From 3485984958fd82480d990e47a81ede1ee67170a3 Mon Sep 17 00:00:00 2001
From: Stanislav Eismont <stanislav.eismont@gmail.com>
Date: Mon, 28 Jun 2021 14:37:11 +0300
Subject: [PATCH] Add support for anonymous classes

---
 compiler/gentree.cpp                          | 73 ++++++++++++-------
 compiler/gentree.h                            |  5 +-
 compiler/lexer.cpp                            |  3 +-
 .../phpt/anon_classes/001_set_to_variable.php | 13 ++++
 .../anon_classes/002_pass_to_function.php     | 20 +++++
 .../003_constructor_arguments.php             | 21 ++++++
 .../004_access_to_outer_class.php             | 32 ++++++++
 tests/phpt/anon_classes/005_extend_traits.php | 24 ++++++
 .../006_anon_classes_equality.php             | 17 +++++
 .../007_constructor_type_mismatch.php         | 11 +++
 10 files changed, 192 insertions(+), 27 deletions(-)
 create mode 100644 tests/phpt/anon_classes/001_set_to_variable.php
 create mode 100644 tests/phpt/anon_classes/002_pass_to_function.php
 create mode 100644 tests/phpt/anon_classes/003_constructor_arguments.php
 create mode 100644 tests/phpt/anon_classes/004_access_to_outer_class.php
 create mode 100644 tests/phpt/anon_classes/005_extend_traits.php
 create mode 100644 tests/phpt/anon_classes/006_anon_classes_equality.php
 create mode 100644 tests/phpt/anon_classes/007_constructor_type_mismatch.php

diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 37c15588b1..d2f66a4206 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -223,10 +223,8 @@ VertexAdaptor<op_require> GenTree::get_require(bool once) {
 }
 
 template<Operation Op, Operation EmptyOp>
-VertexAdaptor<Op> GenTree::get_func_call() {
+VertexAdaptor<Op> GenTree::get_func_call(std::string name) {
   auto location = auto_location();
-  string name{cur->str_val};
-  next_cur();
 
   CE (expect(tok_oppar, "'('"));
   skip_phpdoc_tokens();
@@ -243,6 +241,28 @@ VertexAdaptor<Op> GenTree::get_func_call() {
   return call;
 }
 
+template<Operation Op, Operation EmptyOp>
+VertexAdaptor<Op> GenTree::get_func_call() {
+  string name{cur->str_val};
+  next_cur();
+  return get_func_call<Op, EmptyOp>(name);
+}
+
+VertexAdaptor<op_func_call> GenTree::get_type_and_args_of_new_expression() {
+  if (test_expect(tok_class)) {
+    // here we met anon class definition and probably constructor's arguments
+    return get_class({}, ClassType::klass, true);
+  }
+
+  CE(!kphp_error(cur->type() == tok_func_name, "Expected class name after new"));
+  auto func_call = get_func_call<op_func_call, op_none>();
+  // hack to be more compatible with php
+  if (func_call->str_val == "Memcache") {
+    func_call->set_string("McMemcache");
+  }
+  return func_call;
+}
+
 VertexAdaptor<op_array> GenTree::get_short_array() {
   auto location = auto_location();
   next_cur();
@@ -526,13 +546,7 @@ VertexPtr GenTree::get_expr_top(bool was_arrow) {
 
     case tok_new: {
       next_cur();
-      CE(!kphp_error(cur->type() == tok_func_name, "Expected class name after new"));
-      auto func_call = get_func_call<op_func_call, op_none>();
-      // Hack to be more compatible with php
-      if (func_call->str_val == "Memcache") {
-        func_call->set_string("McMemcache");
-      }
-
+      auto func_call = get_type_and_args_of_new_expression();
       res = gen_constructor_call_with_args(func_call->str_val, func_call->get_next()).set_location(func_call);
       CE(res);
       break;
@@ -1617,7 +1631,7 @@ void GenTree::parse_extends_implements() {
   }
 }
 
