Issue #2313917 by tedbow, pwolanin, jhedstrom, Wim Leers, Mixologic, larowlan, Mile23, Gábor Hojtsy, xjm, Berdir: Core version key in module's .info.yml doesn't respect core semantic versioning

core/includes/update.inc

@@ -58,8 +58,7 @@ function update_check_incompatibility($name, $type = 'module') {
     $file = $themes[$name];
   }
   if (!isset($file)
-      || !isset($file->info['core'])
-      || $file->info['core'] != \Drupal::CORE_COMPATIBILITY
+      || $file->info['core_incompatible']
       || version_compare(phpversion(), $file->info['php']) < 0) {
     return TRUE;
   }

core/lib/Drupal/Core/Extension/InfoParserDynamic.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\Core\Extension;
 
+use Composer\Semver\Semver;
 use Drupal\Component\Serialization\Exception\InvalidDataTypeException;
 use Drupal\Core\Serialization\Yaml;
 
@@ -10,6 +11,34 @@ use Drupal\Core\Serialization\Yaml;
  */
 class InfoParserDynamic implements InfoParserInterface {
 
+  /**
+   * The earliest Drupal version that supports the 'core_version_requirement'.
+   */
+  const FIRST_CORE_VERSION_REQUIREMENT_SUPPORTED_VERSION = '8.7.7';
+
+  /**
+   * Determines if a version satisfies the given constraints.
+   *
+   * This method uses \Composer\Semver\Semver::satisfies() but returns FALSE if
+   * the version or constraints are not valid instead of throwing an exception.
+   *
+   * @param string $version
+   *   The version.
+   * @param string $constraints
+   *   The constraints.
+   *
+   * @return bool
+   *   TRUE if the version satisfies the constraints, otherwise FALSE.
+   */
+  protected static function satisfies($version, $constraints) {
+    try {
+      return Semver::satisfies($version, $constraints);
+    }
+    catch (\UnexpectedValueException $exception) {
+      return FALSE;
+    }
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -28,6 +57,45 @@ class InfoParserDynamic implements InfoParserInterface {
       if (!empty($missing_keys)) {
         throw new InfoParserException('Missing required keys (' . implode(', ', $missing_keys) . ') in ' . $filename);
       }
+      if ($parsed_info['type'] === 'profile' && isset($parsed_info['core_version_requirement'])) {
+        // @todo Support the 'core_version_requirement' key in profiles in
+        //   https://www.drupal.org/node/3070401.
+        throw new InfoParserException("The 'core_version_requirement' key is not supported in profiles in $filename");
+      }
+      if (!isset($parsed_info['core']) && !isset($parsed_info['core_version_requirement'])) {
+        throw new InfoParserException("The 'core' or the 'core_version_requirement' key must be present in " . $filename);
+      }
+      if (isset($parsed_info['core']) && !preg_match("/^\d\.x$/", $parsed_info['core'])) {
+        throw new InfoParserException("Invalid 'core' value \"{$parsed_info['core']}\" in " . $filename);
+      }
+      if (isset($parsed_info['core_version_requirement'])) {
+        $supports_pre_core_version_requirement_version = static::isConstraintSatisfiedByPreviousVersion($parsed_info['core_version_requirement'], static::FIRST_CORE_VERSION_REQUIREMENT_SUPPORTED_VERSION);
+        // If the 'core_version_requirement' constraint does not satisfy any
+        // Drupal 8 versions before 8.7.7 then 'core' cannot be set or it will
+        // effectively support all versions of Drupal 8 because
+        // 'core_version_requirement' will be ignored in previous versions.
+        if (!$supports_pre_core_version_requirement_version && isset($parsed_info['core'])) {
+          throw new InfoParserException("The 'core_version_requirement' constraint ({$parsed_info['core_version_requirement']}) requires the 'core' key not be set in " . $filename);
+        }
+        // 'core_version_requirement' can not be used to specify Drupal 8
+        // versions before 8.7.7 because these versions do not use the
+        // 'core_version_requirement' key. Do not throw the exception if the
+        // constraint also is satisfied by 8.0.0-alpha1 to allow constraints
+        // such as '^8' or '^8 || ^9'.
+        if ($supports_pre_core_version_requirement_version && !static::satisfies('8.0.0-alpha1', $parsed_info['core_version_requirement'])) {
+          throw new InfoParserException("The 'core_version_requirement' can not be used to specify compatibility for a specific version before " . static::FIRST_CORE_VERSION_REQUIREMENT_SUPPORTED_VERSION . " in $filename");
+        }
+      }
+
+      // Determine if the extension is compatible with the current version of
+      // Drupal core.
+      try {
+        $core_version_constraint = isset($parsed_info['core_version_requirement']) ? $parsed_info['core_version_requirement'] : $parsed_info['core'];
+        $parsed_info['core_incompatible'] = !static::satisfies(\Drupal::VERSION, $core_version_constraint);
+      }
+      catch (\UnexpectedValueException $exception) {
+        $parsed_info['core_incompatible'] = TRUE;
+      }
       if (isset($parsed_info['version']) && $parsed_info['version'] === 'VERSION') {
         $parsed_info['version'] = \Drupal::VERSION;
       }
@@ -60,7 +128,80 @@ class InfoParserDynamic implements InfoParserInterface {
    *   An array of required keys.
    */
   protected function getRequiredKeys() {
-    return ['type', 'core', 'name'];
+    return ['type', 'name'];
+  }
+
+  /**
+   * Determines if a constraint is satisfied by earlier versions of Drupal 8.
+   *
+   * @param string $constraint
+   *   A core semantic version constraint.
+   * @param string $version
+   *   A core version.
+   *
+   * @return bool
+   *   TRUE if the constraint is satisfied by a core version prior to the
+   *   provided version.
+   */
+  protected static function isConstraintSatisfiedByPreviousVersion($constraint, $version) {
+    static $evaluated_constraints = [];
+    // Any particular constraint and version combination only needs to be
+    // evaluated once.
+    if (!isset($evaluated_constraints[$constraint][$version])) {
+      $evaluated_constraints[$constraint][$version] = FALSE;
+      foreach (static::getAllPreviousCoreVersions($version) as $previous_version) {
+        if (static::satisfies($previous_version, $constraint)) {
+          $evaluated_constraints[$constraint][$version] = TRUE;
+          // The constraint only has to satisfy one previous version so break
+          // when the first one is found.
+          break;
+        }
+      }
+    }
+    return $evaluated_constraints[$constraint][$version];
+  }
+
+  /**
+   * Gets all the versions of Drupal 8 before a specific version.
+   *
+   * @param string $version
+   *   The version to get versions before.
+   *
+   * @return array
+   *   All of the applicable Drupal 8 releases.
+   */
+  protected static function getAllPreviousCoreVersions($version) {
+    static $versions_lists = [];
+    // Check if list of previous versions for the specified version has already
+    // been created.
+    if (empty($versions_lists[$version])) {
+      // Loop through all minor versions including 8.7.
+      foreach (range(0, 7) as $minor) {
+        // The largest patch number in a release was 17 in 8.6.17. Use 27 to
+        // leave room for future security releases.
+        foreach (range(0, 27) as $patch) {
+          $patch_version = "8.$minor.$patch";
+          if ($patch_version === $version) {
+            // Reverse the order of the versions so that they will be evaluated
+            // from the most recent versions first.
+            $versions_lists[$version] = array_reverse($versions_lists[$version]);
+            return $versions_lists[$version];
+          }
+          if ($patch === 0) {
+            // If this is a '0' patch release like '8.1.0' first create the
+            // pre-release versions such as '8.1.0-alpha1' and '8.1.0-rc1'.
+            foreach (['alpha', 'beta', 'rc'] as $prerelease) {
+              // The largest prerelease number was  in 8.0.0-beta16.
+              foreach (range(0, 16) as $prerelease_number) {
+                $versions_lists[$version][] = "$patch_version-$prerelease$prerelease_number";
+              }
+            }
+          }
+          $versions_lists[$version][] = $patch_version;
+        }
+      }
+    }
+    return $versions_lists[$version];
   }
 
