优化Arr::mergeDeep

Author: yunwuxin

src/helper/Arr.php

@@ -356,9 +356,7 @@ public static function has($array, $keys)
      */
     public static function isAssoc(array $array)
     {
-        $keys = array_keys($array);
-
-        return array_keys($keys) !== $keys;
+        return !array_is_list($array);
     }
 
     /**
@@ -632,16 +630,30 @@ public static function wrap($value)
         return is_array($value) ? $value : [$value];
     }
 
+    /**
+     * Recursively merge arrays.
+     * If the value is an associative array, it will be merged recursively.
+     * If the value is an indexed array, it will be replaced entirely.
+     *
+     * @param array ...$arrays
+     * @return array
+     */
     public static function mergeDeep(array ...$arrays): array
     {
         $result = [];
         foreach ($arrays as $array) {
             foreach ($array as $key => $value) {
                 if (isset($result[$key]) && is_array($result[$key]) && is_array($value)) {
-                    $result[$key] = self::mergeDeep(
-                        $result[$key],
-                        $value
-                    );
+                    // 只有当两个数组都是关联数组时才递归合并
+                    if (self::isAssoc($result[$key]) && self::isAssoc($value)) {
+                        $result[$key] = self::mergeDeep(
+                            $result[$key],
+                            $value
+                        );
+                    } else {
+                        // 如果任一数组是索引数组，则直接覆盖
+                        $result[$key] = $value;
+                    }
                 } else {
                     $result[$key] = $value;
                 }

tests/IsAssocTest.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace Tests;
+
+use think\helper\Arr;
+
+class IsAssocTest extends TestCase
+{
+    public function testEmptyArray()
+    {
+        // 空数组不是关联数组
+        $this->assertFalse(Arr::isAssoc([]));
+    }
+
+    public function testSequentialArray()
+    {
+        // 顺序索引数组不是关联数组
+        $this->assertFalse(Arr::isAssoc([1, 2, 3]));
+        $this->assertFalse(Arr::isAssoc(['a', 'b', 'c']));
+        $this->assertFalse(Arr::isAssoc([null, false, true]));
+    }
+
+    public function testNonSequentialArray()
+    {
+        // 非顺序索引数组是关联数组
+        $this->assertTrue(Arr::isAssoc([1 => 'a', 0 => 'b'])); // 键顺序不是0,1
+        $this->assertTrue(Arr::isAssoc([1 => 'a', 2 => 'b'])); // 不是从0开始
+        $this->assertTrue(Arr::isAssoc([0 => 'a', 2 => 'b'])); // 不连续
+    }
+
+    public function testStringKeys()
+    {
+        // 字符串键的数组是关联数组
+        $this->assertTrue(Arr::isAssoc(['a' => 1, 'b' => 2]));
+        // 注意：PHP会将字符串数字键'0'、'1'自动转换为整数键0、1
+        // 所以这个实际上是顺序索引数组，不是关联数组
+        $this->assertFalse(Arr::isAssoc(['0' => 'a', '1' => 'b']));
+        $this->assertTrue(Arr::isAssoc(['a' => 'a', 0 => 'b'])); // 混合键
+    }
+
+    public function testMixedKeys()
+    {
+        // 混合键类型的数组是关联数组
+        $this->assertTrue(Arr::isAssoc([0 => 'a', 'b' => 'b']));
+        $this->assertTrue(Arr::isAssoc(['a' => 1, 2 => 'b']));
+    }
+
+}

tests/MergeDeepTest.php

@@ -0,0 +1,69 @@
+<?php
+
+namespace Tests;
+
+use think\helper\Arr;
+
+class MergeDeepTest extends TestCase
+{
+    public function testMergeDeepWithAssociativeArrays()
+    {
+        // 测试关联数组的递归合并
+        $array1 = ['a' => ['b' => 2], 'c' => 3];
+        $array2 = ['a' => ['b' => 4, 'd' => 5], 'e' => 6];
+        
+        $result = Arr::mergeDeep($array1, $array2);
+        
+        $expected = [
+            'a' => ['b' => 4, 'd' => 5],
+            'c' => 3,
+            'e' => 6
+        ];
+        
+        $this->assertEquals($expected, $result);
+    }
+    
+    public function testMergeDeepWithIndexedArrays()
+    {
+        // 测试索引数组的覆盖
+        $array1 = ['a' => [1, 2, 3], 'b' => 2];
+        $array2 = ['a' => [4, 5], 'c' => 3];
+        
+        $result = Arr::mergeDeep($array1, $array2);
+        
+        $expected = [
+            'a' => [4, 5],  // 索引数组应该被完全覆盖
+            'b' => 2,
+            'c' => 3
+        ];
+        
+        $this->assertEquals($expected, $result);
+    }
+    
+    public function testMergeDeepWithMixedArrays()
+    {
+        // 测试混合数组类型
+        $array1 = [
+            'a' => ['b' => 2, 'c' => 3],
+            'd' => [1, 2, 3],
+            'e' => 4
+        ];
+        
+        $array2 = [
+            'a' => ['b' => 5, 'f' => 6],
+            'd' => [7, 8],
+            'g' => 9
+        ];
+        
+        $result = Arr::mergeDeep($array1, $array2);
+        
+        $expected = [
+            'a' => ['b' => 5, 'c' => 3, 'f' => 6],  // 关联数组递归合并
+            'd' => [7, 8],  // 索引数组被覆盖
+            'e' => 4,
+            'g' => 9
+        ];
+        
+        $this->assertEquals($expected, $result);
+    }
+}