Allow equality to automatically determine equal ordering

Author: rtheunissen

Zend/tests/comparisons/compare-rhs-is-used.phpt

@@ -0,0 +1,28 @@
+--TEST--
+__compareTo: RHS operator should be considered even if LHS doesn't implement
+--FILE--
+<?php
+
+class A
+{
+    // Does not implement __compareTo
+}
+
+class B
+{
+    public function __compareTo($other)
+    {
+        echo "Comparing!\n";
+        return 1;
+    }
+}
+
+var_dump(new A <=> new B);
+var_dump(new B <=> new A);
+
+?>
+--EXPECTF--
+Comparing!
+int(-1)
+Comparing!
+int(1)

Zend/tests/comparisons/equals-only-auto-ordering.phpt

@@ -0,0 +1,17 @@
+--TEST--
+__equals: Equal values automatically have equal ordering
+--FILE--
+<?php
+include("setup.inc");
+
+$a = new Equatable(1);
+$b = new Equatable(1);
+
+/* Give $a a value that $b doesn't have so that default comparison would break. */
+$a->unique = 10;
+
+var_dump($a <=> $b);   
+
+?>
+--EXPECTF--
+int(0)

Zend/zend_operators.c

@@ -2043,6 +2043,15 @@ ZEND_API int ZEND_FASTCALL compare_function(zval *result, zval *op1, zval *op2)
 					if (Z_OBJ_HANDLER_P(op1, compare)(result, op1, op2) == SUCCESS) {
 						convert_compare_result_to_long(result);
 						return SUCCESS;
+					} else {
+						if (Z_OBJ_HANDLER_P(op1, equals)) {
+							if (Z_OBJ_HANDLER_P(op1, equals)(result, op1, op2) == SUCCESS) {
+								if (i_zend_is_true(result)) {
+									ZVAL_LONG(result, 0);
+									return SUCCESS;
+								}
+							}
+						}
 					}
 				}
 
@@ -2055,6 +2064,15 @@ ZEND_API int ZEND_FASTCALL compare_function(zval *result, zval *op1, zval *op2)
 						convert_compare_result_to_long(result);
 						Z_LVAL_P(result) *= -1;
 						return SUCCESS;
+					} else {
+						if (Z_OBJ_HANDLER_P(op2, equals)) {
+							if (Z_OBJ_HANDLER_P(op2, equals)(result, op2, op1) == SUCCESS) {
+								if (i_zend_is_true(result)) {
+									ZVAL_LONG(result, 0);
+									return SUCCESS;
+								}
+							}
+						}
 					}
 				}
 
@@ -2074,6 +2092,15 @@ ZEND_API int ZEND_FASTCALL compare_function(zval *result, zval *op1, zval *op2)
 					if (Z_OBJ_HANDLER_P(op1, compare) && Z_OBJ_HANDLER_P(op1, compare)(result, op1, op2) == SUCCESS) {
  						convert_compare_result_to_long(result);
  						return SUCCESS;
+ 					} else {
+ 						if (Z_OBJ_HANDLER_P(op1, equals)) {
+							if (Z_OBJ_HANDLER_P(op1, equals)(result, op1, op2) == SUCCESS) {
+								if (i_zend_is_true(result)) {
+									ZVAL_LONG(result, 0);
+									return SUCCESS;
+								}
+							}
+						}
  					}
 				}
 
@@ -2082,6 +2109,15 @@ ZEND_API int ZEND_FASTCALL compare_function(zval *result, zval *op1, zval *op2)
 						convert_compare_result_to_long(result);
 						Z_LVAL_P(result) *= -1;
  						return SUCCESS;
+ 					} else {
+ 						if (Z_OBJ_HANDLER_P(op2, equals)) {
+							if (Z_OBJ_HANDLER_P(op2, equals)(result, op2, op1) == SUCCESS) {
+								if (i_zend_is_true(result)) {
+									ZVAL_LONG(result, 0);
+									return SUCCESS;
+								}
+							}
+						}
  					}
 				}