 }

core/lib/Drupal/Core/Extension/ModuleInstaller.php

@@ -81,9 +81,14 @@ class ModuleInstaller implements ModuleInstallerInterface {
    */
   public function install(array $module_list, $enable_dependencies = TRUE) {
     $extension_config = \Drupal::configFactory()->getEditable('core.extension');
+    // Get all module data so we can find dependencies and sort.
+    $module_data = system_rebuild_module_data();
+    foreach ($module_list as $module) {
+      if (!empty($module_data[$module]->info['core_incompatible'])) {
+        throw new MissingDependencyException("Unable to install modules: module '$module' is incompatible with this version of Drupal core.");
+      }
+    }
     if ($enable_dependencies) {
-      // Get all module data so we can find dependencies and sort.
-      $module_data = system_rebuild_module_data();
       $module_list = $module_list ? array_combine($module_list, $module_list) : [];
       if ($missing_modules = array_diff_key($module_list, $module_data)) {
         // One or more of the given modules doesn't exist.
@@ -108,6 +113,9 @@ class ModuleInstaller implements ModuleInstallerInterface {
 
           // Skip already installed modules.
           if (!isset($module_list[$dependency]) && !isset($installed_modules[$dependency])) {
+            if ($module_data[$dependency]->info['core_incompatible']) {
+              throw new MissingDependencyException("Unable to install modules: module '$module'. Its dependency module '$dependency' is incompatible with this version of Drupal core.");
+            }
             $module_list[$dependency] = $dependency;
           }
         }

core/modules/system/src/Controller/SystemController.php

@@ -222,8 +222,6 @@ class SystemController extends ControllerBase {
       }
 
       if (empty($theme->status)) {
-        // Ensure this theme is compatible with this version of core.
-        $theme->incompatible_core = !isset($theme->info['core']) || ($theme->info['core'] != \DRUPAL::CORE_COMPATIBILITY);
         // Require the 'content' region to make sure the main page
         // content has a common place in all themes.
         $theme->incompatible_region = !isset($theme->info['regions']['content']);
@@ -234,7 +232,7 @@ class SystemController extends ControllerBase {
         $theme->incompatible_engine = isset($theme->info['engine']) && !isset($theme->owner);
       }
       $theme->operations = [];
-      if (!empty($theme->status) || !$theme->incompatible_core && !$theme->incompatible_php && !$theme->incompatible_base && !$theme->incompatible_engine) {
+      if (!empty($theme->status) || !$theme->info['core_incompatible'] && !$theme->incompatible_php && !$theme->incompatible_base && !$theme->incompatible_engine) {
         // Create the operations links.
         $query['theme'] = $theme->getName();
         if ($this->themeAccess->checkAccess($theme->getName())) {

core/modules/system/src/Form/ModulesListForm.php

@@ -281,10 +281,14 @@ class ModulesListForm extends FormBase {
     $reasons = [];
 
