From 9a8de31377212144c22b6b1061c72da50d2282d9 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Wed, 11 Jan 2023 07:16:32 +0300
Subject: [PATCH 1/8] Initial implementation of match

---
 compiler/debug.cpp                      |  1 +
 compiler/gentree.cpp                    | 72 +++++++++++++++++++++++++
 compiler/gentree.h                      |  3 ++
 compiler/keywords.gperf                 |  1 +
 compiler/pipes/gen-tree-postprocess.cpp | 69 ++++++++++++++++++++++++
 compiler/pipes/gen-tree-postprocess.h   |  3 ++
 compiler/token.h                        |  1 +
 compiler/vertex-desc.json               | 52 ++++++++++++++++++
 8 files changed, 202 insertions(+)

diff --git a/compiler/debug.cpp b/compiler/debug.cpp
index 795ed12fd9..91c469a800 100644
--- a/compiler/debug.cpp
+++ b/compiler/debug.cpp
@@ -61,6 +61,7 @@ std::string debugTokenName(TokenType t) {
     {tok_as, "tok_as"},
     {tok_case, "tok_case"},
     {tok_switch, "tok_switch"},
+    {tok_match, "tok_match"},
     {tok_class, "tok_class"},
     {tok_interface, "tok_interface"},
     {tok_trait, "tok_trait"},
diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 554095b140..280df266a0 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -19,6 +19,7 @@
 #include "compiler/name-gen.h"
 #include "compiler/phpdoc.h"
 #include "compiler/stage.h"
+#include "compiler/token.h"
 #include "compiler/type-hint.h"
 #include "compiler/utils/string-utils.h"
 #include "compiler/vertex.h"
@@ -651,6 +652,9 @@ VertexPtr GenTree::get_expr_top(bool was_arrow, const PhpDocComment *phpdoc) {
       res = get_func_call<op_tuple, op_err>();
       CE (!kphp_error(res.as<op_tuple>()->size(), "tuple() must have at least one argument"));
       break;
+    case tok_match:
+      res = get_match();
+      break;
     case tok_shape:
       res = get_shape();
       break;
@@ -1213,6 +1217,74 @@ VertexAdaptor<op_switch> GenTree::get_switch() {
   return VertexUtil::create_switch_vertex(cur_function, switch_condition.set_location(location), std::move(cases)).set_location(location);
 }
 
+
+VertexAdaptor<op_match_proxy> GenTree::get_match() {
+  const auto location = auto_location();
+  next_cur();
+  CE(expect(tok_oppar, "'('"));
+  skip_phpdoc_tokens();
+  const auto match_condition = get_expression();
+  CE(!kphp_error(match_condition, "Failed to parse 'match' expression"));
+  CE(expect(tok_clpar, "')'"));
+
+  CE(expect(tok_opbrc, "'{'"));
+  std::vector<VertexPtr> cases;
+  while (cur->type() != tok_clbrc) {
+    skip_phpdoc_tokens();
+    if (cur->type() == tok_comma) {
+      next_cur();
+      continue;
+    }
+
+    if (cur->type() == tok_default) {
+      // printf("%s: new default arm!\n", __FUNCTION__);
+      cases.emplace_back(get_match_default());
+    }
+    else {
+      // printf("%s: new ordinary arm!\n", __FUNCTION__);
+      cases.emplace_back(get_match_case());
+    }
+  }
+
+  CE(expect(tok_clbrc, "'}'"));
+
+  auto kek = VertexAdaptor<op_match_proxy>::create(match_condition, std::move(cases)).set_location(location);
+  kek.debugPrint();
+  return kek;
+}
+
+VertexAdaptor<op_match_case> GenTree::get_match_case() {
+  const auto location = auto_location();
+  std::vector<VertexPtr> arms;
+
+  VertexPtr cur_expr;
+  for (cur_expr = get_expression(); cur_expr->type() != op_double_arrow; cur_expr = get_expression()) {
+    cur_expr.debugPrint();
+    if (cur_expr) {
+      arms.emplace_back(cur_expr);
+    }
+    if (cur->type() == tok_comma) {
+      next_cur();
+      continue;
+    }
+  }
+
+  cur_expr.debugPrint();
+
+  if (const auto double_arrow = cur_expr.try_as<op_double_arrow>()) {
+    arms.emplace_back(double_arrow->key());
+    return VertexAdaptor<op_match_case>::create(VertexAdaptor<op_seq_comma>::create(arms), double_arrow->value()).set_location(location);
+  }
+  assert(false && "Unreachable!");
+  return {};
+}
+
+VertexAdaptor<op_match_default> GenTree::get_match_default() {
+  const auto location = auto_location();
+  next_cur();
+  CE(expect(tok_double_arrow, "'=>'"));
+  return VertexAdaptor<op_match_default>::create(get_expression()).set_location(location);
+}
 VertexAdaptor<op_shape> GenTree::get_shape() {
   auto location = auto_location();
 
diff --git a/compiler/gentree.h b/compiler/gentree.h
index 79c9c547e9..e73f52baef 100644
--- a/compiler/gentree.h
+++ b/compiler/gentree.h
@@ -102,6 +102,9 @@ class GenTree {
   VertexAdaptor<op_for> get_for();
   VertexAdaptor<op_do> get_do();
   VertexAdaptor<op_switch> get_switch();
+  VertexAdaptor<op_match_proxy> get_match();
+  VertexAdaptor<op_match_case> get_match_case();
+  VertexAdaptor<op_match_default> get_match_default();
   VertexAdaptor<op_shape> get_shape();
   VertexPtr get_phpdoc_inside_function();
   bool parse_cur_function_uses();
diff --git a/compiler/keywords.gperf b/compiler/keywords.gperf
index e1260987d0..dcc6b98d0f 100644
--- a/compiler/keywords.gperf
+++ b/compiler/keywords.gperf
@@ -28,6 +28,7 @@ Array, tok_array
 as, tok_as
 case, tok_case
 switch, tok_switch
+match, tok_match
 class, tok_class
 interface, tok_interface
 trait, tok_trait
diff --git a/compiler/pipes/gen-tree-postprocess.cpp b/compiler/pipes/gen-tree-postprocess.cpp
index ddd9b2a94b..9014d71743 100644
--- a/compiler/pipes/gen-tree-postprocess.cpp
+++ b/compiler/pipes/gen-tree-postprocess.cpp
@@ -8,7 +8,11 @@
 #include "compiler/data/class-data.h"
 #include "compiler/data/lib-data.h"
 #include "compiler/data/src-file.h"
+#include "compiler/data/vertex-adaptor.h"
+#include "compiler/name-gen.h"
+#include "compiler/vertex-meta_op_base.h"
 #include "compiler/vertex-util.h"
+#include <vector>
 
 namespace {
 template <typename F>
@@ -230,6 +234,10 @@ VertexPtr GenTreePostprocessPass::on_enter_vertex(VertexPtr root) {
 }
 
 VertexPtr GenTreePostprocessPass::on_exit_vertex(VertexPtr root) {
+  if (current_function->name == "foo" && root->type() == op_function) {
+    root.debugPrint();
+  }
+  
   if (root->type() == op_var) {
     if (VertexUtil::is_superglobal(root->get_string())) {
       root->extra_type = op_ex_var_superglobal;
@@ -247,6 +255,10 @@ VertexPtr GenTreePostprocessPass::on_exit_vertex(VertexPtr root) {
     return convert_array_with_spread_operators(array);
   }
 
+  if (auto match = root.try_as<op_match_proxy>()) {
+    return convert_match(match);
+  }
+
   return root;
 }
 
@@ -311,3 +323,60 @@ VertexPtr GenTreePostprocessPass::convert_array_with_spread_operators(VertexAdap
 
