[12.x] Compilable for Validation Contract (#54882)

* Adds the compiled rules contract

* Transforms NestedRules to use a Contract

* style fix

Author: peterfox

src/Illuminate/Contracts/Validation/CompilableRules.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Illuminate\Contracts\Validation;
+
+interface CompilableRules
+{
+    /**
+     * Compile the object into usable rules.
+     *
+     * @param  string  $attribute
+     * @param  mixed  $value
+     * @param  mixed  $data
+     * @param  mixed  $context
+     * @return \stdClass
+     */
+    public function compile($attribute, $value, $data = null, $context = null);
+}

src/Illuminate/Validation/NestedRules.php

@@ -2,9 +2,9 @@
 
 namespace Illuminate\Validation;
 
-use Illuminate\Support\Arr;
+use Illuminate\Contracts\Validation\CompilableRules;
 
-class NestedRules
+class NestedRules implements CompilableRules
 {
     /**
      * The callback to execute.
@@ -37,22 +37,6 @@ public function compile($attribute, $value, $data = null, $context = null)
     {
         $rules = call_user_func($this->callback, $value, $attribute, $data, $context);
 
-        $parser = new ValidationRuleParser(
-            Arr::undot(Arr::wrap($data))
-        );
-
-        if (is_array($rules) && ! array_is_list($rules)) {
-            $nested = [];
-
-            foreach ($rules as $key => $rule) {
-                $nested[$attribute.'.'.$key] = $rule;
-            }
-
-            $rules = $nested;
-        } else {
-            $rules = [$attribute => $rules];
-        }
-
-        return $parser->explode(ValidationRuleParser::filterConditionalRules($rules, $data));
+        return Rule::compile($attribute, $rules, $data);
     }
 }

src/Illuminate/Validation/Rule.php

@@ -3,6 +3,7 @@
 namespace Illuminate\Validation;
 
 use Illuminate\Contracts\Support\Arrayable;
+use Illuminate\Support\Arr;
 use Illuminate\Support\Traits\Macroable;
 use Illuminate\Validation\Rules\ArrayRule;
 use Illuminate\Validation\Rules\Can;
@@ -244,4 +245,33 @@ public static function numeric()
     {
         return new Numeric;
     }
+
+    /**
+     * Compile a set of rules for an attribute.
+     *
+     * @param  string  $attribute
+     * @param  array  $rules
+     * @param  array|null  $data
+     * @return object|\stdClass
+     */
+    public static function compile($attribute, $rules, $data = null)
+    {
+        $parser = new ValidationRuleParser(
+            Arr::undot(Arr::wrap($data))
+        );
+
+        if (is_array($rules) && ! array_is_list($rules)) {
+            $nested = [];
+
+            foreach ($rules as $key => $rule) {
+                $nested[$attribute.'.'.$key] = $rule;
+            }
+
+            $rules = $nested;
+        } else {
+            $rules = [$attribute => $rules];
+        }
+
+        return $parser->explode(ValidationRuleParser::filterConditionalRules($rules, $data));
+    }
 }

src/Illuminate/Validation/ValidationRuleParser.php

@@ -3,6 +3,7 @@
 namespace Illuminate\Validation;
 
 use Closure;
+use Illuminate\Contracts\Validation\CompilableRules;
 use Illuminate\Contracts\Validation\InvokableRule;
 use Illuminate\Contracts\Validation\Rule as RuleContract;
 use Illuminate\Contracts\Validation\ValidationRule;
@@ -138,7 +139,7 @@ protected function prepareRule($rule, $attribute)
             return $rule;
         }
 
-        if ($rule instanceof NestedRules) {
+        if ($rule instanceof CompilableRules) {
             return $rule->compile(
                 $attribute, $this->data[$attribute] ?? null, Arr::dot($this->data), $this->data
             )->rules[$attribute];
@@ -164,7 +165,7 @@ protected function explodeWildcardRules($results, $attribute, $rules)
         foreach ($data as $key => $value) {
             if (Str::startsWith($key, $attribute) || (bool) preg_match('/^'.$pattern.'\z/', $key)) {
                 foreach ((array) $rules as $rule) {
-                    if ($rule instanceof NestedRules) {
+                    if ($rule instanceof CompilableRules) {
                         $context = Arr::get($this->data, Str::beforeLast($key, '.'));
 
                         $compiled = $rule->compile($key, $value, $data, $context);
@@ -238,7 +239,7 @@ protected function mergeRulesForAttribute($results, $attribute, $rules)
      */
     public static function parse($rule)
     {
-        if ($rule instanceof RuleContract || $rule instanceof NestedRules) {
+        if ($rule instanceof RuleContract || $rule instanceof CompilableRules) {
             return [$rule, []];
         }