diff --git a/core/lib/Drupal/Component/Version/DrupalSemver.php b/core/lib/Drupal/Component/Version/DrupalSemver.php
index 74cdd7be70..bfce92e17a 100644
--- a/core/lib/Drupal/Component/Version/DrupalSemver.php
+++ b/core/lib/Drupal/Component/Version/DrupalSemver.php
@@ -21,7 +21,7 @@ class DrupalSemver {
    *   The constraints.
    *
    * @return bool
-   *   TRUE if the version satisfies the constraints.
+   *   TRUE if the version satisfies the constraints, otherwise FALSE.
    *
    * @see \Composer\Semver\Semver::satisfies()
    */
diff --git a/core/lib/Drupal/Core/Extension/InfoParserDynamic.php b/core/lib/Drupal/Core/Extension/InfoParserDynamic.php
index b787bd4c02..806966f9c5 100644
--- a/core/lib/Drupal/Core/Extension/InfoParserDynamic.php
+++ b/core/lib/Drupal/Core/Extension/InfoParserDynamic.php
@@ -35,14 +35,14 @@ public function parse($filename) {
         throw new InfoParserException("The 'core' or the 'core_dependency' key must be present in " . $filename);
       }
       if (isset($parsed_info['core']) && !preg_match("/^\d\.x$/", $parsed_info['core'])) {
-        throw new InfoParserException("The {$parsed_info['core']} is not valid value for  'core' in " . $filename);
+        throw new InfoParserException("Invalid 'core' value \"{$parsed_info['core']}\" in " . $filename);
       }
       if (isset($parsed_info['core_dependency'])) {
         $supports_pre_core_dependency_version = $this->isConstraintSatisfiedByPreCoreDependencyCoreVersion($parsed_info['core_dependency']);
         // If the 'core_dependency' constraint does not satisfy any Drupal 8
-        // versions before 8.7.7 then the 'core' cannot be set or it will
-        // effectively support all version of Drupal 8 because 'core_dependency'
-        // will be ignored.
+        // versions before 8.7.7 then 'core' cannot be set or it will
+        // effectively support all versions of Drupal 8 because
+        // 'core_dependency' will be ignored in previous versions.
         if (!$supports_pre_core_dependency_version && isset($parsed_info['core'])) {
           throw new InfoParserException("The 'core_dependency' constraint ({$parsed_info['core_dependency']}) requires the 'core' not be set in " . $filename);
         }
diff --git a/core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php b/core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php
index c9cb79c6ad..19746f1da6 100644
--- a/core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php
+++ b/core/tests/Drupal/Tests/Core/Extension/InfoParserUnitTest.php
@@ -108,25 +108,25 @@ public function testInfoParserMissingKeys() {
    * @covers ::parse
    */
   public function testMissingCoreCoreDependency() {
-    $missing_keys = <<<MISSINGKEYS
-# info.yml for testing missing name, description, and type keys.
+    $missing_core_and_core_dependency = <<<MISSING_CORE_AND_CORE_DEPENDENCY
+# info.yml for testing core and core_dependency.
 package: Core
 version: VERSION
 type: module
-name: Really Cool Module
+name: Skynet
 dependencies:
-  - field
-MISSINGKEYS;
+  - self_awareness
+MISSING_CORE_AND_CORE_DEPENDENCY;
 
     vfsStream::setup('modules');
     vfsStream::create([
       'fixtures' => [
-        'missing_keys.info.txt' => $missing_keys,
+        'missing_core_and_core_dependency.info.txt' => $missing_core_and_core_dependency,
       ],
     ]);
-    $filename = vfsStream::url('modules/fixtures/missing_keys.info.txt');
+    $filename = vfsStream::url('modules/fixtures/missing_core_and_core_dependency.info.txt');
     $this->expectException('\Drupal\Core\Extension\InfoParserException');
-    $this->expectExceptionMessage("The 'core' or the 'core_dependency' key must be present in vfs://modules/fixtures/missing_keys.info.txt");
+    $this->expectExceptionMessage("The 'core' or the 'core_dependency' key must be present in vfs://modules/fixtures/missing_core_and_core_dependency.info.txt");
     $this->infoParser->parse($filename);
   }
 
@@ -136,24 +136,24 @@ public function testMissingCoreCoreDependency() {
    * @covers ::parse
    */
   public function testCoreDependency88() {
-    $core_and_core_dependency = <<<BOTHCORECOREDEPENDENCY
+    $core_dependency = <<<BOTH_CORE_DEPENDENCY
 # info.yml for testing core and core_dependency keys.
 package: Core
 core_dependency: ^8.8
 version: VERSION
 type: module
-name: Really Cool Module
+name: Module for That
 dependencies:
   - field
-BOTHCORECOREDEPENDENCY;
+BOTH_CORE_DEPENDENCY;
 