     // Check the core compatibility.
-    if ($module->info['core'] != \Drupal::CORE_COMPATIBILITY) {
+    if ($module->info['core_incompatible']) {
       $compatible = FALSE;
       $reasons[] = $this->t('This version is not compatible with Drupal @core_version and should be replaced.', [
-        '@core_version' => \Drupal::CORE_COMPATIBILITY,
+        '@core_version' => \Drupal::VERSION,
+      ]);
+      $row['#requires']['core'] = $this->t('Drupal Core (@core_requirement) (<span class="admin-missing">incompatible with</span> version @core_version)', [
+        '@core_requirement' => isset($module->info['core_version_requirement']) ? $module->info['core_version_requirement'] : $module->info['core'],
+        '@core_version' => \Drupal::VERSION,
       ]);
     }
 
@@ -328,7 +332,7 @@ class ModulesListForm extends FormBase {
         }
         // Disable the checkbox if the dependency is incompatible with this
         // version of Drupal core.
-        elseif ($modules[$dependency]->info['core'] != \Drupal::CORE_COMPATIBILITY) {
+        elseif ($modules[$dependency]->info['core_incompatible']) {
           $row['#requires'][$dependency] = $this->t('@module (<span class="admin-missing">incompatible with</span> this version of Drupal core)', [
             '@module' => $name,
           ]);

core/modules/system/system.admin.inc

@@ -292,8 +292,8 @@ function template_preprocess_system_themes_page(&$variables) {
 
       // Make sure to provide feedback on compatibility.
       $current_theme['incompatible'] = '';
-      if (!empty($theme->incompatible_core)) {
-        $current_theme['incompatible'] = t("This theme is not compatible with Drupal @core_version. Check that the .info.yml file contains the correct 'core' value.", ['@core_version' => \Drupal::CORE_COMPATIBILITY]);
+      if (!empty($theme->info['core_incompatible'])) {
+        $current_theme['incompatible'] = t("This theme is not compatible with Drupal @core_version. Check that the .info.yml file contains a compatible 'core' or 'core_version_requirement' value.", ['@core_version' => \Drupal::VERSION]);
       }
       elseif (!empty($theme->incompatible_region)) {
         $current_theme['incompatible'] = t("This theme is missing a 'content' region.");

core/modules/system/tests/fixtures/update/drupal-8.update-test-semver-update-n-enabled.php

@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Database to mimic the installation of the update_test_semver_update_n module.
+ */
+
+use Drupal\Core\Database\Database;
+
+$connection = Database::getConnection();
+
+// Set the schema version.
+$connection->merge('key_value')
+  ->condition('collection', 'system.schema')
+  ->condition('name', 'update_test_semver_update_n')
+  ->fields([
+    'collection' => 'system.schema',
+    'name' => 'update_test_semver_update_n',
+    'value' => 'i:8000;',
+  ])
+  ->execute();
+
+// Update core.extension.
+$extensions = $connection->select('config')
+  ->fields('config', ['data'])
+  ->condition('collection', '')
+  ->condition('name', 'core.extension')
+  ->execute()
+  ->fetchField();
+$extensions = unserialize($extensions);
+$extensions['module']['update_test_semver_update_n'] = 8000;
+$connection->update('config')
+  ->fields([
+    'data' => serialize($extensions),
+  ])
+  ->condition('collection', '')
+  ->condition('name', 'core.extension')
+  ->execute();

core/modules/system/tests/modules/system_core_incompatible_semver_test/system_core_incompatible_semver_test.info.yml

@@ -0,0 +1,6 @@
+name: 'System core incompatible semver test'
+type: module
+description: 'Support module for testing core incompatible semver.'
+package: Testing
+version: 1.0.0
+core_version_requirement: ^7

core/modules/system/tests/modules/system_core_semver_test/system_core_semver_test.info.yml

@@ -0,0 +1,6 @@
+name: 'System core ^8 version test'
+type: module
+description: 'Support module for testing core using semver.'
+package: Testing
+version: 1.0.0
+core_version_requirement: ^8

core/modules/system/tests/modules/system_incompatible_core_version_test_1x/system_incompatible_core_version_test_1x.info.yml

@@ -0,0 +1,6 @@
+name: 'System incompatible core 1.x version test'
+type: module
+description: 'Support module for testing system core incompatibility.'
+package: Testing
+version: 1.0.0
+core: 1.x

core/modules/system/tests/modules/system_test/system_test.module

@@ -71,6 +71,7 @@ function system_test_system_info_alter(&$info, Extension $file, $type) {
     'system_incompatible_core_version_dependencies_test',
     'system_incompatible_module_version_test',
     'system_incompatible_core_version_test',
+    'system_incompatible_core_version_test_1x',
   ])) {
     $info['hidden'] = FALSE;
   }

core/modules/system/tests/modules/update_test_semver_update_n/update_test_semver_update_n.info.yml

@@ -0,0 +1,6 @@
+name: 'Update test hook_update_n semver'
+type: module
+description: 'Support module for update testing with core semver value.'
+package: Testing
+version: VERSION
+core_version_requirement: ^8

core/modules/system/tests/modules/update_test_semver_update_n/update_test_semver_update_n.install

