Add support for NO_COLOR env var

src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php

@@ -357,6 +357,11 @@ class DeprecationErrorHandler
             return false;
         }
 
+        // Follow https://no-color.org/
+        if (isset($_SERVER['NO_COLOR']) || false !== getenv('NO_COLOR')) {
+            return false;
+        }
+
         if ('Hyper' === getenv('TERM_PROGRAM')) {
             return true;
         }

src/Symfony/Component/Console/CHANGELOG.md

@@ -13,6 +13,7 @@ CHANGELOG
  * deprecated returning `null` from `Command::execute()`, return `0` instead
  * Deprecated the `Application::renderException()` and `Application::doRenderException()` methods,
    use `renderThrowable()` and `doRenderThrowable()` instead.
+ * added support for the `NO_COLOR` env var (https://no-color.org/)
 
 4.3.0
 -----

src/Symfony/Component/Console/Output/StreamOutput.php

@@ -97,6 +97,11 @@ class StreamOutput extends Output
      */
     protected function hasColorSupport()
     {
+        // Follow https://no-color.org/
+        if (isset($_SERVER['NO_COLOR']) || false !== getenv('NO_COLOR')) {
+            return false;
+        }
+
         if ('Hyper' === getenv('TERM_PROGRAM')) {
             return true;
         }

src/Symfony/Component/VarDumper/CHANGELOG.md

@@ -10,6 +10,7 @@ CHANGELOG
  * added the stamps of a message after it is dispatched in `TraceableMessageBus` and `MessengerDataCollector` collected data
  * added `UuidCaster`
  * made all casters final
+ * added support for the `NO_COLOR` env var (https://no-color.org/)
 
 4.3.0
 -----

src/Symfony/Component/VarDumper/Dumper/CliDumper.php

@@ -582,6 +582,11 @@ class CliDumper extends AbstractDumper
             return false;
         }
 
+        // Follow https://no-color.org/
+        if (isset($_SERVER['NO_COLOR']) || false !== getenv('NO_COLOR')) {
+            return false;
+        }
+
         if ('Hyper' === getenv('TERM_PROGRAM')) {
             return true;
         }