   return call;
 }
+
+VertexPtr GenTreePostprocessPass::convert_match(VertexAdaptor<op_match_proxy> match_vertex) {
+  auto gen_superlocal = [&](const std::string& name_prefix) {
+    auto v = VertexAdaptor<op_var>::create().set_location(match_vertex);
+    v->str_val = gen_unique_name(name_prefix);
+    v->extra_type = op_ex_var_superlocal;
+    return v;
+  };
+
+  const auto tmp_result_var = gen_superlocal("tmp_result_of_match");
+  const auto match_condition = match_vertex->condition();
+  const auto tmp_condition_stored = gen_superlocal("tmp_condition_stored");
+  const auto matched_with_one = gen_superlocal("matched_with_one");
+  const auto cases = match_vertex->cases();
+
+  std::vector<VertexPtr> switch_arms;
+  bool has_default = false;
+  switch_arms.reserve(cases.size());
+
+  static const auto case_break = VertexAdaptor<op_break>::create(VertexUtil::create_int_const(1));
+  
+  for (const auto match_case : cases) {
+    // match_case.debugPrint();
+    if (const auto ordinary_case = match_case.try_as<op_match_case>()) {
+      // puts("Have hew ordinary case!\n");
+      const auto set_result = VertexAdaptor<op_set>::create(tmp_result_var, ordinary_case->result_expr());
+      const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{set_result, case_break.clone()}).set_location(ordinary_case);
+      for (const auto case_condition : ordinary_case->conditions()->args()) {
+        // puts("\tHave new condition!\n");
+        switch_arms.emplace_back(VertexAdaptor<op_case>::create(case_condition, case_body));
+      }
+    }
+    else if (const auto default_case = match_case.try_as<op_match_default>()) {
+      has_default = true;
+      const auto set_result = VertexAdaptor<op_set>::create(tmp_result_var, default_case->result_expr());
+      const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{set_result, case_break.clone()}).set_location(default_case);
+      switch_arms.emplace_back(VertexAdaptor<op_default>::create(case_body));
+    }
+    else {
+      // TODO error
+    }
+  }
+
+  if (!has_default) {
+    auto message = VertexAdaptor<op_string>::create();
+    message->str_val = "UnhandledMatchError!";
+    auto emit_error = VertexAdaptor<op_func_call>::create(std::vector{message});
+    emit_error->set_string("warning");
+    const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{emit_error, case_break.clone()});
+    switch_arms.emplace_back(VertexAdaptor<op_default>::create(case_body));
+  }
+
+  auto switch_vertex = VertexAdaptor<op_switch>::create(match_condition, tmp_condition_stored, matched_with_one, switch_arms);
+  switch_vertex->is_match = true;
+
+  return  VertexAdaptor<op_seq_rval>::create(switch_vertex, tmp_result_var);
+}
diff --git a/compiler/pipes/gen-tree-postprocess.h b/compiler/pipes/gen-tree-postprocess.h
index 0828172abb..87cf549f5b 100644
--- a/compiler/pipes/gen-tree-postprocess.h
+++ b/compiler/pipes/gen-tree-postprocess.h
@@ -23,4 +23,7 @@ class GenTreePostprocessPass final : public FunctionPassBase {
 
   // converts the spread operator (...$a) to a call to the array_merge_spread function
   static VertexPtr convert_array_with_spread_operators(VertexAdaptor<op_array> array_vertex);
+  // converts match to a statement expression that contains a switch operator and temporary variable
+  static VertexPtr convert_match(VertexAdaptor<op_match_proxy> match_vertex);
+
 };
diff --git a/compiler/token.h b/compiler/token.h
index 8303527035..7251bec1fe 100644
--- a/compiler/token.h
+++ b/compiler/token.h
@@ -44,6 +44,7 @@ enum TokenType {
   tok_as,
   tok_case,
   tok_switch,
+  tok_match,
   tok_class,
   tok_interface,
   tok_trait,
diff --git a/compiler/vertex-desc.json b/compiler/vertex-desc.json
index 0db7e0733c..20b82411e9 100644
--- a/compiler/vertex-desc.json
+++ b/compiler/vertex-desc.json
@@ -734,6 +734,10 @@
     "extra_fields": {
       "kind": {
         "type": "SwitchKind"
+      },
+      "is_match": {
+        "type" : "bool",
+        "default" : "false"
       }
     },
     "ranges": {
@@ -743,6 +747,54 @@
       ]
     }
   },
+  {
+    "comment": "match (condition()) { cases()... }",
+    "sons": {
+      "condition": 0
+    },
+    "name": "op_match_proxy",
+    "base_name": "meta_op_cycle",
+    "props": {
+      "str": "match",
+      "rl": "rl_other"
+    },
+    "ranges": {
+      "cases": [
+        1,
+        0
+      ]
+    }
+  },
+  {
+    "comment": "$expr_1, ..., $expr_n => $result_expr",
+    "sons": {
+      "conditions" : {
+        "id": 0,
+        "type": "op_seq_comma"
+      },
+      "result_expr" : {
+        "id": 1
+      }
+    },
+    "name": "op_match_case",
+    "base_name": "meta_op_base",
+    "props": {
+      "str": "case"
+    }
+  },
+  {
+    "comment": "default => $result_expr",
+    "sons": {
+      "result_expr" : {
+        "id": 0
+      }
+    },
+    "name": "op_match_default",
+    "base_name": "meta_op_base",
+    "props": {
+      "str": "default"
+    }
+  },
   {
     "comment": "if (cond()) true_cmd(); or if (cond()) true_cmd() else false_cmd()",
     "sons": {

From e1370a4bcee319c603bcf6defb01a47b122d356a Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Thu, 12 Jan 2023 06:44:32 +0300
Subject: [PATCH 2/8] Add tests from previous attempt; fix corner cases

---
 compiler/code-gen/vertex-compiler.cpp         |  2 +-
 compiler/gentree.cpp                          | 33 +++++++++----
 compiler/pipes/collect-main-edges.cpp         |  4 ++
 tests/phpt/php8/match/001_simple.php          | 22 +++++++++
 tests/phpt/php8/match/002_several_cases.php   | 13 +++++
 ...003_several_cases_with_different_types.php | 10 ++++
 tests/phpt/php8/match/004_several_in_case.php |  9 ++++
 .../php8/match/005_expression_as_case.php     | 13 +++++
 .../match/006_several_expression_as_case.php  | 19 ++++++++
 ...007_string_condition_in_only_int_cases.php |  9 ++++
 ...008_int_condition_in_only_string_cases.php |  9 ++++
 tests/phpt/php8/match/009_print_bool.php      | 12 +++++
 tests/phpt/php8/match/010_default_case.php    | 15 ++++++
 .../php8/match/011_bool_expression_cases.php  | 20 ++++++++
 .../phpt/php8/match/012_discarding_result.php | 11 +++++
 tests/phpt/php8/match/013_implicit_break.php  | 12 +++++
 .../php8/match/014_strict_comparisons.php     | 29 +++++++++++
 .../015_strict_comparisons_jump_table.php     | 48 +++++++++++++++++++
 ...016_strict_comparisons_true_expression.php | 14 ++++++
 ...17_strict_comparisons_false_expression.php | 14 ++++++
 .../match/018_mixed_int_string_jump_table.php | 29 +++++++++++
 ...9_match_expression_with_trailing_comma.php | 22 +++++++++
 tests/phpt/php8/match/020_bad_case.php        |  7 +++
 .../php8/match/021_several_default_arm.php    |  8 ++++
 .../php8/match/022_repeated_conditions.php    |  9 ++++
 .../phpt/php8/match/023_unhandeled_value.php  |  8 ++++
 .../php8/match/024_unhandeled_array_value.php | 14 ++++++
 tests/phpt/php8/match/025_arrays.php          | 13 +++++
 28 files changed, 417 insertions(+), 11 deletions(-)
 create mode 100644 tests/phpt/php8/match/001_simple.php
 create mode 100644 tests/phpt/php8/match/002_several_cases.php
 create mode 100644 tests/phpt/php8/match/003_several_cases_with_different_types.php
 create mode 100644 tests/phpt/php8/match/004_several_in_case.php
 create mode 100644 tests/phpt/php8/match/005_expression_as_case.php
 create mode 100644 tests/phpt/php8/match/006_several_expression_as_case.php
 create mode 100644 tests/phpt/php8/match/007_string_condition_in_only_int_cases.php
 create mode 100644 tests/phpt/php8/match/008_int_condition_in_only_string_cases.php
 create mode 100644 tests/phpt/php8/match/009_print_bool.php
 create mode 100644 tests/phpt/php8/match/010_default_case.php
 create mode 100644 tests/phpt/php8/match/011_bool_expression_cases.php
 create mode 100644 tests/phpt/php8/match/012_discarding_result.php
 create mode 100644 tests/phpt/php8/match/013_implicit_break.php
 create mode 100644 tests/phpt/php8/match/014_strict_comparisons.php
 create mode 100644 tests/phpt/php8/match/015_strict_comparisons_jump_table.php
 create mode 100644 tests/phpt/php8/match/016_strict_comparisons_true_expression.php
 create mode 100644 tests/phpt/php8/match/017_strict_comparisons_false_expression.php
 create mode 100644 tests/phpt/php8/match/018_mixed_int_string_jump_table.php
 create mode 100644 tests/phpt/php8/match/019_match_expression_with_trailing_comma.php
 create mode 100644 tests/phpt/php8/match/020_bad_case.php
 create mode 100644 tests/phpt/php8/match/021_several_default_arm.php
 create mode 100644 tests/phpt/php8/match/022_repeated_conditions.php
 create mode 100644 tests/phpt/php8/match/023_unhandeled_value.php
 create mode 100644 tests/phpt/php8/match/024_unhandeled_array_value.php
 create mode 100644 tests/phpt/php8/match/025_arrays.php

diff --git a/compiler/code-gen/vertex-compiler.cpp b/compiler/code-gen/vertex-compiler.cpp
index 1ffdd2fb8b..3eecf3805e 100644
--- a/compiler/code-gen/vertex-compiler.cpp
+++ b/compiler/code-gen/vertex-compiler.cpp
@@ -1211,7 +1211,7 @@ void compile_switch_var(VertexAdaptor<op_switch> root, CodeGenerator &W) {
     VertexAdaptor<op_seq> cmd;
     if (auto cs = one_case.try_as<op_case>()) {
       cmd = cs->cmd();
-      W << "if (" << temp_var_matched_with_a_case << " || eq2(" << temp_var_condition_on_switch << ", " << cs->expr() << ")) " << BEGIN;
+      W << "if (" << temp_var_matched_with_a_case << " || " << (root->is_match ? "equals(" : "eq2(") << temp_var_condition_on_switch << ", " << cs->expr() << ")) " << BEGIN;
       W << temp_var_matched_with_a_case << " = true;" << NL;
     } else {
       if (!default_case_is_the_last) {
diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 280df266a0..b42a336f72 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -14,6 +14,7 @@
 #include "compiler/data/function-data.h"
 #include "compiler/data/lib-data.h"
 #include "compiler/data/src-file.h"
+#include "compiler/data/vertex-adaptor.h"
 #include "compiler/lambda-utils.h"
 #include "compiler/lexer.h"
 #include "compiler/name-gen.h"
@@ -1244,6 +1245,7 @@ VertexAdaptor<op_match_proxy> GenTree::get_match() {
       // printf("%s: new ordinary arm!\n", __FUNCTION__);
       cases.emplace_back(get_match_case());
     }
+    kphp_assert_msg(cases.back(), "Invalid 'match' case!");
   }
 
