diff --git a/core/includes/common.inc b/core/includes/common.inc
index e96ea9b..3e48fb3 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -5192,7 +5192,7 @@ function drupal_system_listing($mask, $directory, $key = 'name', $min_depth = 1)
     foreach (array_intersect_key($files_to_add, $files) as $file_key => $file) {
       // If it has no info file, then we just behave liberally and accept the
       // new resource on the list for merging.
-      if (file_exists($info_file = dirname($file->uri) . '/' . $file->name . '.yml')) {
+      if (file_exists($info_file = dirname($file->uri) . '/' . $file->name . '.info.yml')) {
         // Get the .info file for the module or theme this file belongs to.
         $info = drupal_parse_info_file($info_file);
 
@@ -6544,37 +6544,32 @@ function drupal_array_nested_key_exists(array $array, array $parents) {
  *
  * Info files are NOT for placing arbitrary theme and module-specific settings.
  * Use variable_get() and variable_set() for that. Info files are formatted as
- * YAML. If a key called "version" is set to "VERSION" in any info file, the PHP
- * constant of the same name will be substituted into the resulting data.
+ * YAML. If the 'version' key is set to 'VERSION' in any info file, then the
+ * value will be substituted with the current version of Drupal core.
  *
- * Information stored in a module .info file:
+ * Information stored in a module .info.yml file:
  * - name: The real name of the module for display purposes.
  * - description: A brief description of the module.
+ * - core: The version of Drupal core the module is compatible with.
  * - dependencies: An array of shortnames of other modules this module requires.
  * - package: The name of the package of modules this module belongs to.
  *
- * See forum.info for an example of a module .info file.
- *
- * Information stored in a theme .info file:
+ * Information stored in a theme .info.yml file:
  * - name: The real name of the theme for display purposes.
  * - description: Brief description.
- * - screenshot: Path to screenshot relative to the theme's .info file.
+ * - screenshot: Path to screenshot relative to the theme's .info.yml file.
  * - engine: Theme engine; typically phptemplate.
- * - base: Name of a base theme, if applicable
+ * - base theme: Name of a base theme, if applicable
  * - regions: Listed regions
  * - features: Features available
  * - stylesheets: Theme stylesheets
  * - scripts: Theme scripts
  *
- * See bartik.info for an example of a theme .info file.
- *
- * @param $filename
+ * @param string $filename
  *   The file we are parsing. Accepts file with relative or absolute path.
  *
- * @return
+ * @return array
  *   The info array.
- *
- * @see http://yaml.org/
  */
 function drupal_parse_info_file($filename) {
   $info = &drupal_static(__FUNCTION__, array());
@@ -6586,7 +6581,7 @@ function drupal_parse_info_file($filename) {
     else {
       $data = file_get_contents($filename);
       $info[$filename] = Yaml::parse($filename);
-      if (isset($info[$filename]['version']) && $info[$filename]['version'] == 'VERSION') {
+      if (isset($info[$filename]['version']) && $info[$filename]['version'] === 'VERSION') {
         $info[$filename]['version'] = VERSION;
       }
     }
diff --git a/core/includes/install.inc b/core/includes/install.inc
index f7cbcb0..fed5974 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -907,7 +907,7 @@ function install_profile_info($profile, $langcode = 'en') {
       'hidden' => FALSE,
       'php' => DRUPAL_MINIMUM_PHP,
     );
-    $profile_file = drupal_get_path('profile', $profile) . "/$profile.yml";
+    $profile_file = drupal_get_path('profile', $profile) . "/$profile.info.yml";
     $info = drupal_parse_info_file($profile_file);
     $info += $defaults;
     $info['dependencies'] = array_unique(array_merge(
diff --git a/core/includes/module.inc b/core/includes/module.inc
index ca3cb5d..dbac1a7 100644
--- a/core/includes/module.inc
+++ b/core/includes/module.inc
@@ -999,7 +999,7 @@ function module_invoke_all($hook) {
  * Returns an array of modules required by core.
  */
 function drupal_required_modules() {
-  $files = drupal_system_listing('/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.yml$/', 'modules', 'name', 0);
+  $files = drupal_system_listing('/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.info.yml$/', 'modules', 'name', 0);
   $required = array();
 