-VertexPtr GenTree::get_class(vk::string_view phpdoc_str, ClassType class_type) {
+VertexAdaptor<op_func_call> GenTree::get_class(vk::string_view phpdoc_str, ClassType class_type, bool is_anonymous) {
   ClassModifiers modifiers;
   if (test_expect(tok_abstract)) {
     modifiers.set_abstract();
@@ -1633,20 +1647,26 @@ VertexPtr GenTree::get_class(vk::string_view phpdoc_str, ClassType class_type) {
   CE(vk::any_of_equal(cur->type(), tok_class, tok_interface, tok_trait));
   next_cur();
 
-  CE (!kphp_error(test_expect(tok_func_name), "Class name expected"));
-
-  auto name_str = cur->str_val;
-  next_cur();
+  VertexAdaptor<op_func_call> res;
+  std::string class_name;
+  if (is_anonymous) {
+    class_name = gen_unique_name("anon_class", cur_function);
+    res = get_func_call<op_func_call, op_none>(class_name);
+  } else {
+    CE (!kphp_error(test_expect(tok_func_name), "Class name expected"));
+    class_name = std::string{cur->str_val.data(), cur->str_val.size()};
+    next_cur();
+  }
 
   std::string full_class_name;
   if (processing_file->namespace_name.empty() && phpdoc_tag_exists(phpdoc_str, php_doc_tag::kphp_tl_class)) {
     kphp_assert(processing_file->is_builtin());
-    full_class_name = G->settings().tl_namespace_prefix.get() + name_str;
+    full_class_name = G->settings().tl_namespace_prefix.get() + class_name;
   } else {
-    full_class_name = processing_file->namespace_name.empty() ? std::string{name_str} : processing_file->namespace_name + "\\" + name_str;
+    full_class_name = processing_file->namespace_name.empty() ? class_name : processing_file->namespace_name + "\\" + class_name;
   }
 
-  kphp_error(processing_file->namespace_uses.find(name_str) == processing_file->namespace_uses.end(),
+  kphp_error(processing_file->namespace_uses.find(class_name) == processing_file->namespace_uses.end(),
              "Class name is the same as one of 'use' at the top of the file");
 
   StackPushPop<ClassPtr> c_alive(class_stack, cur_class, ClassPtr(new ClassData()));
@@ -1660,7 +1680,7 @@ VertexPtr GenTree::get_class(vk::string_view phpdoc_str, ClassType class_type) {
   parse_extends_implements();
 
   auto name_vertex = VertexAdaptor<op_func_name>::create().set_location(auto_location());
-  name_vertex->str_val = static_cast<std::string>(name_str);
+  name_vertex->str_val = class_name;
 
   cur_class->file_id = processing_file;
   cur_class->set_name_and_src_name(full_class_name, phpdoc_str);    // with full namespaces and slashes
@@ -1686,7 +1706,7 @@ VertexPtr GenTree::get_class(vk::string_view phpdoc_str, ClassType class_type) {
     G->register_and_require_function(cur_function, parsed_os, true);  // push the class down the pipeline
   }
 
