Fix UPGRADING and add iterable|object type redundancy test

Author: Girgias

UPGRADING

@@ -19,6 +19,18 @@ PHP 8.2 UPGRADE NOTES
 1. Backward Incompatible Changes
 ========================================
 
+- Core:
+  . The iterable type is now a built-in compile time alias for array|Traversable.
+    Error messages relating to iterable will therefore now use array|Traversable.
+    Type Reflection is preserved for single iterable (and ?iterable) to produce
+    a ReflectionNamedType with name iterable, however usage of iterable in
+    union types will be converted to array|Traversable.
+    This change also impacts the compile time type redundancy check, since
+    types of the form object|iterable will now emit a compile time error:
+    "Fatal error: Type Traversable|object|array| contains both object and a class type, which is redundant"
+    However, types of the form array|iterable are not affected since they
+    were already throwing a compile time redundancy error.
+
 - Date:
   . DateTime::createFromImmutable() now has a tentative return type of static,
     previously it was DateTime.
@@ -231,7 +243,7 @@ PHP 8.2 UPGRADE NOTES
 
 - OpenSSL:
   . openssl_cipher_key_length(): Returns a key length for the supplied
-    cipher.  
+    cipher.
 
 - Reflection:
   . ReflectionFunction::isAnonymous()
@@ -400,6 +412,10 @@ PHP 8.2 UPGRADE NOTES
   . CURL_VERSION_UNICODE (libcurl >= 7.72.0)
   . CURL_VERSION_ZSTD (libcurl >= 7.72.0)
 
+- DBA
+  . DBA_LMDB_USE_SUB_DIR
+  . DBA_LMDB_NO_SUB_DIR
+
 - Filter
   . FILTER_FLAG_GLOBAL_RANGE
 
@@ -538,13 +554,6 @@ PHP 8.2 UPGRADE NOTES
     which is mostly when the CLI finishes. It is however still possible to
     explicitly close those streams using fclose and similar.
 
-- Core:
-  . The iterable type is now a built-in compile time alias for array|Traversable.
-    Error messages relating to iterable will therefore now use array|Traversable.
-    Type Reflection is preserved for single iterable (and ?iterable) to produce
-    a ReflectionNamedType with name iterable, however usage of iterable in
-    union types will be converted to array|Traversable
-
 ========================================
 14. Performance Improvements
 ========================================

Zend/tests/type_declarations/iterable/iterable_alias_redundancy_array_1.phpt

@@ -0,0 +1,12 @@
+--TEST--
+iterable type with array should be redundant
+--FILE--
+<?php
+
+function bar(): array|iterable|null {
+    return null;
+}
+
+?>
+--EXPECTF--
+Fatal error: Duplicate type array is redundant in %s on line %d

Zend/tests/type_declarations/iterable/iterable_alias_redundancy_array_2.phpt

@@ -0,0 +1,12 @@
+--TEST--
+iterable type with array should be redundant
+--FILE--
+<?php
+
+function bar(): iterable|array|null {
+    return null;
+}
+
+?>
+--EXPECTF--
+Fatal error: Duplicate type array is redundant in %s on line %d

Zend/tests/type_declarations/iterable/iterable_alias_redundancy_iterable.phpt

@@ -0,0 +1,12 @@
+--TEST--
+iterable type with second iterable should be redundant
+--FILE--
+<?php
+
+function bar(): iterable|iterable|null {
+    return null;
+}
+
+?>
+--EXPECTF--
+Fatal error: Duplicate type array is redundant in %s on line %d

Zend/tests/type_declarations/iterable/iterable_alias_redundancy_object_1.phpt

@@ -0,0 +1,12 @@
+--TEST--
+iterable type with object should be redundant
+--FILE--
+<?php
+
+function bar(): iterable|object|null {
+    return null;
+}
+
+?>
+--EXPECTF--
+Fatal error: Type Traversable|object|array|null contains both object and a class type, which is redundant in %s on line %d

Zend/tests/type_declarations/iterable/iterable_alias_redundancy_object_2.phpt

@@ -0,0 +1,12 @@
+--TEST--
+iterable type with object should be redundant
+--FILE--
+<?php
+
+function bar(): object|iterable|null {
+    return null;
+}
+
+?>
+--EXPECTF--
+Fatal error: Type Traversable|object|array|null contains both object and a class type, which is redundant in %s on line %d