Fix false positive PhanUndeclaredVariable for too many params

NEWS.md

@@ -11,6 +11,7 @@ New features(Analysis):
 + Disable `simplify_ast` by default.
   Phan's analysis of compound conditions and assignments/negations in conditions has improved enough that it should no longer be necessary.
 + Import more specific phpdoc/real array return types for internal global functions from opcache.
++ Emit `PhanUndeclaredVariable` and other warnings about arguments when there are too many parameters for methods. (#3245)
 
 Maintenance:
 + Make `\Phan\Library\None` a singleton in internal uses.

src/Phan/AST/ArrowFunc.php

@@ -89,6 +89,13 @@ private function buildUses(Node $n) : void
                     }
                 }
                 return;
+            case ast\AST_CLASS:
+                foreach ($n->children['args']->children ?? [] as $child_node) {
+                    if ($child_node instanceof Node) {
+                        $this->buildUses($child_node);
+                    }
+                }
+                return;
         }
         foreach ($n->children as $child_node) {
             if ($child_node instanceof Node) {

src/Phan/AST/UnionTypeVisitor.php

@@ -1958,6 +1958,34 @@ public function visitConst(Node $node) : UnionType
         return UnionType::empty();
     }
 
+    /**
+     * @throws UnanalyzableException
+     */
+    public function visitClass(Node $node) : UnionType
+    {
+        if ($node->flags & ast\flags\CLASS_ANONYMOUS) {
+            $class_name =
+                (new ContextNode(
+                    $this->code_base,
+                    $this->context,
+                    $node
+                ))->getUnqualifiedNameForAnonymousClass();
+        } else {
+            $class_name = (string)$node->children['name'];
+        }
+
+        if (!$class_name) {
+            // Should only occur with --use-fallback-parser
+            throw new UnanalyzableException($node, "Class name cannot be empty");
+        }
+
+        // @phan-suppress-next-line PhanThrowTypeMismatchForCall
+        return FullyQualifiedClassName::fromStringInContext(
+            $class_name,
+            $this->context
+        )->asType()->asRealUnionType();
+    }
+
     /**
      * Visit a node with kind `\ast\AST_CLASS_CONST`
      *
@@ -2706,7 +2734,6 @@ public static function unionTypeFromClassNode(
         Context $context,
         $node
     ) : UnionType {
-
         // If this is a list, build a union type by
         // recursively visiting the child nodes
         if ($node instanceof Node

src/Phan/Analysis/ArgumentType.php

@@ -439,6 +439,12 @@ private static function analyzeParameterList(
 
             // This issue should be caught elsewhere
             if (!$parameter) {
+                $argument_type = UnionTypeVisitor::unionTypeFromNode(
+                    $code_base,
+                    $context,
+                    $argument,
+                    true
+                );
                 continue;
             }
 

tests/php74_files/expected/020_class.php.expected

@@ -0,0 +1,17 @@
+%s:2 PhanPluginUseReturnValueNoopVoid The function/method \accepts_one() is declared to return void and it has no side effects
+%s:2 PhanUnusedGlobalFunctionParameter Parameter $x is never used
+%s:7 PhanParamTooMany Call with 2 arg(s) to \accepts_one($x) which only takes 1 arg(s) defined at %s:2
+%s:7 PhanUndeclaredVariable Variable $a is undeclared
+%s:8 PhanParamTooManyInternal Call with 2 arg(s) to \strlen(string $string) which only takes 1 arg(s)
+%s:8 PhanUndeclaredVariable Variable $other is undeclared
+%s:10 PhanParamTooMany Call with 1 arg(s) to \anonymous_class_%s::__construct() which only takes 0 arg(s) defined at %s:10
+%s:10 PhanUndeclaredVariable Variable $invalid is undeclared
+%s:10 PhanUnusedVariable Unused definition of variable $x
+%s:13 PhanUndeclaredVariable Variable $z is undeclared
+%s:14 PhanParamTooMany Call with 2 arg(s) to \anonymous_class_%s::__construct($first) which only takes 1 arg(s) defined at %s:14
+%s:14 PhanUndeclaredVariable Variable $a is undeclared
+%s:14 PhanUndeclaredVariable Variable $b is undeclared
+%s:14 PhanUnusedPublicNoOverrideMethodParameter Parameter $first is never used
+%s:15 PhanParamTooMany Call with 2 arg(s) to \Test::no_args() which only takes 0 arg(s) defined at %s:4
+%s:16 PhanUndeclaredVariable Variable $c is undeclared
+%s:17 PhanUndeclaredVariable Variable $d is undeclared

tests/php74_files/src/020_class.php

@@ -0,0 +1,22 @@
+<?php
+function accepts_one($x) {}
+class Test {
+    public static function no_args() {}
+}
+call_user_func(function () {
+    accepts_one(1, $a);
+    echo strlen('x', $other);
+    // Should warn about missing $invalid
+    $x = new class ($invalid) {};
+    // Should warn about missing $a and $b (and PhanParamTooMany), but not $x
+    $fn = fn() => [
+        $z,
+        new class ($a, $b) { public function __construct($first) {} public static function test(int $x) { return $x;}},
+        Test::no_args(
+            $c,
+            $d
+        ),
+
+    ];
+    return $fn;
+});