@@ -0,0 +1,13 @@
+<?php
+
+/**
+ * @file
+ * Update hooks for the update_test_semver_update_n module.
+ */
+
+/**
+ * Update 8001.
+ */
+function update_test_semver_update_n_update_8001() {
+  \Drupal::state()->set('update_test_semver_update_n_update_8001', 'Yes, I was run. Thanks for testing!');
+}

core/modules/system/tests/src/Functional/Form/ModulesListFormWebTest.php

@@ -70,7 +70,7 @@ BROKEN;
 
     // Confirm that the error message is shown.
     $this->assertSession()
-      ->pageTextContains('Modules could not be listed due to an error: Missing required keys (core) in ' . $path . '/broken.info.yml');
+      ->pageTextContains("The 'core' or the 'core_version_requirement' key must be present in " . $path . '/broken.info.yml');
 
     // Check that the module filter text box is available.
     $this->assertTrue($this->xpath('//input[@name="text"]'));

core/modules/system/tests/src/Functional/Module/DependencyTest.php

@@ -102,6 +102,29 @@ class DependencyTest extends ModuleTestBase {
     $this->assert(count($checkbox) == 1, 'Checkbox for the module is disabled.');
   }
 
+  /**
+   * Tests enabling modules with different core version specifications.
+   */
+  public function testCoreCompatibility() {
+    $assert_session = $this->assertSession();
+
+    // Test incompatible 'core_version_requirement'.
+    $this->drupalGet('admin/modules');
+    $assert_session->fieldDisabled('modules[system_incompatible_core_version_test_1x][enable]');
+    $assert_session->fieldDisabled('modules[system_core_incompatible_semver_test][enable]');
+
+    // Test compatible 'core_version_requirement' and compatible 'core'.
+    $this->drupalGet('admin/modules');
+    $assert_session->fieldEnabled('modules[common_test][enable]');
+    $assert_session->fieldEnabled('modules[system_core_semver_test][enable]');
+
+    // Ensure the modules can actually be installed.
+    $edit['modules[common_test][enable]'] = 'common_test';
+    $edit['modules[system_core_semver_test][enable]'] = 'system_core_semver_test';
+    $this->drupalPostForm('admin/modules', $edit, t('Install'));
+    $this->assertModules(['common_test', 'system_core_semver_test'], TRUE);
+  }
+
   /**
    * Tests enabling a module that depends on a module which fails hook_requirements().
    */

core/modules/system/tests/src/Functional/System/ThemeTest.php

@@ -366,8 +366,11 @@ class ThemeTest extends BrowserTestBase {
     $this->assertText(t('This theme requires the base theme @base_theme to operate correctly.', ['@base_theme' => 'not_real_test_basetheme']));
     $this->assertText(t('This theme requires the base theme @base_theme to operate correctly.', ['@base_theme' => 'test_invalid_basetheme']));
     $this->assertText(t('This theme requires the theme engine @theme_engine to operate correctly.', ['@theme_engine' => 'not_real_engine']));
-    // Check for the error text of a theme with the wrong core version.
-    $this->assertText("This theme is not compatible with Drupal 8.x. Check that the .info.yml file contains the correct 'core' value.");
+    // Check for the error text of a theme with the wrong core version
+    // using 7.x and ^7.
+    $incompatible_core_message = 'This theme is not compatible with Drupal ' . \Drupal::VERSION . ". Check that the .info.yml file contains a compatible 'core' or 'core_version_requirement' value.";
+    $this->assertThemeIncompatibleText('Theme test with invalid core version', $incompatible_core_message);
+    $this->assertThemeIncompatibleText('Theme test with invalid semver core version', $incompatible_core_message);
     // Check for the error text of a theme without a content region.
     $this->assertText("This theme is missing a 'content' region.");
   }
@@ -436,24 +439,28 @@ class ThemeTest extends BrowserTestBase {
    * Tests installing a theme and setting it as default.
    */
   public function testInstallAndSetAsDefault() {
-    $this->drupalGet('admin/appearance');
-    // Bartik is uninstalled in the test profile and has the third "Install and
-    // set as default" link.
-    $this->clickLink(t('Install and set as default'), 2);
-    // Test the confirmation message.
-    $this->assertText('Bartik is now the default theme.');
-    // Make sure Bartik is now set as the default theme in config.
-    $this->assertEqual($this->config('system.theme')->get('default'), 'bartik');
+    $themes = [
+      'bartik' => 'Bartik',
+      'test_core_semver' => 'Theme test with semver core version',
+    ];
+    foreach ($themes as $theme_machine_name => $theme_name) {
+      $this->drupalGet('admin/appearance');
+      $this->getSession()->getPage()->findLink("Install $theme_name as default theme")->click();
+      // Test the confirmation message.
+      $this->assertText("$theme_name is now the default theme.");
+      // Make sure the theme is now set as the default theme in config.
+      $this->assertEqual($this->config('system.theme')->get('default'), $theme_machine_name);
 
-    // This checks for a regression. See https://www.drupal.org/node/2498691.
-    $this->assertNoText('The bartik theme was not found.');
+      // This checks for a regression. See https://www.drupal.org/node/2498691.
+      $this->assertNoText("The $theme_machine_name theme was not found.");
 
-    $themes = \Drupal::service('theme_handler')->rebuildThemeData();
-    $version = $themes['bartik']->info['version'];
+      $themes = \Drupal::service('theme_handler')->rebuildThemeData();
+      $version = $themes[$theme_machine_name]->info['version'];
 
