Closes #4489

Author: sebastianbergmann

ChangeLog-9.4.md

@@ -2,6 +2,12 @@
 
 All notable changes of the PHPUnit 9.4 release series are documented in this file using the [Keep a CHANGELOG](https://keepachangelog.com/) principles.
 
+## [9.4.4] - 2020-MM-DD
+
+### Fixed
+
+* [#4489](https://github.com/sebastianbergmann/phpunit/issues/4489): Numeric group names are not handled correctly
+
 ## [9.4.3] - 2020-11-10
 
 ### Fixed
@@ -38,6 +44,7 @@ All notable changes of the PHPUnit 9.4 release series are documented in this fil
 
 * The PHPUnit XML configuration generator (that is invoked using the `--generate-configuration` CLI option) now asks for a cache directory (default: `.phpunit.cache`)
 
+[9.4.4]: https://github.com/sebastianbergmann/phpunit/compare/9.4.3...9.4
 [9.4.3]: https://github.com/sebastianbergmann/phpunit/compare/9.4.2...9.4.3
 [9.4.2]: https://github.com/sebastianbergmann/phpunit/compare/9.4.1...9.4.2
 [9.4.1]: https://github.com/sebastianbergmann/phpunit/compare/9.4.0...9.4.1

src/Framework/TestSuite.php

@@ -12,6 +12,7 @@
 use const PHP_EOL;
 use function array_diff;
 use function array_keys;
+use function array_map;
 use function array_merge;
 use function array_unique;
 use function basename;
@@ -78,7 +79,7 @@ class TestSuite implements IteratorAggregate, Reorderable, SelfDescribing, Test
     /**
      * The test groups of the test suite.
      *
-     * @var array
+     * @psalm-var array<string,list<Test>>
      */
     protected $groups = [];
 
@@ -556,10 +557,17 @@ public function getName(): string
 
     /**
      * Returns the test groups of the suite.
+     *
+     * @psalm-return list<string>
      */
     public function getGroups(): array
     {
-        return array_keys($this->groups);
+        return array_map(
+            static function ($key): string {
+                return (string) $key;
+            },
+            array_keys($this->groups)
+        );
     }
 
     public function getGroupDetails(): array

tests/_files/BankAccountTest.php

@@ -24,6 +24,7 @@ protected function setUp(): void
      * @covers BankAccount::getBalance
      * @group balanceIsInitiallyZero
      * @group specification
+     * @group 1234
      */
     public function testBalanceIsInitiallyZero(): void
     {

tests/end-to-end/list-groups.phpt

@@ -12,6 +12,7 @@ PHPUnit\TextUI\Command::main();
 PHPUnit %s by Sebastian Bergmann and contributors.
 
 Available test group(s):
+ - 1234
  - balanceCannotBecomeNegative
  - balanceIsInitiallyZero
  - specification