Fix JSON object order comparision with numeric keys

src/Util/Json.php

@@ -12,9 +12,9 @@
 use const JSON_PRETTY_PRINT;
 use const JSON_UNESCAPED_SLASHES;
 use const JSON_UNESCAPED_UNICODE;
-use function count;
-use function is_array;
+use const SORT_STRING;
 use function is_object;
+use function is_scalar;
 use function json_decode;
 use function json_encode;
 use function json_last_error;
@@ -72,24 +72,31 @@ public static function canonicalize(string $json): array
      */
     private static function recursiveSort(mixed &$json): void
     {
-        if (!is_array($json)) {
-            // If the object is not empty, change it to an associative array
-            // so we can sort the keys (and we will still re-encode it
-            // correctly, since PHP encodes associative arrays as JSON objects.)
-            // But EMPTY objects MUST remain empty objects. (Otherwise we will
-            // re-encode it as a JSON array rather than a JSON object.)
-            // See #2919.
-            if (is_object($json) && count((array) $json) > 0) {
-                $json = (array) $json;
-            } else {
-                return;
-            }
+        // Nulls, empty arrays, and scalars need no further handling.
+        if (!$json || is_scalar($json)) {
+            return;
         }
 
-        ksort($json);
+        $isObject = is_object($json);
+
+        if ($isObject) {
+            // Objects need to be sorted during canonicalization to ensure
+            // correct comparsion since JSON objects are unordered. It must be
+            // kept as an object so that the value correctly stays as a JSON
+            // object instead of potentially being converted to an array. This
+            // approach ensures that numeric string JSON keys are preserved and
+            // don't risk being flattened due to PHP's array semantics.
+            // See #2919, #4584, #4674
+            $json = (array) $json;
+            ksort($json, SORT_STRING);
+        }
 
         foreach ($json as &$value) {
             self::recursiveSort($value);
         }
+
+        if ($isObject) {
+            $json = (object) $json;
+        }
     }
 }

tests/unit/Framework/Constraint/JsonMatchesTest.php

@@ -40,6 +40,14 @@ public static function provider(): array
                 '{"first":1, "second":"2"}',
             ],
 
+            'object fields with numeric keys are unordered' => [
+                true,
+                '',
+                '',
+                '{"0":null,"a":{},"b":[],"c":"1","d":1,"e":-1,"f":[1,2],"g":[2,1],"h":{"0":"0","1":"1","2":"2"}}',
+                '{"a":{},"d":1,"b":[],"e":-1,"0":null,"c":"1","f":[1,2],"h":{"2":"2","1":"1","0":"0"},"g":[2,1]}',
+            ],
+
             'child object fields are unordered' => [
                 true,
                 '',
@@ -198,6 +206,139 @@ public static function provider(): array
                 '["first", "second"]',
             ],
 
+            'objects with numeric keys are not arrays' => [
+                false,
+                'Failed asserting that \'[{}]\' matches JSON string "{"0":{}}".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+-{
+-    "0": {}
+-}
++[
++    {}
++]
+
+EOT,
+                '{"0":{}}',
+                '[{}]',
+            ],
+
+            'child array elements are ordered' => [
+                false,
+                'Failed asserting that \'{"a":{},"d":1,"b":[],"e":-1,"0":null,"c":"1","f":[2,1],"h":{"2":"2","1":"1","0":"0"},"g":[2,1]}\' matches JSON string "{"0":null,"a":{},"b":[],"c":"1","d":1,"e":-1,"f":[1,2],"g":[2,1],"h":{"0":"0","1":"1","2":"2"}}".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+     "d": 1,
+     "e": -1,
+     "f": [
+-        1,
+-        2
++        2,
++        1
+     ],
+     "g": [
+         2,
+
+EOT,
+                '{"0":null,"a":{},"b":[],"c":"1","d":1,"e":-1,"f":[1,2],"g":[2,1],"h":{"0":"0","1":"1","2":"2"}}',
+                '{"a":{},"d":1,"b":[],"e":-1,"0":null,"c":"1","f":[2,1],"h":{"2":"2","1":"1","0":"0"},"g":[2,1]}',
+            ],
+
+            'child object with numeric fields stay as object' => [
+                false,
+                'Failed asserting that \'{"a":{},"d":1,"b":[],"e":-1,"0":null,"c":"1","f":[1,2],"h":["0","1","2"],"g":[2,1]}\' matches JSON string "{"0":null,"a":{},"b":[],"c":"1","d":1,"e":-1,"f":[1,2],"g":[2,1],"h":{"0":"0","1":"1","2":"2"}}".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+         2,
+         1
+     ],
+-    "h": {
+-        "0": "0",
+-        "1": "1",
+-        "2": "2"
+-    }
++    "h": [
++        "0",
++        "1",
++        "2"
++    ]
+ }
+
+EOT,
+                '{"0":null,"a":{},"b":[],"c":"1","d":1,"e":-1,"f":[1,2],"g":[2,1],"h":{"0":"0","1":"1","2":"2"}}',
+                '{"a":{},"d":1,"b":[],"e":-1,"0":null,"c":"1","f":[1,2],"h":["0","1","2"],"g":[2,1]}',
+            ],
+
+            'nested arrays are ordered' => [
+                false,
+                'Failed asserting that \'[{"1":"1","0":"0"},{"2":"2","3":"3"}]\' matches JSON string "[[1,0],[2,3]]".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+ [
+-    [
+-        1,
+-        0
+-    ],
+-    [
+-        2,
+-        3
+-    ]
++    {
++        "0": "0",
++        "1": "1"
++    },
++    {
++        "2": "2",
++        "3": "3"
++    }
+ ]
+
+EOT,
+                '[[1,0],[2,3]]',
+                '[{"1":"1","0":"0"},{"2":"2","3":"3"}]',
+            ],
+
+            'child objects in arrays stay in order' => [
+                false,
+                'Failed asserting that \'[{"2":"2","3":"3"},{"1":"1","0":"0"}]\' matches JSON string "[{"0":"0","1":"1"},{"2":"2","3":"3"}]".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+ [
+     {
++        "2": "2",
++        "3": "3"
++    },
++    {
+         "0": "0",
+         "1": "1"
+-    },
+-    {
+-        "2": "2",
+-        "3": "3"
+     }
+ ]
+
+EOT,
+
+                '[{"0":"0","1":"1"},{"2":"2","3":"3"}]',
+                '[{"2":"2","3":"3"},{"1":"1","0":"0"}]',
+            ],
+
             'objects are not arrays' => [
                 false,
                 'Failed asserting that \'{}\' matches JSON string "[]".',
@@ -213,6 +354,30 @@ public static function provider(): array
                 '[]',
                 '{}',
             ],
+
+            'arrays are not objects' => [
+                false,
+                'Failed asserting that \'{}\' matches JSON string "[]".',
+                <<<'EOT'
+Failed asserting that two json values are equal.
+--- Expected
++++ Actual
+@@ @@
+-[]
++{}
+
+EOT,
+                '[]',
+                '{}',
+            ],
+
+            'objects in arrays are unordered' => [
+                true,
+                '',
+                '',
+                '[{"0":"0","1":"1"},{"2":"2","3":"3"}]',
+                '[{"1":"1","0":"0"},{"2":"2","3":"3"}]',
+            ],
         ];
     }