Allow @psalm-variadic to denote functions that use func_call_args

src/Psalm/Checker/CommentChecker.php

@@ -56,7 +56,7 @@ class CommentChecker
 
     /**
      * @param  string $comment
-     * @psalm-return object-like{return_type:null|string,params:array<object-like{name:string,type:string},deprecated:bool,suppress:array<string>}
+     * @psalm-return object-like{return_type:null|string,params:array<object-like{name:string,type:string},deprecated:bool,suppress:array<string>,variadic:boolean}
      */
     public static function extractDocblockInfo($comment)
     {
@@ -108,6 +108,8 @@ class CommentChecker
             }
         }
 
+        $info['variadic'] = isset($comments['specials']['psalm-variadic']);
+
         return $info;
     }
 }

src/Psalm/Checker/FunctionChecker.php

@@ -22,6 +22,12 @@ class FunctionChecker extends FunctionLikeChecker
      * @var array<string,array<string,array<FunctionLikeParameter>>>
      */
     protected static $file_function_params = [];
+
+    /**
+     * @var array<string,bool>
+     */
+    protected static $variadic_functions = [];
+
     protected static $builtin_function_params = [];
     protected static $builtin_functions = [];
     protected static $call_map = null;
@@ -74,6 +80,16 @@ class FunctionChecker extends FunctionLikeChecker
         return self::$file_function_params[$file_name][$function_id];
     }
 
+    /**
+     * @param  string $function_id
+     * @param  string $file_name
+     * @return boolean
+     */
+    public static function isVariadic($function_id, $file_name)
+    {
+        return isset(self::$variadic_functions[$file_name][$function_id]);
+    }
+
     /**
      * @param  string $function_id
      * @return void
@@ -153,6 +169,10 @@ class FunctionChecker extends FunctionLikeChecker
             self::$deprecated_functions[$file_name][$function_id] = true;
         }
 
+        if ($docblock_info['variadic']) {
+            self::$variadic_functions[$file_name][$function_id] = true;
+        }
+
         $this->suppressed_issues = $docblock_info['suppress'];
 
         if ($config->use_docblock_types) {

src/Psalm/Checker/MethodChecker.php

@@ -53,6 +53,12 @@ class MethodChecker extends FunctionLikeChecker
     protected static $method_suppress = [];
     protected static $deprecated_methods = [];
 
+    /**
+     * A dictionary of variadic methods
+     * @var array<string,bool>
+     */
+    protected static $variadic_methods = [];
+
     const VISIBILITY_PUBLIC = 1;
     const VISIBILITY_PROTECTED = 2;
     const VISIBILITY_PRIVATE = 3;
@@ -82,6 +88,19 @@ class MethodChecker extends FunctionLikeChecker
         return self::$method_params[$method_id];
     }
 
+    /**
+     * @param  string $method_id
+     * @return boolean
+     */
+    public static function isVariadic($method_id)
+    {
+        self::registerClassMethod($method_id);
+
+        $method_id = self::getDeclaringMethodId($method_id);
+
+        return isset(self::$variadic_methods[$method_id]);
+    }
+
     /**
      * @param  string $method_id
      * @return Type\Union|null
@@ -237,6 +256,10 @@ class MethodChecker extends FunctionLikeChecker
                 self::$deprecated_methods[$method_id] = true;
             }
 
+            if ($docblock_info['variadic']) {
+                self::$variadic_methods[$method_id] = true;
+            }
+
             $this->suppressed_issues = $docblock_info['suppress'];
             self::$method_suppress[$method_id] = $this->suppressed_issues;
 
@@ -329,7 +352,8 @@ class MethodChecker extends FunctionLikeChecker
 
         $cased_method_id = $method_id;
         $method_parts = explode('::', $method_id);
-        $method_id = $method_parts[0] . '::' . strtolower($method_parts[1]);
+        $method_parts[1] = strtolower($method_parts[1]);
+        $method_id = implode('::', $method_parts);
 
         self::registerClassMethod($method_id);
 
@@ -337,6 +361,10 @@ class MethodChecker extends FunctionLikeChecker
             return true;
         }
 
+        if ($method_parts[1] === '__construct') {
+
+        }
+
         if (IssueBuffer::accepts(
             new UndefinedMethod('Method ' . $cased_method_id . ' does not exist', $file_name, $line_number),
             $suppresssed_issues

src/Psalm/Checker/StatementsChecker.php

@@ -3546,8 +3546,17 @@ class StatementsChecker
     {
         $function_params = null;
 
+        $is_variadic = false;
+
         if ($method_id) {
             $function_params = FunctionLikeChecker::getParamsById($method_id, $args, $this->file_name);
+
+            if (strpos($method_id, '::')) {
+                $is_variadic = MethodChecker::isVariadic($method_id);
+            }
+            else {
+                $is_variadic = FunctionChecker::isVariadic(strtolower($method_id), $this->file_name);
+            }
         }
 
         foreach ($args as $argument_offset => $arg) {
@@ -3640,7 +3649,10 @@ class StatementsChecker
         }
 
         if ($method_id) {
-            if (count($args) > count($function_params) && (!count($function_params) || $function_params[count($function_params) - 1]->name !== '...=')) {
+            if (!$is_variadic
+                && count($args) > count($function_params)
+                && (!count($function_params) || $function_params[count($function_params) - 1]->name !== '...=')
+            ) {
                 if (IssueBuffer::accepts(
                     new TooManyArguments('Too many arguments for method ' . ($cased_method_id ?: $method_id), $this->checked_file_name, $line_number),
                     $this->suppressed_issues