   CE(expect(tok_clbrc, "'}'"));
@@ -1258,30 +1260,41 @@ VertexAdaptor<op_match_case> GenTree::get_match_case() {
   std::vector<VertexPtr> arms;
 
   VertexPtr cur_expr;
-  for (cur_expr = get_expression(); cur_expr->type() != op_double_arrow; cur_expr = get_expression()) {
-    cur_expr.debugPrint();
-    if (cur_expr) {
-      arms.emplace_back(cur_expr);
-    }
+  for (cur_expr = get_expression(); cur_expr && cur_expr->type() != op_double_arrow; cur_expr = get_expression()) {
+    arms.emplace_back(cur_expr);
+  
     if (cur->type() == tok_comma) {
       next_cur();
       continue;
     }
   }
 
-  cur_expr.debugPrint();
+  VertexPtr result;
 
-  if (const auto double_arrow = cur_expr.try_as<op_double_arrow>()) {
+  // trailling comma: "fourty-two", => 42'
+  if (!cur_expr) {
+    CE(expect(tok_double_arrow, "'=>'"));
+    result = get_expression();
+  }
+  else if (const auto double_arrow = cur_expr.try_as<op_double_arrow>()) {
     arms.emplace_back(double_arrow->key());
-    return VertexAdaptor<op_match_case>::create(VertexAdaptor<op_seq_comma>::create(arms), double_arrow->value()).set_location(location);
+    result = double_arrow->value();
   }
-  assert(false && "Unreachable!");
-  return {};
+  else {
+    kphp_fail_msg("Ivalid syntax of 'match' cases!");
+  }
+  
+  return VertexAdaptor<op_match_case>::create(VertexAdaptor<op_seq_comma>::create(arms), result).set_location(location);
 }
 
 VertexAdaptor<op_match_default> GenTree::get_match_default() {
   const auto location = auto_location();
   next_cur();
+
+  // trailling comma: default, => 42'
+  if (cur->type() == tok_comma) {
+    next_cur();
+  }
   CE(expect(tok_double_arrow, "'=>'"));
   return VertexAdaptor<op_match_default>::create(get_expression()).set_location(location);
 }
diff --git a/compiler/pipes/collect-main-edges.cpp b/compiler/pipes/collect-main-edges.cpp
index e4d4597f14..5b0abdb485 100644
--- a/compiler/pipes/collect-main-edges.cpp
+++ b/compiler/pipes/collect-main-edges.cpp
@@ -9,6 +9,7 @@
 #include "compiler/data/src-file.h"
 #include "compiler/data/var-data.h"
 #include "compiler/function-pass.h"
+#include "compiler/vertex-meta_op_base.h"
 #include "compiler/vertex-util.h"
 #include "compiler/inferring/edge.h"
 #include "compiler/inferring/ifi.h"
@@ -49,6 +50,9 @@ SwitchKind get_switch_kind(VertexAdaptor<op_switch> s) {
     return SwitchKind::EmptySwitch;
   }
 
