[VarDumper][PhpUnitBridge] Fix color detection

Author: nicolas-grekas

Dumper/CliDumper.php

@@ -610,19 +610,30 @@ private function hasColorSupport($stream): bool
             return false;
         }
 
-        if ('Hyper' === getenv('TERM_PROGRAM')) {
+        // Detect msysgit/mingw and assume this is a tty because detection
+        // does not work correctly, see https://github.com/composer/composer/issues/9690
+        if (!@stream_isatty($stream) && !\in_array(strtoupper((string) getenv('MSYSTEM')), ['MINGW32', 'MINGW64'], true)) {
             return true;
         }
 
-        if (\DIRECTORY_SEPARATOR === '\\') {
-            return (\function_exists('sapi_windows_vt100_support')
-                && @sapi_windows_vt100_support($stream))
-                || false !== getenv('ANSICON')
-                || 'ON' === getenv('ConEmuANSI')
-                || 'xterm' === getenv('TERM');
+        if ('\\' === \DIRECTORY_SEPARATOR && @sapi_windows_vt100_support($stream)) {
+            return true;
+        }
+
+        if ('Hyper' === getenv('TERM_PROGRAM')
+            || false !== getenv('COLORTERM')
+            || false !== getenv('ANSICON')
+            || 'ON' === getenv('ConEmuANSI')
+        ) {
+            return true;
+        }
+
+        if ('dumb' === $term = (string) getenv('TERM')) {
+            return false;
         }
 
-        return stream_isatty($stream);
+        // See https://github.com/chalk/supports-color/blob/d4f413efaf8da045c5ab440ed418ef02dbb28bf1/index.js#L157
+        return preg_match('/^((screen|xterm|vt100|vt220|putty|rxvt|ansi|cygwin|linux).*)|(.*-256(color)?(-bce)?)$/', $term);
     }
 
     /**