   // An installation profile is required and one must always be loaded.
diff --git a/core/lib/Drupal/Core/Updater/Updater.php b/core/lib/Drupal/Core/Updater/Updater.php
index 1fe2fcd..cdd4e4e 100644
--- a/core/lib/Drupal/Core/Updater/Updater.php
+++ b/core/lib/Drupal/Core/Updater/Updater.php
@@ -94,7 +94,7 @@ public static function getUpdaterFromDirectory($directory) {
    *   Path to the info file.
    */
   public static function findInfoFile($directory) {
-    $info_files = file_scan_directory($directory, '/.*\.yml$/');
+    $info_files = file_scan_directory($directory, '/.*\.info.yml$/');
     if (!$info_files) {
       return FALSE;
     }
diff --git a/core/modules/system/lib/Drupal/system/Tests/System/InfoFileParserUnitTest.php b/core/modules/system/lib/Drupal/system/Tests/System/InfoFileParserUnitTest.php
deleted file mode 100644
index dfa47d8..0000000
--- a/core/modules/system/lib/Drupal/system/Tests/System/InfoFileParserUnitTest.php
+++ /dev/null
@@ -1,84 +0,0 @@
-<?php
-
-/**
- * @file
- * Definition of Drupal\system\Tests\System\InfoFileParserUnitTest.
- */
-
-namespace Drupal\system\Tests\System;
-
-use Drupal\simpletest\UnitTestBase;
-
-class InfoFileParserUnitTest extends UnitTestBase {
-  public static function getInfo() {
-    return array(
-      'name' => 'Info file format parser',
-      'description' => 'Tests proper parsing of a .info file formatted string.',
-      'group' => 'System',
-    );
-  }
-
-  /**
-   * Test drupal_parse_info_format().
-   */
-  function testDrupalParseInfoFormat() {
-    $config = "
-simple: Value
-quoted: ' Value'
-array:
-  - Value1
-  - Value2
-array_assoc:
-  a: Value1
-  b: Value2
-array_deep:
-  - [[Value]]
-array_deep_assoc:
-  a:
-    b:
-      c: Value
-array_space:
-  'a b': Value";
-
-    $expected = array(
-      'simple' => 'Value',
-      'quoted' => ' Value',
-      'array' => array(
-        0 => 'Value1',
-        1 => 'Value2',
-      ),
-      'array_assoc' => array(
-        'a' => 'Value1',
-        'b' => 'Value2',
-      ),
-      'array_deep' => array(
-        0 => array(
-          0 => array(
-            0 => 'Value',
-          ),
-        ),
-      ),
-      'array_deep_assoc' => array(
-        'a' => array(
-          'b' => array(
-            'c' => 'Value',
-          ),
-        ),
-      ),
-      'array_space' => array(
-        'a b' => 'Value',
-      ),
-    );
-
-    $parsed = Yaml::parse($config);
-
-    $this->assertEqual($parsed['simple'], $expected['simple'], t('Set a simple value.'));
-    $this->assertEqual($parsed['quoted'], $expected['quoted'], t('Set a simple value in quotes.'));
-    $this->assertEqual($parsed['array'], $expected['array'], t('Set a simple array.'));
-    $this->assertEqual($parsed['array_assoc'], $expected['array_assoc'], t('Set an associative array.'));
-    $this->assertEqual($parsed['array_deep'], $expected['array_deep'], t('Set a nested array.'));
-    $this->assertEqual($parsed['array_deep_assoc'], $expected['array_deep_assoc'], t('Set a nested associative array.'));
-    $this->assertEqual($parsed['array_space'], $expected['array_space'], t('Set an array with a whitespace in the key.'));
-    $this->assertEqual($parsed, $expected, t('Entire parsed .info string and expected array are identical.'));
-  }
-}
diff --git a/core/modules/system/system.admin.inc b/core/modules/system/system.admin.inc
index 74db842..7ea9de5 100644
--- a/core/modules/system/system.admin.inc
+++ b/core/modules/system/system.admin.inc
@@ -1315,7 +1315,7 @@ function system_modules_uninstall_confirm_form($storage) {
 
   // Construct the hidden form elements and list items.
   foreach (array_filter($storage['uninstall']) as $module => $value) {
-    $info = drupal_parse_info_file(drupal_get_path('module', $module) . '/' . $module . '.yml');
+    $info = drupal_parse_info_file(drupal_get_path('module', $module) . '/' . $module . '.info.yml');
     $uninstall[] = $info['name'];
     $form['uninstall'][$module] = array('#type' => 'hidden',
       '#value' => 1,
diff --git a/core/modules/system/system.api.php b/core/modules/system/system.api.php
index c10a3b5..d824380 100644
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -1694,7 +1694,7 @@ function hook_system_theme_info() {
  *
  * This hook is invoked in _system_rebuild_module_data() and in
  * _system_rebuild_theme_data(). A module may implement this hook in order to
- * add to or alter the data generated by reading the .yml file with
+ * add to or alter the data generated by reading the .info.yml file with
  * drupal_parse_info_file().
  *
  * @param $info
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index abe7184..f686086 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -2756,11 +2756,11 @@ function _system_rebuild_module_data() {
     $modules[$key]->filename = $module->uri;
 