     vfsStream::setup('modules');
     vfsStream::create([
       'fixtures' => [
-        'core_and_core_dependency.info.txt' => $core_and_core_dependency,
+        'core_dependency.info.txt' => $core_dependency,
       ],
     ]);
-    $filename = vfsStream::url('modules/fixtures/core_and_core_dependency.info.txt');
+    $filename = vfsStream::url('modules/fixtures/core_dependency.info.txt');
     $info_values = $this->infoParser->parse($filename);
     $this->assertSame($info_values['core_dependency'], '^8.8');
   }
@@ -164,17 +164,17 @@ public function testCoreDependency88() {
    * @covers ::parse
    */
   public function testCoreCoreDependency88() {
-    $core_and_core_dependency_88 = <<<BOTHCORECOREDEPENDENCY88
+    $core_and_core_dependency_88 = <<<BOTH_CORE_CORE_DEPENDENCY_88
 # info.yml for testing core and core_dependency keys.
 package: Core
 core: 8.x
 core_dependency: ^8.8
 version: VERSION
 type: module
-name: Really Cool Module
+name: Form auto submitter
 dependencies:
   - field
-BOTHCORECOREDEPENDENCY88;
+BOTH_CORE_CORE_DEPENDENCY_88;
 
     vfsStream::setup('modules');
     vfsStream::create([
@@ -189,31 +189,33 @@ public function testCoreCoreDependency88() {
   }
 
   /**
-   * Tests that missing required key is detected.
+   * Tests that 'core_dependency: ^8.8' is invalid with a 'core' key.
    *
    * @covers ::parse
    */
-  public function testInfoParserMissingKey() {
-    $missing_key = <<<MISSINGKEY
-# info.yml for testing missing type key.
-name: File
-description: 'Defines a file field type.'
+  public function testInvalidCore() {
+    $invalid_core = <<<INVALID_CORE
+# info.yml for testing invalid core key.
 package: Core
+core: ^8
 version: VERSION
-core: 8.x
+type: module
+name: Llama or Alpaca
+description: Tells whether an image is of a Llama or Alpaca
 dependencies:
-  - field
-MISSINGKEY;
+  - llama_detector
+  - alpaca_detector
+INVALID_CORE;
 
     vfsStream::setup('modules');
     vfsStream::create([
       'fixtures' => [
-        'missing_key.info.txt' => $missing_key,
+        'invalid_core.info.txt' => $invalid_core,
       ],
     ]);
-    $filename = vfsStream::url('modules/fixtures/missing_key.info.txt');
+    $filename = vfsStream::url('modules/fixtures/invalid_core.info.txt');
     $this->expectException('\Drupal\Core\Extension\InfoParserException');
-    $this->expectExceptionMessage('Missing required keys (type) in vfs://modules/fixtures/missing_key.info.txt');
+    $this->expectExceptionMessage("Invalid 'core' value \"^8\" in vfs://modules/fixtures/invalid_core.info.txt");
     $this->infoParser->parse($filename);
   }
 
@@ -223,27 +225,56 @@ public function testInfoParserMissingKey() {
    * @covers ::parse
    */
   public function testCoreDependencyInvalid() {
-    $core_dependency_invalid = <<<COREDEPENDENCYINVALID
+    $invalid_core_dependency = <<<INVALID_CORE_DEPENDENCY
 # info.yml for core_dependency validation.
-name: Big Forms 
-description: 'Alters all forms to be a little bit bigger.'
+name: Gracie Evaluator
+description: 'Determines if Gracie is a "Good Dog". The answer is always "Yes".'
 package: Core
 type: module
 version: VERSION
 core_dependency: '^8.7'
+dependencies:
+  - goodness_api
+INVALID_CORE_DEPENDENCY;
+
+    vfsStream::setup('modules');
+    vfsStream::create([
+      'fixtures' => [
+        'invalid_core_dependency.info.txt' => $invalid_core_dependency,
+      ],
+    ]);
+    $filename = vfsStream::url('modules/fixtures/invalid_core_dependency.info.txt');
+    $this->expectException('\Drupal\Core\Extension\InfoParserException');
+    $this->expectExceptionMessage("The 'core_dependency' can not be used to specify compatibility specific version before 8.7.7 in vfs://modules/fixtures/invalid_core_dependency.info.txt");
+    $this->infoParser->parse($filename);
+  }
+
+  /**
+   * Tests that missing required key is detected.
+   *
+   * @covers ::parse
+   */
+  public function testInfoParserMissingKey() {
+    $missing_key = <<<MISSINGKEY
+# info.yml for testing missing type key.
+name: File
+description: 'Defines a file field type.'
+package: Core
+version: VERSION
+core: 8.x
 dependencies:
   - field
-COREDEPENDENCYINVALID;
+MISSINGKEY;
 
     vfsStream::setup('modules');
     vfsStream::create([
       'fixtures' => [
-        'core_dependency_invalid.info.txt' => $core_dependency_invalid,
+        'missing_key.info.txt' => $missing_key,
       ],
     ]);
-    $filename = vfsStream::url('modules/fixtures/core_dependency_invalid.info.txt');
+    $filename = vfsStream::url('modules/fixtures/missing_key.info.txt');
     $this->expectException('\Drupal\Core\Extension\InfoParserException');
-    $this->expectExceptionMessage("The 'core_dependency' can not be used to specify compatibility specific version before 8.7.7 in vfs://modules/fixtures/core_dependency_invalid.info.txt");
+    $this->expectExceptionMessage('Missing required keys (type) in vfs://modules/fixtures/missing_key.info.txt');
     $this->infoParser->parse($filename);
   }