-  return {};
+  return res;
 }
 
 
@@ -2023,7 +2043,8 @@ VertexPtr GenTree::get_statement(vk::string_view phpdoc_str) {
       if (cur_function->type == FunctionData::func_class_holder) {
         return get_class_member(phpdoc_str);
       } else if (vk::any_of_equal(cur->type(), tok_final, tok_abstract)) {
-        return get_class(phpdoc_str, ClassType::klass);
+        get_class(phpdoc_str, ClassType::klass);
+        return {};
       }
       next_cur();
       kphp_error(0, "Unexpected access modifier outside of class body");
@@ -2153,13 +2174,15 @@ VertexPtr GenTree::get_statement(vk::string_view phpdoc_str) {
       return empty;
     }
     case tok_class:
-      return get_class(phpdoc_str, ClassType::klass);
+      get_class(phpdoc_str, ClassType::klass);
+      return {};
     case tok_interface:
-      return get_class(phpdoc_str, ClassType::interface);
+      get_class(phpdoc_str, ClassType::interface);
+      return {};
     case tok_trait: {
-      auto res = get_class(phpdoc_str, ClassType::trait);
+      get_class(phpdoc_str, ClassType::trait);
       kphp_error(processing_file->namespace_uses.empty(), "Usage of operator `use`(Aliasing/Importing) with traits is temporarily prohibited");
-      return res;
+      return {};
     }
     default: {
       auto res = get_expression();
diff --git a/compiler/gentree.h b/compiler/gentree.h
index e551d9b911..8dd49c0d69 100644
--- a/compiler/gentree.h
+++ b/compiler/gentree.h
@@ -103,7 +103,10 @@ class GenTree {
   VertexAdaptor<Op> get_conv();
   VertexAdaptor<op_require> get_require(bool once);
   template<Operation Op, Operation EmptyOp>
+  VertexAdaptor<Op> get_func_call(std::string name);
+  template<Operation Op, Operation EmptyOp>
   VertexAdaptor<Op> get_func_call();
+  VertexAdaptor<op_func_call> get_type_and_args_of_new_expression();
   VertexAdaptor<op_array> get_short_array();
   VertexAdaptor<op_string> get_string();
   VertexAdaptor<op_string_build> get_string_build();
@@ -143,7 +146,7 @@ class GenTree {
   static VertexAdaptor<op_func_call> gen_constructor_call_with_args(std::string allocated_class_name, std::vector<VertexPtr> args);
   static VertexAdaptor<op_func_call> gen_constructor_call_with_args(ClassPtr allocated_class, std::vector<VertexPtr> args);
 
-  VertexPtr get_class(vk::string_view phpdoc_str, ClassType class_type);
+  VertexAdaptor<op_func_call> get_class(vk::string_view phpdoc_str, ClassType class_type, bool is_anonymous = false);
   void parse_extends_implements();
 
   static VertexPtr process_arrow(VertexPtr lhs, VertexPtr rhs);
diff --git a/compiler/lexer.cpp b/compiler/lexer.cpp
index 3eb1daba91..325d7ede2d 100644
--- a/compiler/lexer.cpp
+++ b/compiler/lexer.cpp
@@ -211,7 +211,8 @@ void LexerData::hack_last_tokens() {
     return;
   }
 