+  if (s->is_match) {
+    return SwitchKind::VarSwitch;
+  }
   if (num_const_string_cases == num_value_cases) {
     return SwitchKind::StringSwitch;
   } else if (num_const_int_cases == num_value_cases) {
diff --git a/tests/phpt/php8/match/001_simple.php b/tests/phpt/php8/match/001_simple.php
new file mode 100644
index 0000000000..2b0018fe0f
--- /dev/null
+++ b/tests/phpt/php8/match/001_simple.php
@@ -0,0 +1,22 @@
+@ok php8
+<?php
+
+function wordify($x) {
+  return match ($x) {
+    0 => 'Zero',
+    1 => 'One',
+    2 => 'Two',
+    3 => 'Three',
+    4 => 'Four',
+    5 => 'Five',
+    6 => 'Six',
+    7 => 'Seven',
+    8 => 'Eight',
+    9 => 'Nine',
+    default => 'default',
+  };
+}
+
+for ($i = 0; $i <= 9; $i++) {
+  echo wordify($i) . "\n";
+}
diff --git a/tests/phpt/php8/match/002_several_cases.php b/tests/phpt/php8/match/002_several_cases.php
new file mode 100644
index 0000000000..141c891f05
--- /dev/null
+++ b/tests/phpt/php8/match/002_several_cases.php
@@ -0,0 +1,13 @@
+@ok php8
+<?php
+
+function is_working_day($day) {
+  return match ($day) {
+    1, 7 => false,
+    2, 3, 4, 5, 6 => true,
+  };
+}
+
+for ($i = 1; $i <= 7; $i++) {
+  var_dump(is_working_day($i));
+}
diff --git a/tests/phpt/php8/match/003_several_cases_with_different_types.php b/tests/phpt/php8/match/003_several_cases_with_different_types.php
new file mode 100644
index 0000000000..d3f278ea4a
--- /dev/null
+++ b/tests/phpt/php8/match/003_several_cases_with_different_types.php
@@ -0,0 +1,10 @@
+@ok php8
+<?php
+
+$a = "hello";
+
+var_dump(match ($a) {
+  10 => "oops, error",
+  "hello" => "ok",
+  default => "oops, default",
+});
diff --git a/tests/phpt/php8/match/004_several_in_case.php b/tests/phpt/php8/match/004_several_in_case.php
new file mode 100644
index 0000000000..cf43bb891a
--- /dev/null
+++ b/tests/phpt/php8/match/004_several_in_case.php
@@ -0,0 +1,9 @@
+@ok php8
+<?php
+
+$a = 20;
+
+var_dump(match ($a) {
+  10, 20, 30 => "ok",
+  default => "oops, default",
+});
diff --git a/tests/phpt/php8/match/005_expression_as_case.php b/tests/phpt/php8/match/005_expression_as_case.php
new file mode 100644
index 0000000000..559cc08403
--- /dev/null
+++ b/tests/phpt/php8/match/005_expression_as_case.php
@@ -0,0 +1,13 @@
+@ok php8
+<?php
+
+function f() {
+  return 20;
+}
+
+$a = 20;
+
+var_dump(match ($a) {
+  f() => "ok",
+  default => "oops, default",
+});
diff --git a/tests/phpt/php8/match/006_several_expression_as_case.php b/tests/phpt/php8/match/006_several_expression_as_case.php
new file mode 100644
index 0000000000..b2a384a66f
--- /dev/null
+++ b/tests/phpt/php8/match/006_several_expression_as_case.php
@@ -0,0 +1,19 @@
+@ok php8
+<?php
+
+function f1() {
+  return 20;
+}
+
+function f2() {
+  echo "oops, shouldn't have been called\n";
+  return 10;
+}
+
+$a = 20;
+
+var_dump(match ($a) {
+  f1() => "ok",
+  f2() => "oops",
+  default => "oops, default",
+});
diff --git a/tests/phpt/php8/match/007_string_condition_in_only_int_cases.php b/tests/phpt/php8/match/007_string_condition_in_only_int_cases.php
new file mode 100644
index 0000000000..db56422e75
--- /dev/null
+++ b/tests/phpt/php8/match/007_string_condition_in_only_int_cases.php
@@ -0,0 +1,9 @@
+@ok php8
+<?php
+
+$a = "10";
+
+var_dump(match ($a) {
+  10 => "oops, type casting",
+  default => "ok",
+});
diff --git a/tests/phpt/php8/match/008_int_condition_in_only_string_cases.php b/tests/phpt/php8/match/008_int_condition_in_only_string_cases.php
new file mode 100644
index 0000000000..e67ba96c5f
--- /dev/null
+++ b/tests/phpt/php8/match/008_int_condition_in_only_string_cases.php
@@ -0,0 +1,9 @@
+@ok php8
+<?php
+
+$a = 10;
+
+var_dump(match ($a) {
+  "10" => "oops, type casting",
+  default => "ok",
+});
diff --git a/tests/phpt/php8/match/009_print_bool.php b/tests/phpt/php8/match/009_print_bool.php
new file mode 100644
index 0000000000..1289c69477
--- /dev/null
+++ b/tests/phpt/php8/match/009_print_bool.php
@@ -0,0 +1,12 @@
+@ok php8
+<?php
+
+function print_bool($bool) {
+  echo match ($bool) {
+    true => "true\n",
+    false => "false\n"
+  };
+}
+
+print_bool(true);
+print_bool(false);
diff --git a/tests/phpt/php8/match/010_default_case.php b/tests/phpt/php8/match/010_default_case.php
new file mode 100644
index 0000000000..62a2c22c4e
--- /dev/null
+++ b/tests/phpt/php8/match/010_default_case.php
@@ -0,0 +1,15 @@
+@ok php8
+<?php
+
+function get_value($i) {
+  return match ($i) {
+    1 => 1,
+    2 => 2,
+    default => 'default',
+  };
+}
+
+echo get_value(0) . "\n";
+echo get_value(1) . "\n";
+echo get_value(2) . "\n";
+echo get_value(3) . "\n";
diff --git a/tests/phpt/php8/match/011_bool_expression_cases.php b/tests/phpt/php8/match/011_bool_expression_cases.php
new file mode 100644
index 0000000000..5ca7d97490
--- /dev/null
+++ b/tests/phpt/php8/match/011_bool_expression_cases.php
@@ -0,0 +1,20 @@
+@ok php8
+<?php
+
+function get_range($i) {
+  return match (true) {
+    $i >= 50 => '50+',
+    $i >= 40 => '40-50',
+    $i >= 30 => '30-40',
+    $i >= 20 => '20-30',
+    $i >= 10 => '10-20',
+    default => '0-10',
+  };
+}
+
+echo get_range(22) . "\n";
+echo get_range(0) . "\n";
+echo get_range(59) . "\n";
+echo get_range(13) . "\n";
+echo get_range(39) . "\n";
+echo get_range(40) . "\n";
diff --git a/tests/phpt/php8/match/012_discarding_result.php b/tests/phpt/php8/match/012_discarding_result.php
new file mode 100644
index 0000000000..3f3a289a3f
--- /dev/null
+++ b/tests/phpt/php8/match/012_discarding_result.php
@@ -0,0 +1,11 @@
+@ok php8
+<?php
+
+function print_this() {
+  echo "Executed\n";
+  return 0;
+}
+
+match (1) {
+  1 => print_this(),
+};
diff --git a/tests/phpt/php8/match/013_implicit_break.php b/tests/phpt/php8/match/013_implicit_break.php
new file mode 100644
index 0000000000..36f135cc92
--- /dev/null
+++ b/tests/phpt/php8/match/013_implicit_break.php
@@ -0,0 +1,12 @@
+@ok php8
+<?php
+
+function dump_and_return($string) {
+  var_dump($string);
+  return $string;
+}
+
+var_dump(match ('foo') {
+  'foo' => dump_and_return('foo'),
+  'bar' => dump_and_return('bar'),
+});
diff --git a/tests/phpt/php8/match/014_strict_comparisons.php b/tests/phpt/php8/match/014_strict_comparisons.php
new file mode 100644
index 0000000000..cc95ee6f36
--- /dev/null
+++ b/tests/phpt/php8/match/014_strict_comparisons.php
@@ -0,0 +1,29 @@
+@ok php8
+<?php
+
+function wrong() {
+  return "wrong";
+}
+
+var_dump(match (0) {
+  null => wrong(),
+  false => wrong(),
+  0.0 => wrong(),
+  [] => wrong(),
+  '' => wrong(),
+  0 => 'int',
+});
+
+function get_value2() {
+  return 0;
+}
+
+var_dump(match (get_value2()) {
+  null => wrong(),
+  false => wrong(),
+  0.0 => wrong(),
+  [] => wrong(),
+  '' => wrong(),
+  0 => 'int',
+  default => 'default',
+});
diff --git a/tests/phpt/php8/match/015_strict_comparisons_jump_table.php b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
new file mode 100644
index 0000000000..3206638307
--- /dev/null
+++ b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
@@ -0,0 +1,48 @@
+@ok php8
+<?php
+
+function wrong() {
+  return "wrong";
+}
+
+function test_int($char) {
+  return match ($char) {
+    0 => wrong(),
+    1 => wrong(),
+    2 => wrong(),
+    3 => wrong(),
+    4 => wrong(),
+    5 => wrong(),
+    6 => wrong(),
+    7 => wrong(),
+    8 => wrong(),
+    9 => wrong(),
+    default => 'Not matched',
+  };
+}
+
+foreach (range(0, 9) as $int) {
+  var_dump((string)$int);
+  var_dump(test_int((string)$int));
+}
+
+function test_string($int) {
+  return match ($int) {
+    '0' => wrong(),
+    '1' => wrong(),
+    '2' => wrong(),
+    '3' => wrong(),
+    '4' => wrong(),
+    '5' => wrong(),
+    '6' => wrong(),
+    '7' => wrong(),
+    '8' => wrong(),
+    '9' => wrong(),
+    default => 'Not matched',
+  };
+}
+
+foreach (range(0, 9) as $int) {
+  var_dump($int);
+  var_dump(test_string($int));
+}
diff --git a/tests/phpt/php8/match/016_strict_comparisons_true_expression.php b/tests/phpt/php8/match/016_strict_comparisons_true_expression.php
new file mode 100644
index 0000000000..9f0fcf4fd9
--- /dev/null
+++ b/tests/phpt/php8/match/016_strict_comparisons_true_expression.php
@@ -0,0 +1,14 @@
+@ok php8
+<?php
+
+function wrong() {
+  return "wrong";
+}
+
+echo match (true) {
+  'truthy' => wrong(),
+  ['truthy'] => wrong(),
+  1 => wrong(),
+  1.0 => wrong(),
+  true => "true\n",
+};
diff --git a/tests/phpt/php8/match/017_strict_comparisons_false_expression.php b/tests/phpt/php8/match/017_strict_comparisons_false_expression.php
new file mode 100644
index 0000000000..1e256d6364
--- /dev/null
+++ b/tests/phpt/php8/match/017_strict_comparisons_false_expression.php
@@ -0,0 +1,14 @@
+@ok php8
+<?php
+
+function wrong() {
+  return "wrong";
+}
+
+echo match (false) {
+  '' => wrong(),
+  [] => wrong(),
+  0 => wrong(),
+  0.0 => wrong(),
+  false => "false\n",
+};
diff --git a/tests/phpt/php8/match/018_mixed_int_string_jump_table.php b/tests/phpt/php8/match/018_mixed_int_string_jump_table.php
new file mode 100644
index 0000000000..ea8fcd4521
--- /dev/null
+++ b/tests/phpt/php8/match/018_mixed_int_string_jump_table.php
@@ -0,0 +1,29 @@
+@ok php8
+<?php
+
+function test($value) {
+  echo match ($value) {
+    1 => '1 int',
+    '1' => '1 string',
+    2 => '2 int',
+    '2' => '2 string',
+    3 => '3 int',
+    '3' => '3 string',
+    4 => '4 int',
+    '4' => '4 string',
+    5 => '5 int',
+    '5' => '5 string',
+  };
+  echo "\n";
+}
+
+test(1);
+test('1');
+test(2);
+test('2');
+test(3);
+test('3');
+test(4);
+test('4');
+test(5);
+test('5');
diff --git a/tests/phpt/php8/match/019_match_expression_with_trailing_comma.php b/tests/phpt/php8/match/019_match_expression_with_trailing_comma.php
new file mode 100644
index 0000000000..d6dbc50e36
--- /dev/null
+++ b/tests/phpt/php8/match/019_match_expression_with_trailing_comma.php
@@ -0,0 +1,22 @@
+@ok php8
+<?php
+
+function print_bool($bool) {
+  echo match ($bool) {
+    false,
+    0,
+    => "false\n",
+    true,
+    1,
+    => "true\n",
+    default,
+    => "not bool\n",
+  };
+}
+
+print_bool(false);
+print_bool(0);
+print_bool(true);
+print_bool(1);
+print_bool(2);
+print_bool('foo');
diff --git a/tests/phpt/php8/match/020_bad_case.php b/tests/phpt/php8/match/020_bad_case.php
new file mode 100644
index 0000000000..4e9e58ffa8
--- /dev/null
+++ b/tests/phpt/php8/match/020_bad_case.php
@@ -0,0 +1,7 @@
+@kphp_should_fail php8
+/Expected expression before token '=>'/
+<?php
+
+match(10) {
+   => "ok",
+};
diff --git a/tests/phpt/php8/match/021_several_default_arm.php b/tests/phpt/php8/match/021_several_default_arm.php
new file mode 100644
index 0000000000..a6f2898713
--- /dev/null
+++ b/tests/phpt/php8/match/021_several_default_arm.php
@@ -0,0 +1,8 @@
+@kphp_should_fail php8
+/Match expressions may only contain one default arm/
+<?php
+
+match(10) {
+   default => "default",
+   default => "default",
+};
diff --git a/tests/phpt/php8/match/022_repeated_conditions.php b/tests/phpt/php8/match/022_repeated_conditions.php
new file mode 100644
index 0000000000..7ddcf4c847
--- /dev/null
+++ b/tests/phpt/php8/match/022_repeated_conditions.php
@@ -0,0 +1,9 @@
+@kphp_should_fail php8
+/Repeated case \[10\] in switch\/match/
+<?php
+
+match(10) {
+   10, 20 => "1",
+   10 => "2",
+   default => "default",
+};
diff --git a/tests/phpt/php8/match/023_unhandeled_value.php b/tests/phpt/php8/match/023_unhandeled_value.php
new file mode 100644
index 0000000000..a16a939dec
--- /dev/null
+++ b/tests/phpt/php8/match/023_unhandeled_value.php
@@ -0,0 +1,8 @@
+@kphp_runtime_should_warn php8
+/Unhandled match value '100'/
+<?php
+
+match(100) {
+   10, 20 => "1",
+   30 => "2",
+};
diff --git a/tests/phpt/php8/match/024_unhandeled_array_value.php b/tests/phpt/php8/match/024_unhandeled_array_value.php
new file mode 100644
index 0000000000..14c7509276
--- /dev/null
+++ b/tests/phpt/php8/match/024_unhandeled_array_value.php
@@ -0,0 +1,14 @@
+@kphp_runtime_should_warn php8
+/Unhandled match value 'Array/
+<?php
+
+$options = [
+    'monthly',
+    'credit-card1',
+];
+
+echo match ($options) {
+    ['monthly', 'direct-debit'] => 1,
+    ['yearly', 'credit-card']   => 2,
+    ['monthly', 'credit-card']  => 3,
+};
diff --git a/tests/phpt/php8/match/025_arrays.php b/tests/phpt/php8/match/025_arrays.php
new file mode 100644
index 0000000000..a6c5290d47
--- /dev/null
+++ b/tests/phpt/php8/match/025_arrays.php
@@ -0,0 +1,13 @@
+@ok php8
+<?php
+
+$options = [
+    'monthly',
+    'credit-card',
+];
+
+echo match ($options) {
+    ['monthly', 'direct-debit'] => 1,
+    ['yearly', 'credit-card']   => 2,
+    ['monthly', 'credit-card']  => 3,
+};

