Add test for isset/empty behaviour with all container types

This is a seperate part of the RFC, but to already have a test

Author: Girgias

Zend/tests/offsets/isset_empty_container_behaviour.phpt

@@ -0,0 +1,127 @@
+--TEST--
+Behaviour of isset()/empty() with various container types
+--FILE--
+<?php
+
+require_once __DIR__ . DIRECTORY_SEPARATOR . 'test_offset_helpers.inc';
+
+foreach ($allContainers as $container) {
+    echo zend_test_var_export($container), '[0]', "\n";
+
+    try {
+        var_dump(isset($container[0]));
+    } catch (Throwable $e) {
+        echo $e::class, ': ', $e->getMessage(), PHP_EOL;
+    }
+    try {
+        var_dump(empty($container[0]));
+    } catch (Throwable $e) {
+        echo $e::class, ': ', $e->getMessage(), PHP_EOL;
+    }
+}
+
+?>
+--EXPECT--
+NULL[0]
+bool(false)
+bool(true)
+false[0]
+bool(false)
+bool(true)
+true[0]
+bool(false)
+bool(true)
+4[0]
+bool(false)
+bool(true)
+5.5[0]
+bool(false)
+bool(true)
+'10'[0]
+bool(true)
+bool(false)
+'25.5'[0]
+bool(true)
+bool(false)
+'string'[0]
+bool(true)
+bool(false)
+[][0]
+bool(false)
+bool(true)
+STDERR[0]
+bool(false)
+bool(true)
+new stdClass()[0]
+Error: Cannot use object of type stdClass as array
+Error: Cannot use object of type stdClass as array
+new ArrayObject()[0]
+bool(false)
+bool(true)
+new A()[0]
+string(15) "A::offsetExists"
+int(0)
+string(12) "A::offsetGet"
+int(0)
+bool(true)
+string(15) "A::offsetExists"
+int(0)
+string(12) "A::offsetGet"
+int(0)
+bool(false)
+new B()[0]
+string(15) "B::offsetExists"
+int(0)
+string(12) "B::offsetGet"
+int(0)
+bool(true)
+string(15) "B::offsetExists"
+int(0)
+string(12) "B::offsetGet"
+int(0)
+bool(false)
+new DimensionRead()[0]
+string(27) "DimensionRead::offsetExists"
+int(0)
+string(24) "DimensionRead::offsetGet"
+int(0)
+bool(true)
+string(27) "DimensionRead::offsetExists"
+int(0)
+string(24) "DimensionRead::offsetGet"
+int(0)
+bool(false)
+new DimensionFetch()[0]
+string(27) "DimensionRead::offsetExists"
+int(0)
+string(24) "DimensionRead::offsetGet"
+int(0)
+bool(true)
+string(27) "DimensionRead::offsetExists"
+int(0)
+string(24) "DimensionRead::offsetGet"
+int(0)
+bool(false)
+new DimensionWrite()[0]
+Error: Cannot read offset of object of type DimensionWrite
+Error: Cannot read offset of object of type DimensionWrite
+new DimensionReadWrite()[0]
+string(32) "DimensionReadWrite::offsetExists"
+int(0)
+string(29) "DimensionReadWrite::offsetGet"
+int(0)
+bool(true)
+string(32) "DimensionReadWrite::offsetExists"
+int(0)
+string(29) "DimensionReadWrite::offsetGet"
+int(0)
+bool(false)
+new DimensionAppend()[0]
+Error: Cannot read offset of object of type DimensionAppend
+Error: Cannot read offset of object of type DimensionAppend
+new DimensionFetchAppend()[0]
+Error: Cannot read offset of object of type DimensionFetchAppend
+Error: Cannot read offset of object of type DimensionFetchAppend
+new DimensionUnset()[0]
+Error: Cannot read offset of object of type DimensionUnset
+Error: Cannot read offset of object of type DimensionUnset