-  if (are_last_tokens(tok_new, tok_func_name, except_token_tag<tok_oppar>{})) {
+  if (are_last_tokens(tok_new, tok_func_name, except_token_tag<tok_oppar>{}) ||
+      are_last_tokens(tok_new, tok_class, except_token_tag<tok_oppar>{})) {
     Token t = tokens.back();
     tokens.pop_back();
     tokens.emplace_back(tok_oppar);
diff --git a/tests/phpt/anon_classes/001_set_to_variable.php b/tests/phpt/anon_classes/001_set_to_variable.php
new file mode 100644
index 0000000000..561d61f35c
--- /dev/null
+++ b/tests/phpt/anon_classes/001_set_to_variable.php
@@ -0,0 +1,13 @@
+@ok
+<?php
+
+function test_set_to_variable() {
+  $a = new class {
+    function say_foo() {
+      echo "foo";
+    }
+  };
+  $a->say_foo();
+}
+
+test_set_to_variable();
diff --git a/tests/phpt/anon_classes/002_pass_to_function.php b/tests/phpt/anon_classes/002_pass_to_function.php
new file mode 100644
index 0000000000..19eee0b21c
--- /dev/null
+++ b/tests/phpt/anon_classes/002_pass_to_function.php
@@ -0,0 +1,20 @@
+@ok
+<?php
+
+interface I {
+  function say_foo();
+}
+
+function call_say_foo(I $i) {
+  $i->say_foo();
+}
+
+function test_pass_to_function() {
+  call_say_foo(new class implements I {
+    function say_foo() {
+      echo "foo";
+    }
+  });
+}
+
+test_pass_to_function();
diff --git a/tests/phpt/anon_classes/003_constructor_arguments.php b/tests/phpt/anon_classes/003_constructor_arguments.php
new file mode 100644
index 0000000000..96eee4d21a
--- /dev/null
+++ b/tests/phpt/anon_classes/003_constructor_arguments.php
@@ -0,0 +1,21 @@
+@ok
+<?php
+
+function test_one_ctor_arg() {
+  new class(77) {
+    function __construct($num) {
+      echo $num;
+    }
+  };
+}
+
+function test_two_ctor_arg() {
+  new class("foo", "bar") {
+    function __construct($s1, $s2) {
+      echo $s1, $s2;
+    }
+  };
+}
+
+test_one_ctor_arg();
+test_two_ctor_arg();
diff --git a/tests/phpt/anon_classes/004_access_to_outer_class.php b/tests/phpt/anon_classes/004_access_to_outer_class.php
new file mode 100644
index 0000000000..6995ac4a59
--- /dev/null
+++ b/tests/phpt/anon_classes/004_access_to_outer_class.php
@@ -0,0 +1,32 @@
+@ok
+<?php
+
+// example from https://www.php.net/manual/en/language.oop5.anonymous.php
+class Outer {
+  private $prop = 1;
+  protected $prop2 = 2;
+
+  protected function func1() {
+    return 3;
+  }
+
+  public function func2() {
+    return new class($this->prop) extends Outer {
+      private $prop3;
+
+      public function __construct($prop) {
+        $this->prop3 = $prop;
+      }
+
+      public function func3() {
+        return $this->prop2 + $this->prop3 + $this->func1();
+      }
+    };
+  }
+}
+
+function test_access_to_outer_class() {
+  echo (new Outer)->func2()->func3();
+}
+
+test_access_to_outer_class();
diff --git a/tests/phpt/anon_classes/005_extend_traits.php b/tests/phpt/anon_classes/005_extend_traits.php
new file mode 100644
index 0000000000..97049342c6
--- /dev/null
+++ b/tests/phpt/anon_classes/005_extend_traits.php
@@ -0,0 +1,24 @@
+@ok
+<?php
+
+class Base {
+  public function sayHello() {
+    echo 'Hello ';
+  }
+}
+
+trait SayWorld {
+  public function sayHello() {
+    parent::sayHello();
+    echo 'World!';
+  }
+}
+
+function test_extend_traits() {
+  $obj = new class extends Base {
+    use SayWorld;
+  };
+  $obj->sayHello();
+}
+
+test_extend_traits();
diff --git a/tests/phpt/anon_classes/006_anon_classes_equality.php b/tests/phpt/anon_classes/006_anon_classes_equality.php
new file mode 100644
index 0000000000..964ac29895
--- /dev/null
+++ b/tests/phpt/anon_classes/006_anon_classes_equality.php
@@ -0,0 +1,17 @@
+@ok
+<?php
+
+function get_anon_class() {
+    return new class {};
+}
+
+function get_another_anon_class() {
+    return new class {};
+}
+
+function test_anon_classes_equality() {
+  echo (get_class(get_anon_class()) === get_class(get_anon_class()));
+  echo (get_class(get_anon_class()) === get_class(get_another_anon_class()));
+}
+
+test_anon_classes_equality();
diff --git a/tests/phpt/anon_classes/007_constructor_type_mismatch.php b/tests/phpt/anon_classes/007_constructor_type_mismatch.php
new file mode 100644
index 0000000000..90fa9fc8fd
--- /dev/null
+++ b/tests/phpt/anon_classes/007_constructor_type_mismatch.php
@@ -0,0 +1,11 @@
+@kphp_should_fail
+/pass int to argument \$num of anon_class.*::__construct\nbut it's declared as @param string/
+<?php
+
+function test_constructor_type_mismatch() {
+  new class(42) {
+    function __construct(string $num) {}
+  };
+}
+
+test_constructor_type_mismatch();