     // Look for the info file.
-    $module->info = drupal_parse_info_file(dirname($module->uri) . '/' . $module->name . '.yml');
+    $module->info = drupal_parse_info_file(dirname($module->uri) . '/' . $module->name . '.info.yml');
 
     // Add the info file modification time, so it becomes available for
     // contributed modules to use for ordering module lists.
-    $module->info['mtime'] = filemtime(dirname($module->uri) . '/' . $module->name . '.yml');
+    $module->info['mtime'] = filemtime(dirname($module->uri) . '/' . $module->name . '.info.yml');
 
     // Skip modules that don't provide info.
     if (empty($module->info)) {
@@ -2866,7 +2866,7 @@ function _system_update_bootstrap_status() {
  */
 function _system_rebuild_theme_data() {
   // Find themes
-  $themes = drupal_system_listing('/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.yml$/', 'themes');
+  $themes = drupal_system_listing('/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.info.yml$/', 'themes');
   // Allow modules to add further themes.
   if ($module_themes = module_invoke_all('system_theme_info')) {
     foreach ($module_themes as $name => $uri) {
diff --git a/core/modules/system/tests/common_test_info.txt b/core/modules/system/tests/common_test_info.txt
index caacf80d..ae217b9 100644
--- a/core/modules/system/tests/common_test_info.txt
+++ b/core/modules/system/tests/common_test_info.txt
@@ -1,10 +1,9 @@
----
-# Test parsing with a simple string.
-simple_string: A simple string
+; Test parsing with a simple string.
+simple_string = A simple string
 
-# Test that the VERSION constant substitution works
-version: VERSION
+; Test that constants can be used as values.
+simple_constant = WATCHDOG_INFO
 
-# After parsing the .info file, 'double_colon' should hold the literal value.
-# Parsing should not throw a fatal error or try to access a class constant.
-double_colon: dummyClassName::
+; After parsing the .info file, 'double_colon' should hold the literal value.
+; Parsing should not throw a fatal error or try to access a class constant.
+double_colon = dummyClassName::
diff --git a/core/modules/update/update.compare.inc b/core/modules/update/update.compare.inc
index 64ce974..2bacac4 100644
--- a/core/modules/update/update.compare.inc
+++ b/core/modules/update/update.compare.inc
@@ -149,15 +149,15 @@ function update_process_info_list(&$projects, $list, $project_type, $status, $ad
       continue;
     }
 
-    // If we don't already know it, grab the change time on the .yml file
+    // If we don't already know it, grab the change time on the .info.yml file
     // itself. Note: we need to use the ctime, not the mtime (modification
     // time) since many (all?) tar implementations will go out of their way to
     // set the mtime on the files it creates to the timestamps recorded in the
     // tarball. We want to see the last time the file was changed on disk,
-    // which is left alone by tar and correctly set to the time the .yml file
-    // was unpacked.
+    // which is left alone by tar and correctly set to the time the .info.yml
+    // file was unpacked.
     if (!isset($file->info['_info_file_ctime'])) {
-      $info_filename = dirname($file->uri) . '/' . $file->name . '.yml';
+      $info_filename = dirname($file->uri) . '/' . $file->name . '.info.yml';
       $file->info['_info_file_ctime'] = filectime($info_filename);
     }
 
