Zend: Add tests for offsets and containers (#12723)

Add various tests showcasing the behavioural variations of different offset types used on various container types in all possible operations:
 - Read
 - Write
 - Read Write
 - Appending
 - Unsetting
 - Existence checks with isset()/empty/null coalesce operator
 - Behaviour of nesting dimensions (e.g. $container[$offset1][$offset2])

Add a test to ensure compile time and runtime behaviour is identical for offsets.

Add an internal class that overloads the dimension object handlers to zend_test

Author: Girgias

Zend/tests/offsets/ArrayAccess_container_offset_behaviour.phpt

@@ -0,0 +1,132 @@
+--TEST--
+ArrayAccess containers behaviour with offsets
+--FILE--
+<?php
+
+require_once __DIR__ . DIRECTORY_SEPARATOR . 'test_offset_helpers.inc';
+
+const EXPECTED_OUTPUT = <<<OUTPUT
+Read before write:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+int(5)
+Write:
+string(12) "CLASS_NAME::offsetSet"
+VAR_DUMP_OF_OFFSET
+int(5)
+Read:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+int(5)
+Read-Write:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetSet"
+VAR_DUMP_OF_OFFSET
+int(25)
+isset():
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+bool(true)
+empty():
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+bool(false)
+null coalesce:
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+int(5)
+unset():
+string(14) "CLASS_NAME::offsetUnset"
+VAR_DUMP_OF_OFFSET
+Nested read:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+
+Warning: Trying to access array offset on int in %s on line 62
+NULL
+Nested write:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+
+Notice: Indirect modification of overloaded element of CLASS_NAME has no effect in %s on line 69
+Cannot use a scalar value as an array
+Nested Read-Write:
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+
+Notice: Indirect modification of overloaded element of CLASS_NAME has no effect in %s on line 76
+Cannot use a scalar value as an array
+Nested isset():
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+bool(false)
+Nested empty():
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+bool(true)
+Nested null coalesce:
+string(15) "CLASS_NAME::offsetExists"
+VAR_DUMP_OF_OFFSET
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+string(7) "default"
+Nested unset():
+string(12) "CLASS_NAME::offsetGet"
+VAR_DUMP_OF_OFFSET
+
+Notice: Indirect modification of overloaded element of CLASS_NAME has no effect in %s on line 102
+Cannot unset offset in a non-array variable
+
+OUTPUT;
+
+ob_start();
+foreach (['A', 'B'] as $class) {
+    foreach ($offsets as $dimension) {
+        $container = new $class();
+        $error = "(new $class())[" . zend_test_var_export($dimension) . '] has different outputs' . "\n";
+        ob_start();
+        var_dump($dimension);
+        $var_dump_output = ob_get_clean();
+
+        include $var_dim_filename;
+        $varOutput = ob_get_contents();
+        ob_clean();
+        $varOutput = str_replace(
+            [$var_dim_filename],
+            ['%s'],
+            $varOutput
+        );
+
+        $expected_output = str_replace(
+            ["VAR_DUMP_OF_OFFSET\n", "CLASS_NAME"],
+            [$var_dump_output, $class],
+            EXPECTED_OUTPUT
+        );
+
+        if ($varOutput !== $expected_output) {
+            file_put_contents(__DIR__ . DIRECTORY_SEPARATOR . "debug_ArrayAccess_container_{$failuresNb}.txt", $varOutput);
+            ++$failuresNb;
+            $failures[] = $error;
+        }
+        ++$testCasesTotal;
+    }
+}
+ob_end_clean();
+
+echo "Executed tests\n";
+if ($failures !== []) {
+    echo "Failures:\n" . implode($failures);
+}
+
+?>
+--EXPECT--
+Executed tests