-    // Confirm Bartik is indicated as the default theme.
-    $out = $this->getSession()->getPage()->getContent();
-    $this->assertTrue((bool) preg_match('/Bartik ' . preg_quote($version) . '\s{2,}\(default theme\)/', $out));
+      // Confirm the theme is indicated as the default theme.
+      $out = $this->getSession()->getPage()->getContent();
+      $this->assertTrue((bool) preg_match("/$theme_name " . preg_quote($version) . '\s{2,}\(default theme\)/', $out));
+    }
   }
 
   /**
@@ -469,4 +476,16 @@ class ThemeTest extends BrowserTestBase {
     $this->assertText('The configuration options have been saved.');
   }
 
+  /**
+   * Asserts that expected incompatibility text is displayed for a theme.
+   *
+   * @param string $theme_name
+   *   Theme name to select element on page. This can be a partial name.
+   * @param string $expected_text
+   *   The expected incompatibility text.
+   */
+  private function assertThemeIncompatibleText($theme_name, $expected_text) {
+    $this->assertSession()->elementExists('css', ".theme-info:contains(\"$theme_name\") .incompatible:contains(\"$expected_text\")");
+  }
+
 }

core/modules/system/tests/themes/test_core_semver/test_core_semver.info.yml

@@ -0,0 +1,5 @@
+name: 'Theme test with semver core version'
+type: theme
+description: 'Test theme which has semver core version.'
+version: VERSION
+core_version_requirement: ^8 || ^9

core/modules/system/tests/themes/test_invalid_core_semver/test_invalid_core_semver.info.yml

@@ -0,0 +1,5 @@
+name: 'Theme test with invalid semver core version'
+type: theme
+description: 'Test theme which has an invalid semver core version.'
+version: VERSION
+core_version_requirement: ^7

core/modules/update/update.module

@@ -696,7 +696,7 @@ function update_verify_update_archive($project, $archive_file, $directory) {
     $info = \Drupal::service('info_parser')->parse($file->uri);
 
     // If the module or theme is incompatible with Drupal core, set an error.
-    if (empty($info['core']) || $info['core'] != \Drupal::CORE_COMPATIBILITY) {
+    if ($info['core_incompatible']) {
       $incompatible[] = !empty($info['name']) ? $info['name'] : t('Unknown');
     }
     else {
@@ -716,7 +716,7 @@ function update_verify_update_archive($project, $archive_file, $directory) {
       '%archive_file contains a version of %names that is not compatible with Drupal @version.',
       '%archive_file contains versions of modules or themes that are not compatible with Drupal @version: %names',
       [
-        '@version' => \Drupal::CORE_COMPATIBILITY,
+        '@version' => \Drupal::VERSION,
         '%archive_file' => $file_system->basename($archive_file),
         '%names' => implode(', ', $incompatible),
       ]

core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBaseTest.php

@@ -26,6 +26,7 @@ class UpdatePathTestBaseTest extends UpdatePathTestBase {
     $this->databaseDumpFiles = [
       __DIR__ . '/../../../../modules/system/tests/fixtures/update/drupal-8.bare.standard.php.gz',
       __DIR__ . '/../../../../modules/system/tests/fixtures/update/drupal-8.update-test-schema-enabled.php',
+      __DIR__ . '/../../../../modules/system/tests/fixtures/update/drupal-8.update-test-semver-update-n-enabled.php',
     ];
   }
 
@@ -99,8 +100,11 @@ class UpdatePathTestBaseTest extends UpdatePathTestBase {
 
     // Ensure schema has changed.
     $this->assertEqual(drupal_get_installed_schema_version('update_test_schema', TRUE), 8001);
+    $this->assertEqual(drupal_get_installed_schema_version('update_test_semver_update_n', TRUE), 8001);
     // Ensure the index was added for column a.
     $this->assertTrue($connection->schema()->indexExists('update_test_schema_table', 'test'), 'Version 8001 of the update_test_schema module is installed.');
+    // Ensure update_test_semver_update_n_update_8001 was run.
+    $this->assertEquals(\Drupal::state()->get('update_test_semver_update_n_update_8001'), 'Yes, I was run. Thanks for testing!');
   }
 
   /**

core/tests/Drupal/KernelTests/Core/Extension/ModuleInstallerTest.php

@@ -3,6 +3,7 @@
 namespace Drupal\KernelTests\Core\Extension;
 
 use Drupal\Core\Database\Database;
+use Drupal\Core\Extension\MissingDependencyException;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\Routing\Exception\RouteNotFoundException;
 
@@ -94,4 +95,60 @@ class ModuleInstallerTest extends KernelTestBase {
     $this->assertTrue($module_installer->install(['module_test']));
   }
 