From 4b74386d59a1ca43a3330d883321d3f252197245 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Mon, 16 Jan 2023 17:34:58 +0300
Subject: [PATCH 3/8] Complete task

---
 compiler/code-gen/vertex-compiler.cpp         | 36 +++++++++++++++---
 compiler/gentree.cpp                          |  2 +
 compiler/pipes/collect-main-edges.cpp         | 20 ++++++++--
 compiler/pipes/gen-tree-postprocess.cpp       |  4 +-
 .../015_strict_comparisons_jump_table.php     | 38 +++++++++----------
 tests/phpt/php8/match/020_bad_case.php        |  2 +-
 .../php8/match/021_several_default_arm.php    |  2 +-
 .../php8/match/022_repeated_conditions.php    |  2 +-
 .../phpt/php8/match/023_unhandeled_value.php  |  2 +-
 .../php8/match/024_unhandeled_array_value.php |  1 -
 10 files changed, 74 insertions(+), 35 deletions(-)

diff --git a/compiler/code-gen/vertex-compiler.cpp b/compiler/code-gen/vertex-compiler.cpp
index 3eecf3805e..242964baca 100644
--- a/compiler/code-gen/vertex-compiler.cpp
+++ b/compiler/code-gen/vertex-compiler.cpp
@@ -4,6 +4,7 @@
 
 #include "compiler/code-gen/vertex-compiler.h"
 
+#include "compiler/inferring/primitive-type.h"
 #include <iterator>
 #include <unordered_map>
 
@@ -1119,8 +1120,12 @@ void compile_switch_str(VertexAdaptor<op_switch> root, CodeGenerator &W) {
   auto temp_var_strval_of_condition = root->condition_on_switch();
   auto temp_var_matched_with_a_case = root->matched_with_one_case();
 
+  // because we checked types before in case of match
+  const auto *const convert_function = root->is_match ? "" : "f$strval";
+
+
   W << BEGIN;
-  W << temp_var_strval_of_condition << " = f$strval (" << root->condition() << ");" << NL;
+  W << temp_var_strval_of_condition << " = " << convert_function << "(" << root->condition() << ");" << NL;
   W << temp_var_matched_with_a_case << " = false;" << NL;
 
   W << "switch (" << temp_var_strval_of_condition << ".hash()) " << BEGIN;
@@ -1163,7 +1168,9 @@ void compile_switch_str(VertexAdaptor<op_switch> root, CodeGenerator &W) {
 }
 
 void compile_switch_int(VertexAdaptor<op_switch> root, CodeGenerator &W) {
-  W << "switch (f$intval (" << root->condition() << "))" << BEGIN;
+  // because we checked types before in case of match
+  const auto *const convert_function = root->is_match ? "" : "f$intval";
+  W << "switch (" << convert_function << " (" << root->condition() << "))" << BEGIN;
 
   W << "static_cast<void>(" << root->condition_on_switch() << ");" << NL;
   W << "static_cast<void>(" << root->matched_with_one_case() << ");" << NL;
@@ -1178,7 +1185,8 @@ void compile_switch_int(VertexAdaptor<op_switch> root, CodeGenerator &W) {
       if (val->type() == op_int_const) {
         const std::string &str = val.as<op_int_const>()->str_val;
         W << str;
-        kphp_error(used.insert(str).second, fmt_format("Switch: repeated cases found [{}]", str));
+        const std::string op = root->is_match ? "Match" : "Switch";
+        kphp_error(used.insert(str).second, fmt_format("{}: repeated cases found [{}]", op, str));
       } else {
         kphp_assert(VertexUtil::is_const_int(val));
         W << val;
@@ -1200,6 +1208,7 @@ void compile_switch_var(VertexAdaptor<op_switch> root, CodeGenerator &W) {
 
   auto temp_var_condition_on_switch = root->condition_on_switch();
   auto temp_var_matched_with_a_case = root->matched_with_one_case();
+  const auto *const eq_function = root->is_match ? "equals" : "eq2";
 
   W << "do " << BEGIN;
   W << temp_var_condition_on_switch << " = " << root->condition() << ";" << NL;
@@ -1211,7 +1220,7 @@ void compile_switch_var(VertexAdaptor<op_switch> root, CodeGenerator &W) {
     VertexAdaptor<op_seq> cmd;
     if (auto cs = one_case.try_as<op_case>()) {
       cmd = cs->cmd();
-      W << "if (" << temp_var_matched_with_a_case << " || " << (root->is_match ? "equals(" : "eq2(") << temp_var_condition_on_switch << ", " << cs->expr() << ")) " << BEGIN;
+      W << "if (" << temp_var_matched_with_a_case << " || " << eq_function << "(" << temp_var_condition_on_switch << ", " << cs->expr() << ")) " << BEGIN;
       W << temp_var_matched_with_a_case << " = true;" << NL;
     } else {
       if (!default_case_is_the_last) {
@@ -1250,12 +1259,29 @@ void compile_switch(VertexAdaptor<op_switch> root, CodeGenerator &W) {
 
   for (auto one_case : root->cases()) {
     if (one_case->type() == op_default) {
-      kphp_error_return(!has_default, "Switch: several `default` cases found");
+      const std::string op = root->is_match ? "Match" : "Switch";
+      kphp_error_return(!has_default, op + ": several `default` cases found");
       has_default = true;
       continue;
     }
   }
 
+  if (root->is_match) {
+    const auto *const cond_type = tinf::get_type(root->condition());
+     if (!cond_type) {
+      compile_switch_var(root, W);
+      return;
+    }
+
+    if (root->kind == SwitchKind::StringSwitch && cond_type->get_real_ptype() == tp_string) {
+      compile_switch_str(root, W);
+    } else if (root->kind == SwitchKind::IntSwitch &&  cond_type->get_real_ptype() == tp_int) {
+      compile_switch_int(root, W);
+    } else {
+      compile_switch_var(root, W);
+    }
+    return;
+  }
   if (root->kind == SwitchKind::StringSwitch) {
     compile_switch_str(root, W);
   } else if (root->kind == SwitchKind::IntSwitch) {
diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index b42a336f72..15efdc26a5 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -15,6 +15,7 @@
 #include "compiler/data/lib-data.h"
 #include "compiler/data/src-file.h"
 #include "compiler/data/vertex-adaptor.h"
+#include "compiler/kphp_assert.h"
 #include "compiler/lambda-utils.h"
 #include "compiler/lexer.h"
 #include "compiler/name-gen.h"
@@ -1274,6 +1275,7 @@ VertexAdaptor<op_match_case> GenTree::get_match_case() {
   // trailling comma: "fourty-two", => 42'
   if (!cur_expr) {
     CE(expect(tok_double_arrow, "'=>'"));
+    kphp_error(!arms.empty(), "Expected expression before '=>'");
     result = get_expression();
   }
   else if (const auto double_arrow = cur_expr.try_as<op_double_arrow>()) {
diff --git a/compiler/pipes/collect-main-edges.cpp b/compiler/pipes/collect-main-edges.cpp
index 5b0abdb485..a8ee0e485b 100644
--- a/compiler/pipes/collect-main-edges.cpp
+++ b/compiler/pipes/collect-main-edges.cpp
@@ -27,6 +27,7 @@ SwitchKind get_switch_kind(VertexAdaptor<op_switch> s) {
   int num_const_int_cases = 0;
   int num_const_string_cases = 0;
   int num_value_cases = 0;
+  int num_const_total_string_cases = 0;
 