@@ -809,13 +809,13 @@ function update_project_cache($cid) {
  * Filters the project .info data to only save attributes we need.
  *
  * @param array $info
- *   Array of .yml file data as returned by drupal_parse_info_file().
+ *   Array of .info.yml file data as returned by drupal_parse_info_file().
  * @param $additional_whitelist
  *   (optional) Array of additional elements to be collected from the .info
  *   file. Defaults to array().
  *
  * @return
- *   Array of .yml file data we need for the update manager.
+ *   Array of .info.yml file data we need for the update manager.
  *
  * @see update_process_info_list()
  */
diff --git a/core/modules/update/update.module b/core/modules/update/update.module
index b9e0e0b..1f45ce7 100644
--- a/core/modules/update/update.module
+++ b/core/modules/update/update.module
@@ -694,7 +694,7 @@ function update_verify_update_archive($project, $archive_file, $directory) {
   // functionality).
   $compatible_project = FALSE;
   $incompatible = array();
-  $files = file_scan_directory("$directory/$project", '/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.yml$/', array('key' => 'name', 'min_depth' => 0));
+  $files = file_scan_directory("$directory/$project", '/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.info.yml$/', array('key' => 'name', 'min_depth' => 0));
   foreach ($files as $key => $file) {
     // Get the .info file for the module or theme this file belongs to.
     $info = drupal_parse_info_file($file->uri);
diff --git a/core/scripts/convert-info-yml.php b/core/scripts/convert-info-yml.php
new file mode 100644
index 0000000..a5bfaed
--- /dev/null
+++ b/core/scripts/convert-info-yml.php
@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * @file
+ * Converts .info files into .info.yml files.
+ *
+ * Usage:
+ * @code
+ *   php core/scripts/convert-info-yml.php path/to/some.info [...]
+ * @endcode
+ */
+
+use Symfony\Component\Yaml\Yaml;
+
+// Customize if needed.
+$git_path = 'git';
+
+
+define('DRUPAL_ROOT', getcwd());
+
+require_once DRUPAL_ROOT . '/core/includes/bootstrap.inc';
+drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);
+
+$info_files = $_SERVER['argv'];
+array_shift($info_files);
+
+foreach ($info_files as $info_file) {
+  $info = file_get_contents($info_file);
+  $info = drupal_parse_info_format($info);
+  $yaml = Yaml::dump($info);
+  $yaml_file = $info_file . '.yml';
+  file_put_contents($yaml_file, $yaml);
+  system($git_path . ' rm ' . escapeshellarg($info_file));
+  system($git_path . ' add ' . escapeshellarg($yaml_file));
+}
+
+/**
+ * Parses data in Drupal's .info format.
+ *
+ * Data should be in an .ini-like format to specify values. White-space
+ * generally doesn't matter, except inside values:
+ * @code
+ *   key = value
+ *   key = "value"
+ *   key = 'value'
+ *   key = "multi-line
+ *   value"
+ *   key = 'multi-line
+ *   value'
+ *   key
+ *   =
+ *   'value'
+ * @endcode
+ *
+ * Arrays are created using a HTTP GET alike syntax:
+ * @code
+ *   key[] = "numeric array"
+ *   key[index] = "associative array"
+ *   key[index][] = "nested numeric array"
+ *   key[index][index] = "nested associative array"
+ * @endcode
+ *
+ * PHP constants are substituted in, but only when used as the entire value.
+ * Comments should start with a semi-colon at the beginning of a line.
+ *
+ * @param $data
+ *   A string to parse.
+ *
+ * @return
+ *   The info array.
+ *
+ * @see drupal_parse_info_file()
+ */
+function drupal_parse_info_format($data) {
+  $info = array();
+  $constants = get_defined_constants();
+
+  if (preg_match_all('
+    @^\s*                           # Start at the beginning of a line, ignoring leading whitespace
+    ((?:
+      [^=;\[\]]|                    # Key names cannot contain equal signs, semi-colons or square brackets,
+      \[[^\[\]]*\]                  # unless they are balanced and not nested
+    )+?)
+    \s*=\s*                         # Key/value pairs are separated by equal signs (ignoring white-space)
+    (?:
+      ("(?:[^"]|(?<=\\\\)")*")|     # Double-quoted string, which may contain slash-escaped quotes/slashes
+      (\'(?:[^\']|(?<=\\\\)\')*\')| # Single-quoted string, which may contain slash-escaped quotes/slashes
+      ([^\r\n]*?)                   # Non-quoted string
+    )\s*$                           # Stop at the next end of a line, ignoring trailing whitespace
+    @msx', $data, $matches, PREG_SET_ORDER)) {
+    foreach ($matches as $match) {
+      // Fetch the key and value string.
+      $i = 0;
+      foreach (array('key', 'value1', 'value2', 'value3') as $var) {
+        $$var = isset($match[++$i]) ? $match[$i] : '';
+      }
+      $value = stripslashes(substr($value1, 1, -1)) . stripslashes(substr($value2, 1, -1)) . $value3;
+
+      // Parse array syntax.
+      $keys = preg_split('/\]?\[/', rtrim($key, ']'));
+      $last = array_pop($keys);
+      $parent = &$info;
+
+      // Create nested arrays.
+      foreach ($keys as $key) {
+        if ($key == '') {
+          $key = count($parent);
+        }
+        if (!isset($parent[$key]) || !is_array($parent[$key])) {
+          $parent[$key] = array();
+        }
+        $parent = &$parent[$key];
+      }
+
+      // Handle PHP constants.
+      // Note: All constants except VERSION are converted to their actual values.
+      if ($value !== 'VERSION' && isset($constants[$value])) {
+        $value = $constants[$value];
+      }
+
+      // Insert actual value.
+      if ($last == '') {
+        $last = count($parent);
+      }
+      $parent[$last] = $value;
+    }
+  }
+
+  return $info;
+}