[9.x] Add ability to supply additional callbacks in Rule::when (#40730)

* Add ability to supply callbacks in conditional rules

* Revert call_user_func

* Spacing

Author: stevebauman

src/Illuminate/Validation/ConditionalRules.php

@@ -58,20 +58,26 @@ public function passes(array $data = [])
     /**
      * Get the rules.
      *
+     * @param  array  $data
      * @return array
      */
-    public function rules()
+    public function rules(array $data = [])
     {
-        return is_string($this->rules) ? explode('|', $this->rules) : $this->rules;
+        return is_string($this->rules)
+                    ? explode('|', $this->rules)
+                    : value($this->rules, new Fluent($data));
     }
 
     /**
      * Get the default rules.
      *
+     * @param  array  $data
      * @return array
      */
-    public function defaultRules()
+    public function defaultRules(array $data = [])
     {
-        return is_string($this->defaultRules) ? explode('|', $this->defaultRules) : $this->defaultRules;
+        return is_string($this->defaultRules)
+                    ? explode('|', $this->defaultRules)
+                    : value($this->defaultRules, new Fluent($data));
     }
 }

src/Illuminate/Validation/ValidationRuleParser.php

@@ -313,16 +313,16 @@ public static function filterConditionalRules($rules, array $data = [])
 
             if ($attributeRules instanceof ConditionalRules) {
                 return [$attribute => $attributeRules->passes($data)
-                                ? array_filter($attributeRules->rules())
-                                : array_filter($attributeRules->defaultRules()), ];
+                                ? array_filter($attributeRules->rules($data))
+                                : array_filter($attributeRules->defaultRules($data)), ];
             }
 
             return [$attribute => collect($attributeRules)->map(function ($rule) use ($data) {
                 if (! $rule instanceof ConditionalRules) {
                     return [$rule];
                 }
 
-                return $rule->passes($data) ? $rule->rules() : $rule->defaultRules();
+                return $rule->passes($data) ? $rule->rules($data) : $rule->defaultRules($data);
             })->filter()->flatten(1)->values()->all()];
         })->all();
     }

tests/Validation/ValidationRuleParserTest.php

@@ -20,6 +20,12 @@ public function testConditionalRulesAreProperlyExpandedAndFiltered()
             'city' => ['required', Rule::when(function (Fluent $input) {
                 return true;
             }, ['min:2'])],
+            'state' => ['required', Rule::when(true, function (Fluent $input) {
+                return 'min:2';
+            })],
+            'zip' => ['required', Rule::when(false, [], function (Fluent $input) {
+                return ['min:2'];
+            })],
         ]);
 
         $this->assertEquals([
@@ -29,6 +35,8 @@ public function testConditionalRulesAreProperlyExpandedAndFiltered()
             'username' => ['required', 'min:2'],
             'address' => ['required'],
             'city' => ['required', 'min:2'],
+            'state' => ['required', 'min:2'],
+            'zip' => ['required', 'min:2'],
         ], $rules);
     }