush pm GIT extension
+ */
+
+class drush_version_control_git implements drush_version_control {
+
+  /**
+   * Implementation of pre_update().
+   */
+  public function pre_update(&$project, $items_to_test = array()) {
+
+    // No-op. Nothing to do here.
+    return TRUE;
+  }
+
+  /**
+   * Implementation of rollback().
+   */
+  public function rollback($project) {
+    // TODO, do we need this at all?
+    // Other VCS implementations do a revert ... but can we trust that a commit was made?
+  }
+
+  /**
+   * Implementation of post_update().
+   */
+  public function post_update($project) {
+    if ($this->sync($project)) {
+      // Only attempt commit on a sucessful sync
+      $this->commit($project);
+    }
+  }
+
+  /**
+   * Implementation of post_download().
+   */
+  public function post_download($project) {
+    if ($this->sync($project)) {
+      // Only attempt commit on a sucessful sync
+      $this->commit($project);
+    }
+  }
+
+  /**
+   * Automatically add any unversioned files to Git and remove any files
+   * that have been deleted on the file system in the full_project_path.
+   */
+  private function sync($project) {
+    if (drush_get_option('gitsync') || drush_get_option('gitcommit')) {
+      $errors = '';
+      if (!drush_shell_exec('git add --all '. drush_get_option('gitaddparams') .' '. $project['full_project_path'])) {
+        $errors .= implode("\n", drush_shell_exec_output());
+      }
+      if (!empty($errors)) {
+        return drush_set_error('DRUSH_PM_GIT_SYNC_PROBLEMS', dt("Problems were encountered adding or removing files to/from this GIT working copy.\nThe specific errors are below:\n!errors", array('!errors' => $errors)));
+      }
+      return TRUE;
+    }
+  }
+
+  /**
+   * Automatically commit changes to the repository
+   */
+  private function commit($project) {
+    if (drush_get_option('gitcommit')) {
+      $message = drush_get_option('gitmessage');
+      if (empty($message)) {
+        $from = '';
+        if (!empty($project['existing_version'])) {
+          $from = "from $project[existing_version] ";
+        }
+        $version = !empty($project['version']) ? $project['version'] : $project['recommended'];
+        $message = dt("Update $project[name] ${from}to $version");
+      }
+      if (drush_shell_exec('git commit '. drush_get_option('gitcommitparams') .' -m '. escapeshellarg($message))) {
+        drush_log(dt('Project !name committed to Git successfully', array('!name' => $project['name'])), 'ok');
+      }
+      else {
+        drush_set_error('DRUSH_PM_GIT_COMMIT_PROBLEMS', dt("Problems were encountered committing your changes to Git.\nThe specific errors are below:\n!errors", array('!errors' => implode("\n", drush_shell_exec_output()))));
+      }
+    }
+    else {
+      drush_print(dt("You should consider committing the new code to your Git repository.\nIf this version becomes undesireable, use Git to roll back."));
+    }
+  }
+
+  public static function reserved_files() {
+    // .gitignore is not in this list as it can be safely committed to a project.
+    return array('.git');
+  }
+}

includes/drush.inc

@@ -1705,7 +1705,7 @@ function drush_version_control_reserved_files() {
 
   if (!$files) {
     // Also support VCSs that are not drush vc engines.
-    $files = array('.git', '.gitignore', '.hg', '.hgignore', '.hgrags');
+    $files = array('.hg', '.hgignore', '.hgrags');
     $engine_info = drush_get_engines('version_control');
     $vcs = array_keys($engine_info['engines']);
     foreach ($vcs as $name) {