   for (auto one_case : s->cases()) {
     if (one_case->type() == op_default) {
@@ -38,6 +39,8 @@ SwitchKind get_switch_kind(VertexAdaptor<op_switch> s) {
     if (VertexUtil::is_const_int(val)) {
       num_const_int_cases++;
     } else if (auto as_string = val.try_as<op_string>()) {
+      // In case of op_switch node that was generated from op_match
+      num_const_total_string_cases++;
       // PHP would use a numerical comparison for strings that look like a number,
       // we shouldn't rewrite these switches as a string-only switch
       if (!php_is_numeric(as_string->str_val.data())) {
@@ -49,13 +52,13 @@ SwitchKind get_switch_kind(VertexAdaptor<op_switch> s) {
   if (num_value_cases == 0) {
     return SwitchKind::EmptySwitch;
   }
-
-  if (s->is_match) {
-    return SwitchKind::VarSwitch;
+  if (s->is_match && num_const_total_string_cases == num_value_cases) {
+    return SwitchKind::StringSwitch;
   }
   if (num_const_string_cases == num_value_cases) {
     return SwitchKind::StringSwitch;
-  } else if (num_const_int_cases == num_value_cases) {
+  }
+  if (num_const_int_cases == num_value_cases) {
     return SwitchKind::IntSwitch;
   }
   return SwitchKind::VarSwitch;
@@ -408,6 +411,15 @@ void CollectMainEdgesPass::on_switch(VertexAdaptor<op_switch> switch_op) {
   // int-only and string-only switches separately (these simple switch statements
   // form a majority of all switch statements)
   switch_op->kind = get_switch_kind(switch_op);
+  if (switch_op->is_match) {
+    // in case of converted from op_match
+    create_set(as_lvalue(switch_op->condition_on_switch()->var_id), switch_op->condition());
+    for (const auto &c : switch_op->cases()) {
+      if (auto as_case = c.try_as<op_case>()) {
+        create_set(as_lvalue(switch_op->condition_on_switch()->var_id), as_case->expr());
+      }
+    }
+  }
   if (switch_op->kind == SwitchKind::IntSwitch) {
     // in case of int-only switch, condition var is discarded, so there is
     // no real need in trying to insert an assignment node here
diff --git a/compiler/pipes/gen-tree-postprocess.cpp b/compiler/pipes/gen-tree-postprocess.cpp
index 9014d71743..fbba525914 100644
--- a/compiler/pipes/gen-tree-postprocess.cpp
+++ b/compiler/pipes/gen-tree-postprocess.cpp
@@ -368,9 +368,9 @@ VertexPtr GenTreePostprocessPass::convert_match(VertexAdaptor<op_match_proxy> ma
 
   if (!has_default) {
     auto message = VertexAdaptor<op_string>::create();
-    message->str_val = "UnhandledMatchError!";
+    message->str_val = "unhandled value in match!";
     auto emit_error = VertexAdaptor<op_func_call>::create(std::vector{message});
-    emit_error->set_string("warning");
+    emit_error->set_string("critical_error");
     const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{emit_error, case_break.clone()});
     switch_arms.emplace_back(VertexAdaptor<op_default>::create(case_body));
   }
diff --git a/tests/phpt/php8/match/015_strict_comparisons_jump_table.php b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
index 3206638307..bd6328ad7a 100644
--- a/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
+++ b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
@@ -5,26 +5,26 @@ function wrong() {
   return "wrong";
 }
 
-function test_int($char) {
-  return match ($char) {
-    0 => wrong(),
-    1 => wrong(),
-    2 => wrong(),
-    3 => wrong(),
-    4 => wrong(),
-    5 => wrong(),
-    6 => wrong(),
-    7 => wrong(),
-    8 => wrong(),
-    9 => wrong(),
-    default => 'Not matched',
-  };
-}
+// function test_int($char) {
+//   return match ($char) {
+//     0 => wrong(),
+//     1 => wrong(),
+//     2 => wrong(),
+//     3 => wrong(),
+//     4 => wrong(),
+//     5 => wrong(),
+//     6 => wrong(),
+//     7 => wrong(),
+//     8 => wrong(),
+//     9 => wrong(),
+//     default => 'Not matched',
+//   };
+// }
 
-foreach (range(0, 9) as $int) {
-  var_dump((string)$int);
-  var_dump(test_int((string)$int));
-}
+// foreach (range(0, 9) as $int) {
+//   var_dump((string)$int);
+//   var_dump(test_int((string)$int));
+// }
 
 function test_string($int) {
   return match ($int) {
diff --git a/tests/phpt/php8/match/020_bad_case.php b/tests/phpt/php8/match/020_bad_case.php
index 4e9e58ffa8..f41eeb4af8 100644
--- a/tests/phpt/php8/match/020_bad_case.php
+++ b/tests/phpt/php8/match/020_bad_case.php
@@ -1,5 +1,5 @@
 @kphp_should_fail php8
-/Expected expression before token '=>'/
+Expected expression before '=>'
 <?php
 
 match(10) {
diff --git a/tests/phpt/php8/match/021_several_default_arm.php b/tests/phpt/php8/match/021_several_default_arm.php
index a6f2898713..c6d5ec2142 100644
--- a/tests/phpt/php8/match/021_several_default_arm.php
+++ b/tests/phpt/php8/match/021_several_default_arm.php
@@ -1,5 +1,5 @@
 @kphp_should_fail php8
-/Match expressions may only contain one default arm/
+Match: several `default` cases found"
 <?php
 
 match(10) {
diff --git a/tests/phpt/php8/match/022_repeated_conditions.php b/tests/phpt/php8/match/022_repeated_conditions.php
index 7ddcf4c847..b9bd7c3300 100644
--- a/tests/phpt/php8/match/022_repeated_conditions.php
+++ b/tests/phpt/php8/match/022_repeated_conditions.php
@@ -1,5 +1,5 @@
 @kphp_should_fail php8
-/Repeated case \[10\] in switch\/match/
+Match: repeated cases found [10]
 <?php
 
 match(10) {
diff --git a/tests/phpt/php8/match/023_unhandeled_value.php b/tests/phpt/php8/match/023_unhandeled_value.php
index a16a939dec..5e9f199eed 100644
--- a/tests/phpt/php8/match/023_unhandeled_value.php
+++ b/tests/phpt/php8/match/023_unhandeled_value.php
@@ -1,5 +1,5 @@
 @kphp_runtime_should_warn php8
-/Unhandled match value '100'/
+Error: unhandled value in match!
 <?php
 
 match(100) {
diff --git a/tests/phpt/php8/match/024_unhandeled_array_value.php b/tests/phpt/php8/match/024_unhandeled_array_value.php
index 14c7509276..35c05d1a01 100644
--- a/tests/phpt/php8/match/024_unhandeled_array_value.php
+++ b/tests/phpt/php8/match/024_unhandeled_array_value.php
@@ -1,5 +1,4 @@
 @kphp_runtime_should_warn php8
-/Unhandled match value 'Array/
 <?php
 
 $options = [

From 35154d32896697f9e583e7105e05d28b14469d31 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Mon, 16 Jan 2023 18:33:23 +0300
Subject: [PATCH 4/8] Add new test; remove debug prints; add assertions

---
 compiler/gentree.cpp                          |  4 +-
 compiler/pipes/gen-tree-postprocess.cpp       | 13 ++-----
 .../015_strict_comparisons_jump_table.php     | 38 +++++++++----------
 .../match/{025_arrays.php => 020_arrays.php}  |  0
 tests/phpt/php8/match/021_double_match.php    | 18 +++++++++
 .../{020_bad_case.php => 101_bad_case.php}    |  0
 ...lt_arm.php => 102_several_default_arm.php} |  0
 ...itions.php => 103_repeated_conditions.php} |  0
 ...led_value.php => 104_unhandeled_value.php} |  0
 ...lue.php => 105_unhandeled_array_value.php} |  0
 10 files changed, 41 insertions(+), 32 deletions(-)
 rename tests/phpt/php8/match/{025_arrays.php => 020_arrays.php} (100%)
 create mode 100644 tests/phpt/php8/match/021_double_match.php
 rename tests/phpt/php8/match/{020_bad_case.php => 101_bad_case.php} (100%)
 rename tests/phpt/php8/match/{021_several_default_arm.php => 102_several_default_arm.php} (100%)
 rename tests/phpt/php8/match/{022_repeated_conditions.php => 103_repeated_conditions.php} (100%)
 rename tests/phpt/php8/match/{023_unhandeled_value.php => 104_unhandeled_value.php} (100%)
 rename tests/phpt/php8/match/{024_unhandeled_array_value.php => 105_unhandeled_array_value.php} (100%)

diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 15efdc26a5..0b6db36ea8 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -1251,9 +1251,7 @@ VertexAdaptor<op_match_proxy> GenTree::get_match() {
 
   CE(expect(tok_clbrc, "'}'"));
 