+  /**
+   * Tests install with a module with an invalid core version constraint.
+   *
+   * @dataProvider providerTestInvalidCoreInstall
+   * @covers ::install
+   */
+  public function testInvalidCoreInstall($module_name, $install_dependencies) {
+    $this->expectException(MissingDependencyException::class);
+    $this->expectExceptionMessage("Unable to install modules: module '$module_name' is incompatible with this version of Drupal core.");
+    $this->container->get('module_installer')->install([$module_name], $install_dependencies);
+  }
+
+  /**
+   * Dataprovider for testInvalidCoreInstall().
+   */
+  public function providerTestInvalidCoreInstall() {
+    return [
+      'no dependencies system_incompatible_core_version_test_1x' => [
+        'system_incompatible_core_version_test_1x',
+        FALSE,
+      ],
+      'install_dependencies system_incompatible_core_version_test_1x' => [
+        'system_incompatible_core_version_test_1x',
+        TRUE,
+      ],
+      'no dependencies system_core_incompatible_semver_test' => [
+        'system_core_incompatible_semver_test',
+        FALSE,
+      ],
+      'install_dependencies system_core_incompatible_semver_test' => [
+        'system_core_incompatible_semver_test',
+        TRUE,
+      ],
+    ];
+  }
+
+  /**
+   * Tests install with a dependency with an invalid core version constraint.
+   *
+   * @covers ::install
+   */
+  public function testDependencyInvalidCoreInstall() {
+    $this->expectException(MissingDependencyException::class);
+    $this->expectExceptionMessage("Unable to install modules: module 'system_incompatible_core_version_dependencies_test'. Its dependency module 'system_incompatible_core_version_test' is incompatible with this version of Drupal core.");
+    $this->container->get('module_installer')->install(['system_incompatible_core_version_dependencies_test']);
+  }
+
+  /**
+   * Tests no dependencies install with a dependency with invalid core.
+   *
+   * @covers ::install
+   */
+  public function testDependencyInvalidCoreInstallNoDependencies() {
+    $this->assertTrue($this->container->get('module_installer')->install(['system_incompatible_core_version_dependencies_test'], FALSE));
+  }
+
 }

core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php

@@ -3,6 +3,7 @@
 namespace Drupal\Tests\Core\Extension;
 
 use Drupal\Core\Extension\InfoParser;
+use Drupal\Core\Extension\InfoParserException;
 use Drupal\Tests\UnitTestCase;
 use org\bovigo\vfs\vfsStream;
 
@@ -96,10 +97,212 @@ MISSINGKEYS;
       ],
     ]);
     $filename = vfsStream::url('modules/fixtures/missing_keys.info.txt');
-    $this->setExpectedException('\Drupal\Core\Extension\InfoParserException', 'Missing required keys (type, core, name) in vfs://modules/fixtures/missing_keys.info.txt');
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage('Missing required keys (type, name) in vfs://modules/fixtures/missing_keys.info.txt');
     $this->infoParser->parse($filename);
   }
 
+  /**
+   * Tests that missing 'core' and 'core_version_requirement' keys are detected.
+   *
+   * @covers ::parse
+   */
+  public function testMissingCoreCoreVersionRequirement() {
+    $missing_core_and_core_version_requirement = <<<MISSING_CORE_AND_CORE_VERSION_REQUIREMENT
+# info.yml for testing core and core_version_requirement.
+package: Core
+version: VERSION
+type: module
+name: Skynet
+dependencies:
+  - self_awareness
+MISSING_CORE_AND_CORE_VERSION_REQUIREMENT;
+
+    vfsStream::setup('modules');
+    vfsStream::create([
+      'fixtures' => [
+        'missing_core_and_core_version_requirement.info.txt' => $missing_core_and_core_version_requirement,
+        'missing_core_and_core_version_requirement-duplicate.info.txt' => $missing_core_and_core_version_requirement,
+      ],
+    ]);
+    $exception_message = "The 'core' or the 'core_version_requirement' key must be present in vfs://modules/fixtures/missing_core_and_core_version_requirement";
+    // Set the expected exception for the 2nd call to parse().
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("$exception_message-duplicate.info.txt");
+
+    try {
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/missing_core_and_core_version_requirement.info.txt'));
+    }
+    catch (InfoParserException $exception) {
+      $this->assertSame("$exception_message.info.txt", $exception->getMessage());
+
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/missing_core_and_core_version_requirement-duplicate.info.txt'));
+    }
+  }
+
+  /**
+   * Tests that 'core_version_requirement: ^8.8' is valid with no 'core' key.
+   *
+   * @covers ::parse
+   */
+  public function testCoreVersionRequirement88() {
+    $core_version_requirement = <<<BOTH_CORE_VERSION_REQUIREMENT
+# info.yml for testing core and core_version_requirement keys.
+package: Core
+core_version_requirement: ^8.8
+version: VERSION
+type: module
+name: Module for That
+dependencies:
+  - field
+BOTH_CORE_VERSION_REQUIREMENT;
+
+    vfsStream::setup('modules');
+    foreach (['1', '2'] as $file_delta) {
+      $filename = "core_version_requirement-$file_delta.info.txt";
+      vfsStream::create([
+        'fixtures' => [
+          $filename => $core_version_requirement,
+        ],
+      ]);
+      $info_values = $this->infoParser->parse(vfsStream::url("modules/fixtures/$filename"));
+      $this->assertSame($info_values['core_version_requirement'], '^8.8', "Expected core_version_requirement for file: $filename");
+    }
+  }
+
+  /**
+   * Tests that 'core_version_requirement: ^8.8' is invalid with a 'core' key.
+   *
+   * @covers ::parse
+   */
+  public function testCoreCoreVersionRequirement88() {
+    $core_and_core_version_requirement_88 = <<<BOTH_CORE_CORE_VERSION_REQUIREMENT_88
+# info.yml for testing core and core_version_requirement keys.
+package: Core
+core: 8.x
+core_version_requirement: ^8.8
+version: VERSION
+type: module
+name: Form auto submitter
+dependencies:
+  - field
+BOTH_CORE_CORE_VERSION_REQUIREMENT_88;
+
+    vfsStream::setup('modules');
+    vfsStream::create([
+      'fixtures' => [
+        'core_and_core_version_requirement_88.info.txt' => $core_and_core_version_requirement_88,
+        'core_and_core_version_requirement_88-duplicate.info.txt' => $core_and_core_version_requirement_88,
+      ],
+    ]);
+    $exception_message = "The 'core_version_requirement' constraint (^8.8) requires the 'core' key not be set in vfs://modules/fixtures/core_and_core_version_requirement_88";
+    // Set the expected exception for the 2nd call to parse().
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("$exception_message-duplicate.info.txt");
+    try {
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/core_and_core_version_requirement_88.info.txt'));
+    }
+    catch (InfoParserException $exception) {
+      $this->assertSame("$exception_message.info.txt", $exception->getMessage());
+
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/core_and_core_version_requirement_88-duplicate.info.txt'));
+    }
+  }
+
+  /**
+   * Tests a invalid 'core' key.
+   *
+   * @covers ::parse
+   */
+  public function testInvalidCore() {
+    $invalid_core = <<<INVALID_CORE
+# info.yml for testing invalid core key.
+package: Core
+core: ^8
+version: VERSION
+type: module
+name: Llama or Alpaca
+description: Tells whether an image is of a Llama or Alpaca
+dependencies:
+  - llama_detector
+  - alpaca_detector
+INVALID_CORE;
+
+    vfsStream::setup('modules');
+    vfsStream::create([
+      'fixtures' => [
+        'invalid_core.info.txt' => $invalid_core,
+        'invalid_core-duplicate.info.txt' => $invalid_core,
+      ],
+    ]);
+    $exception_message = "Invalid 'core' value \"^8\" in vfs://modules/fixtures/invalid_core";
+    // Set the expected exception for the 2nd call to parse().
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("$exception_message-duplicate.info.txt");
+
+    try {
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/invalid_core.info.txt'));
+    }
+    catch (InfoParserException $exception) {
+      $this->assertSame("$exception_message.info.txt", $exception->getMessage());
+
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/invalid_core-duplicate.info.txt'));
+    }
+  }
+
+  /**
+   * Tests a invalid 'core_version_requirement'.
+   *
+   * @covers ::parse
+   *
+   * @dataProvider providerCoreVersionRequirementInvalid
+   */
+  public function testCoreVersionRequirementInvalid($test_case, $constraint) {
+    $invalid_core_version_requirement = <<<INVALID_CORE_VERSION_REQUIREMENT
+# info.yml for core_version_requirement validation.
+name: Gracie Evaluator
+description: 'Determines if Gracie is a "Good Dog". The answer is always "Yes".'
+package: Core
+type: module
+version: VERSION
+core_version_requirement: '$constraint'
+dependencies:
+  - goodness_api
+INVALID_CORE_VERSION_REQUIREMENT;
+
+    vfsStream::setup('modules');
+    vfsStream::create([
+      'fixtures' => [
+        "invalid_core_version_requirement-$test_case.info.txt" => $invalid_core_version_requirement,
+        "invalid_core_version_requirement-$test_case-duplicate.info.txt" => $invalid_core_version_requirement,
+      ],
+    ]);
+    $exception_message = "The 'core_version_requirement' can not be used to specify compatibility for a specific version before 8.7.7 in vfs://modules/fixtures/invalid_core_version_requirement-$test_case";
+    // Set the expected exception for the 2nd call to parse().
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("$exception_message-duplicate.info.txt");
+    try {
+      $this->infoParser->parse(vfsStream::url("modules/fixtures/invalid_core_version_requirement-$test_case.info.txt"));
+    }
+    catch (InfoParserException $exception) {
+      $this->assertSame("$exception_message.info.txt", $exception->getMessage());
+
+      $this->infoParser->parse(vfsStream::url("modules/fixtures/invalid_core_version_requirement-$test_case-duplicate.info.txt"));
+    }
+  }
+
+  /**
+   * Dataprovider for testCoreVersionRequirementInvalid().
+   */
+  public function providerCoreVersionRequirementInvalid() {
+    return [
+      '8.0.0-alpha2' => ['alpha2', '8.0.0-alpha2'],
+      '8.6.0-rc1' => ['rc1', '8.6.0-rc1'],
+      '^8.7' => ['8_7', '^8.7'],
+      '>8.6.3' => ['gt8_6_3', '>8.6.3'],
+    ];
+  }
+
   /**
    * Tests that missing required key is detected.
    *
@@ -121,11 +324,20 @@ MISSINGKEY;
     vfsStream::create([
       'fixtures' => [
         'missing_key.info.txt' => $missing_key,
+        'missing_key-duplicate.info.txt' => $missing_key,
       ],
     ]);
-    $filename = vfsStream::url('modules/fixtures/missing_key.info.txt');
-    $this->setExpectedException('\Drupal\Core\Extension\InfoParserException', 'Missing required keys (type) in vfs://modules/fixtures/missing_key.info.txt');
-    $this->infoParser->parse($filename);
+    try {
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/missing_key.info.txt'));
+    }
+    catch (InfoParserException $exception) {
+      $this->assertSame('Missing required keys (type) in vfs://modules/fixtures/missing_key.info.txt', $exception->getMessage());
+
+      $this->expectException('\Drupal\Core\Extension\InfoParserException');
+      $this->expectExceptionMessage('Missing required keys (type) in vfs://modules/fixtures/missing_key-duplicate.info.txt');
+      $this->infoParser->parse(vfsStream::url('modules/fixtures/missing_key-duplicate.info.txt'));
+    }
+
   }
 