-  auto kek = VertexAdaptor<op_match_proxy>::create(match_condition, std::move(cases)).set_location(location);
-  kek.debugPrint();
-  return kek;
+  return VertexAdaptor<op_match_proxy>::create(match_condition, std::move(cases)).set_location(location);
 }
 
 VertexAdaptor<op_match_case> GenTree::get_match_case() {
diff --git a/compiler/pipes/gen-tree-postprocess.cpp b/compiler/pipes/gen-tree-postprocess.cpp
index fbba525914..3c7bf9c56b 100644
--- a/compiler/pipes/gen-tree-postprocess.cpp
+++ b/compiler/pipes/gen-tree-postprocess.cpp
@@ -4,6 +4,8 @@
 
 #include "compiler/pipes/gen-tree-postprocess.h"
 
+#include "auto/compiler/vertex/vertex-types.h"
+#include "common/algorithms/find.h"
 #include "compiler/compiler-core.h"
 #include "compiler/data/class-data.h"
 #include "compiler/data/lib-data.h"
@@ -234,10 +236,6 @@ VertexPtr GenTreePostprocessPass::on_enter_vertex(VertexPtr root) {
 }
 
 VertexPtr GenTreePostprocessPass::on_exit_vertex(VertexPtr root) {
-  if (current_function->name == "foo" && root->type() == op_function) {
-    root.debugPrint();
-  }
-  
   if (root->type() == op_var) {
     if (VertexUtil::is_superglobal(root->get_string())) {
       root->extra_type = op_ex_var_superglobal;
@@ -345,13 +343,10 @@ VertexPtr GenTreePostprocessPass::convert_match(VertexAdaptor<op_match_proxy> ma
   static const auto case_break = VertexAdaptor<op_break>::create(VertexUtil::create_int_const(1));
   
   for (const auto match_case : cases) {
-    // match_case.debugPrint();
     if (const auto ordinary_case = match_case.try_as<op_match_case>()) {
-      // puts("Have hew ordinary case!\n");
       const auto set_result = VertexAdaptor<op_set>::create(tmp_result_var, ordinary_case->result_expr());
       const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{set_result, case_break.clone()}).set_location(ordinary_case);
       for (const auto case_condition : ordinary_case->conditions()->args()) {
-        // puts("\tHave new condition!\n");
         switch_arms.emplace_back(VertexAdaptor<op_case>::create(case_condition, case_body));
       }
     }
@@ -361,9 +356,7 @@ VertexPtr GenTreePostprocessPass::convert_match(VertexAdaptor<op_match_proxy> ma
       const auto case_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{set_result, case_break.clone()}).set_location(default_case);
       switch_arms.emplace_back(VertexAdaptor<op_default>::create(case_body));
     }
-    else {
-      // TODO error
-    }
+    kphp_error(vk::any_of_equal(match_case->type(), op_match_case, op_match_default), "Internel error: invalid case type in match expression");
   }
 
   if (!has_default) {
diff --git a/tests/phpt/php8/match/015_strict_comparisons_jump_table.php b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
index bd6328ad7a..3206638307 100644
--- a/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
+++ b/tests/phpt/php8/match/015_strict_comparisons_jump_table.php
@@ -5,26 +5,26 @@ function wrong() {
   return "wrong";
 }
 
-// function test_int($char) {
-//   return match ($char) {
-//     0 => wrong(),
-//     1 => wrong(),
-//     2 => wrong(),
-//     3 => wrong(),
-//     4 => wrong(),
-//     5 => wrong(),
-//     6 => wrong(),
-//     7 => wrong(),
-//     8 => wrong(),
-//     9 => wrong(),
-//     default => 'Not matched',
-//   };
-// }
+function test_int($char) {
+  return match ($char) {
+    0 => wrong(),
+    1 => wrong(),
+    2 => wrong(),
+    3 => wrong(),
+    4 => wrong(),
+    5 => wrong(),
+    6 => wrong(),
+    7 => wrong(),
+    8 => wrong(),
+    9 => wrong(),
+    default => 'Not matched',
+  };
+}
 
-// foreach (range(0, 9) as $int) {
-//   var_dump((string)$int);
-//   var_dump(test_int((string)$int));
-// }
+foreach (range(0, 9) as $int) {
+  var_dump((string)$int);
+  var_dump(test_int((string)$int));
+}
 
 function test_string($int) {
   return match ($int) {
diff --git a/tests/phpt/php8/match/025_arrays.php b/tests/phpt/php8/match/020_arrays.php
similarity index 100%
rename from tests/phpt/php8/match/025_arrays.php
rename to tests/phpt/php8/match/020_arrays.php
diff --git a/tests/phpt/php8/match/021_double_match.php b/tests/phpt/php8/match/021_double_match.php
new file mode 100644
index 0000000000..a52df993a2
--- /dev/null
+++ b/tests/phpt/php8/match/021_double_match.php
@@ -0,0 +1,18 @@
+@ok php8
+<?php
+
+function f($int) {
+    return match (match ($int) {
+        1 => "one",
+        2 => "two",
+        default => "many",
+    }) {
+        "one " => 1,
+        "two" => 2,
+        default => 42,
+    };
+}
+
+echo f(1)  . "\n";
+echo f(2)  . "\n";
+echo f(42) . "\n";
diff --git a/tests/phpt/php8/match/020_bad_case.php b/tests/phpt/php8/match/101_bad_case.php
similarity index 100%
rename from tests/phpt/php8/match/020_bad_case.php
rename to tests/phpt/php8/match/101_bad_case.php
diff --git a/tests/phpt/php8/match/021_several_default_arm.php b/tests/phpt/php8/match/102_several_default_arm.php
similarity index 100%
rename from tests/phpt/php8/match/021_several_default_arm.php
rename to tests/phpt/php8/match/102_several_default_arm.php
diff --git a/tests/phpt/php8/match/022_repeated_conditions.php b/tests/phpt/php8/match/103_repeated_conditions.php
similarity index 100%
rename from tests/phpt/php8/match/022_repeated_conditions.php
rename to tests/phpt/php8/match/103_repeated_conditions.php
diff --git a/tests/phpt/php8/match/023_unhandeled_value.php b/tests/phpt/php8/match/104_unhandeled_value.php
similarity index 100%
rename from tests/phpt/php8/match/023_unhandeled_value.php
rename to tests/phpt/php8/match/104_unhandeled_value.php
diff --git a/tests/phpt/php8/match/024_unhandeled_array_value.php b/tests/phpt/php8/match/105_unhandeled_array_value.php
similarity index 100%
rename from tests/phpt/php8/match/024_unhandeled_array_value.php
rename to tests/phpt/php8/match/105_unhandeled_array_value.php

From cf27ababc077ac209eb21c3ac9f2bcc3077711d9 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Mon, 16 Jan 2023 18:41:28 +0300
Subject: [PATCH 5/8] Small fix

---
 compiler/gentree.cpp                    | 2 --
 compiler/pipes/collect-main-edges.cpp   | 2 +-
 compiler/pipes/gen-tree-postprocess.cpp | 1 -
 3 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 0b6db36ea8..4f51923345 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -1239,11 +1239,9 @@ VertexAdaptor<op_match_proxy> GenTree::get_match() {
     }
 
     if (cur->type() == tok_default) {
-      // printf("%s: new default arm!\n", __FUNCTION__);
       cases.emplace_back(get_match_default());
     }
     else {
-      // printf("%s: new ordinary arm!\n", __FUNCTION__);
       cases.emplace_back(get_match_case());
     }
     kphp_assert_msg(cases.back(), "Invalid 'match' case!");
diff --git a/compiler/pipes/collect-main-edges.cpp b/compiler/pipes/collect-main-edges.cpp
index a8ee0e485b..33e9291fe4 100644
--- a/compiler/pipes/collect-main-edges.cpp
+++ b/compiler/pipes/collect-main-edges.cpp
@@ -420,7 +420,7 @@ void CollectMainEdgesPass::on_switch(VertexAdaptor<op_switch> switch_op) {
       }
     }
   }
-  if (switch_op->kind == SwitchKind::IntSwitch) {
+  else if (switch_op->kind == SwitchKind::IntSwitch) {
     // in case of int-only switch, condition var is discarded, so there is
     // no real need in trying to insert an assignment node here
     create_type_assign(as_lvalue(switch_op->condition_on_switch()), TypeData::get_type(tp_int));
diff --git a/compiler/pipes/gen-tree-postprocess.cpp b/compiler/pipes/gen-tree-postprocess.cpp
index 3c7bf9c56b..bd5d0c4610 100644
--- a/compiler/pipes/gen-tree-postprocess.cpp
+++ b/compiler/pipes/gen-tree-postprocess.cpp
@@ -4,7 +4,6 @@
 
 #include "compiler/pipes/gen-tree-postprocess.h"
 
-#include "auto/compiler/vertex/vertex-types.h"
 #include "common/algorithms/find.h"
 #include "compiler/compiler-core.h"
 #include "compiler/data/class-data.h"

From 7dc074231fcf99d7f710c499b6ec5ddd4be79242 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Wed, 11 Jan 2023 07:16:32 +0300
Subject: [PATCH 6/8] Initial implementation of match