   /**
@@ -145,15 +357,106 @@ double_colon: dummyClassName::method
 COMMONTEST;
 
     vfsStream::setup('modules');
+
+    foreach (['1', '2'] as $file_delta) {
+      $filename = "common_test-$file_delta.info.txt";
+      vfsStream::create([
+        'fixtures' => [
+          $filename => $common,
+        ],
+      ]);
+      $info_values = $this->infoParser->parse(vfsStream::url("modules/fixtures/$filename"));
+      $this->assertEquals($info_values['simple_string'], 'A simple string', 'Simple string value was parsed correctly.');
+      $this->assertEquals($info_values['version'], \Drupal::VERSION, 'Constant value was parsed correctly.');
+      $this->assertEquals($info_values['double_colon'], 'dummyClassName::method', 'Value containing double-colon was parsed correctly.');
+      $this->assertSame('8.x', $info_values['core']);
+      $this->assertFalse(isset($info_values['core_version_requirement']));
+      $this->assertFalse($info_values['core_incompatible']);
+    }
+  }
+
+  /**
+   * @covers ::parse
+   *
+   * @dataProvider providerCoreIncompatibility
+   */
+  public function testCoreIncompatibility($test_case, $constraint, $expected) {
+    $core_incompatibility = <<<CORE_INCOMPATIBILITY
+core_version_requirement: $constraint
+name: common_test
+type: module
+description: 'testing info file parsing'
+simple_string: 'A simple string'
+version: "VERSION"
+double_colon: dummyClassName::method
+CORE_INCOMPATIBILITY;
+
+    vfsStream::setup('modules');
+    foreach (['1', '2'] as $file_delta) {
+      $filename = "core_incompatible-$test_case-$file_delta.info.txt";
+      vfsStream::create([
+        'fixtures' => [
+          $filename => $core_incompatibility,
+        ],
+      ]);
+      $info_values = $this->infoParser->parse(vfsStream::url("modules/fixtures/$filename"));
+      $this->assertSame($expected, $info_values['core_incompatible'], "core_incompatible correct in file: $filename");
+    }
+  }
+
+  /**
+   * Dataprovider for testCoreIncompatibility().
+   */
+  public function providerCoreIncompatibility() {
+    list($major, $minor) = explode('.', \Drupal::VERSION);
+
+    $next_minor = $minor + 1;
+    $next_major = $major + 1;
+    return [
+      'next_minor' => [
+        'next_minor',
+        "^$major.$next_minor",
+        TRUE,
+      ],
+      'current_major_next_major' => [
+        'current_major_next_major',
+        "^$major || ^$next_major",
+        FALSE,
+      ],
+      'previous_major_next_major' => [
+        'previous_major_next_major',
+        "^1 || ^$next_major",
+        TRUE,
+      ],
+      'invalid' => [
+        'invalid',
+        'this-string-is-invalid',
+        TRUE,
+      ],
+    ];
+  }
+
+  /**
+   * Test a profile info file with the 'core_version_requirement' key.
+   */
+  public function testInvalidProfile() {
+    $profile = <<<PROFILE_TEST
+core: 8.x
+core_version_requirement: ^8
+name: The Perfect Profile
+type: profile
+description: 'This profile makes Drupal perfect. You should have no complaints.'
+PROFILE_TEST;
+
+    vfsStream::setup('profiles');
     vfsStream::create([
       'fixtures' => [
-        'common_test.info.txt' => $common,
+        'invalid_profile.info.txt' => $profile,
       ],
     ]);
-    $info_values = $this->infoParser->parse(vfsStream::url('modules/fixtures/common_test.info.txt'));
-    $this->assertEquals($info_values['simple_string'], 'A simple string', 'Simple string value was parsed correctly.');
-    $this->assertEquals($info_values['version'], \Drupal::VERSION, 'Constant value was parsed correctly.');
-    $this->assertEquals($info_values['double_colon'], 'dummyClassName::method', 'Value containing double-colon was parsed correctly.');
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("The 'core_version_requirement' key is not supported in profiles in vfs://profiles/fixtures/invalid_profile.info.txt");
+    $this->infoParser->parse(vfsStream::url('profiles/fixtures/invalid_profile.info.txt'));
   }
 
 }

core/tests/Drupal/Tests/WebAssert.php

@@ -491,6 +491,35 @@ class WebAssert extends MinkWebAssert {
     return $node;
   }
 
+  /**
+   * Checks that a given form field element is enabled.
+   *
+   * @param string $field
+   *   One of id|name|label|value for the field.
+   * @param \Behat\Mink\Element\TraversableElement $container
+   *   (optional) The document to check against. Defaults to the current page.
+   *
+   * @return \Behat\Mink\Element\NodeElement
+   *   The matching element.
+   *
+   * @throws \Behat\Mink\Exception\ElementNotFoundException
+   * @throws \Behat\Mink\Exception\ExpectationException
+   */
+  public function fieldEnabled($field, TraversableElement $container = NULL) {
+    $container = $container ?: $this->session->getPage();
+    $node = $container->findField($field);
+
+    if ($node === NULL) {
+      throw new ElementNotFoundException($this->session->getDriver(), 'field', 'id|name|label|value', $field);
+    }
+
+    if ($node->hasAttribute('disabled')) {
+      throw new ExpectationException("Field $field is not enabled", $this->session->getDriver());
+    }
+
+    return $node;
+  }
+
   /**
    * Checks that specific hidden field exists.
    *