---
 compiler/pipes/gen-tree-postprocess.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/pipes/gen-tree-postprocess.cpp b/compiler/pipes/gen-tree-postprocess.cpp
index bd5d0c4610..118c0e36bb 100644
--- a/compiler/pipes/gen-tree-postprocess.cpp
+++ b/compiler/pipes/gen-tree-postprocess.cpp
@@ -235,6 +235,10 @@ VertexPtr GenTreePostprocessPass::on_enter_vertex(VertexPtr root) {
 }
 
 VertexPtr GenTreePostprocessPass::on_exit_vertex(VertexPtr root) {
+  if (current_function->name == "foo" && root->type() == op_function) {
+    root.debugPrint();
+  }
+  
   if (root->type() == op_var) {
     if (VertexUtil::is_superglobal(root->get_string())) {
       root->extra_type = op_ex_var_superglobal;

From 9c6f0895d25507626b22b68b605230d79bc4b02d Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Sat, 21 Jan 2023 17:58:49 +0300
Subject: [PATCH 7/8] Initial implementation

---
 compiler/debug.cpp                          |   1 +
 compiler/gentree.cpp                        | 218 ++++++++++++++++++++
 compiler/gentree.h                          |   2 +
 compiler/keywords.gperf                     |   1 +
 compiler/pipes/calc-real-defines-values.cpp |  13 ++
 compiler/pipes/inline-defines-usages.cpp    |  25 +++
 compiler/token.h                            |   1 +
 7 files changed, 261 insertions(+)

diff --git a/compiler/debug.cpp b/compiler/debug.cpp
index 91c469a800..23be98c1b9 100644
--- a/compiler/debug.cpp
+++ b/compiler/debug.cpp
@@ -65,6 +65,7 @@ std::string debugTokenName(TokenType t) {
     {tok_class, "tok_class"},
     {tok_interface, "tok_interface"},
     {tok_trait, "tok_trait"},
+    {tok_enum, "tok_enum"},
     {tok_extends, "tok_extends"},
     {tok_implements, "tok_implements"},
     {tok_namespace, "tok_namespace"},
diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 4f51923345..85d577e2b1 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -10,8 +10,11 @@
 #include "common/php-functions.h"
 #include "compiler/compiler-core.h"
 #include "compiler/data/class-data.h"
+#include "compiler/data/class-members.h"
 #include "compiler/data/define-data.h"
+#include "compiler/data/field-modifiers.h"
 #include "compiler/data/function-data.h"
+#include "compiler/data/function-modifiers.h"
 #include "compiler/data/lib-data.h"
 #include "compiler/data/src-file.h"
 #include "compiler/data/vertex-adaptor.h"
@@ -26,6 +29,9 @@
 #include "compiler/utils/string-utils.h"
 #include "compiler/vertex.h"
 #include "compiler/vertex-util.h"
+#include <algorithm>
+#include <cstddef>
+#include <iterator>
 
 #define CE(x) if (!(x)) {return {};}
 
@@ -1731,6 +1737,214 @@ VertexPtr GenTree::get_class(const PhpDocComment *phpdoc, ClassType class_type)
   return {};
 }
 
+VertexPtr GenTree::get_enum(const PhpDocComment *phpdoc) {
+  CE(cur->type() == tok_enum);
+  next_cur();
+
+  CE (!kphp_error(test_expect(tok_func_name), "Enum name expected"));
+
+  auto name_str = static_cast<std::string>(cur->str_val);
+  std::string full_class_name = processing_file->namespace_name.empty() ? std::string{name_str} : processing_file->namespace_name + "\\" + name_str;
+
+  kphp_error(processing_file->namespace_uses.find(name_str) == processing_file->namespace_uses.end(),
+             "Enum name is the same as one of 'use' at the top of the file");
+
+  const auto class_ptr = ClassPtr(new ClassData{ClassType::klass});
+  StackPushPop<ClassPtr> c_alive(class_stack, cur_class, class_ptr);
+  StackPushPop<FunctionPtr> f_alive(functions_stack, cur_function, cur_class->gen_holder_function(full_class_name));
+
+  cur_class->modifiers.set_final();
+  cur_class->file_id = processing_file;
+  cur_class->set_name_and_src_name(full_class_name); // with full namespaces and slashes
+  cur_class->phpdoc = phpdoc;
+  cur_class->is_immutable = true;
+  cur_class->location_line_num = line_num;
+
+  bool registered = G->register_class(cur_class);
+  if (registered) {
+    ++G->stats.total_classes;
+  }
+
+  cur_class->add_class_constant();
+  if (registered) {
+    G->register_and_require_function(cur_function, parsed_os, true);  // push the class down the pipeline
+  }
+
+  // generate body
+  next_cur();
+  CE(cur->type() == tok_opbrc);
+
+
+  VertexPtr body_vertex = get_statement();
+  kphp_assert_msg(body_vertex && body_vertex->type() == op_seq, "Incorrect enum body");
+  const auto body_seq = body_vertex.try_as<op_seq>();
+  std::vector<std::string> cases;
+
+  auto modifiers_field_private = FieldModifiers();
+  modifiers_field_private.set_private();
+
+  // generate 'public static self $EnumCase;'
+  for (const auto &stmt : body_seq->args()) {
+    if (const auto case_vertex = stmt.try_as<op_string>()) { // TODO replace op_string with smth else
+      const auto case_name = case_vertex->get_string();
+      cases.push_back(case_name);
+      auto var = VertexAdaptor<op_var>::create();
+      var->str_val = case_name;
+      cur_class->members.add_static_field(var, {}, modifiers_field_private, nullptr, cur_class->type_hint);
+    }
+    kphp_error(stmt->type() != op_var, "Fields are no allowed in enums");
+  }
+
+  bool has_unwanted_fields = false;
+  std::vector<Location> locations;
+
+  cur_class->members.for_each([&](const ClassMemberInstanceField & field){
+    if (field.local_name() != "name") { // TODO add "value" for backed
+      has_unwanted_fields = true;
+      locations.push_back(field.root->location);
+    }
+  });
+
+  if (has_unwanted_fields) {
+    for (const auto & location : locations) {
+      stage::set_line(location.get_line());
+      kphp_error(!has_unwanted_fields, "Fields are not allowed in enums");
+    }
+  }
+
+  // add $name field
+  auto modifiers_field_public = FieldModifiers();
+  modifiers_field_public.set_public();
+
+  auto name_vertex = VertexAdaptor<op_var>::create();
+  name_vertex->str_val = "name";
+  name_vertex->is_const = true;
+  cur_class->members.add_instance_field(name_vertex,
+                                        VertexAdaptor<op_string>::create(),
+                                        modifiers_field_public,
+                                        nullptr,
+                                        nullptr);
+
+  // add $cases_ and cases()
+  std::vector<VertexPtr> cases_internal;
+  std::transform(std::begin(cases),
+                std::end(cases),
+                std::back_inserter(cases_internal),
+                [&](const std::string & s) {
+                  auto resp = VertexAdaptor<op_string>::create();
+                  resp->str_val = s;
+                  return resp;
+                });
+  auto cases_vertex = VertexAdaptor<op_var>::create();
+  cases_vertex->str_val = "cases_";
+  auto cases_init_vertex = VertexAdaptor<op_array>::create(cases_internal);
+
+  cur_class->members.add_static_field(cases_vertex,
+                                      cases_init_vertex,
+                                      modifiers_field_private,
+                                      nullptr,
+                                      nullptr);
+
+  {
+    const auto params = VertexAdaptor<op_func_param_list>::create();
+    const auto body = VertexAdaptor<op_seq>::create(VertexAdaptor<op_return>::create(cases_init_vertex.clone()));
+    const auto cases_function = VertexAdaptor<op_function>::create(params, body);
+    const auto func_name = cur_class->name + "$$cases";
+    const auto func = FunctionData::create_function(func_name, cases_function, FunctionData::func_local);
+
+    auto f_alive = StackPushPop<FunctionPtr> (functions_stack, cur_function, func);
+
+    func->update_location_in_body();
+    func->is_inline = true;
+    func->modifiers = FunctionModifiers::nonmember();
+    func->modifiers.set_public();
+    func->phpdoc = phpdoc;
+    cur_class->members.add_static_method(func);
+    G->register_and_require_function(func, parsed_os, true);
+  }
+
+  CE (!kphp_error(body_vertex, "Failed to parse enum body"));
+
+  // create private constructor
+  {
+    auto param_var = VertexAdaptor<op_var>::create();
+    param_var->str_val = "name_";
+    const auto param = VertexAdaptor<op_func_param>::create(param_var.clone());
+
+    auto this_vertex = VertexAdaptor<op_var>::create();
+    this_vertex->str_val = "this";
+    auto inst_prop = VertexAdaptor<op_instance_prop>::create(this_vertex.clone());
+    inst_prop->str_val = "name";
+    const auto body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{
+      VertexAdaptor<op_set>::create(inst_prop, param_var.clone()),
+      VertexAdaptor<op_return>::create(this_vertex.clone())
+    });
+
+    auto func = VertexAdaptor<op_function>::create(VertexAdaptor<op_func_param_list>::create(std::vector<VertexPtr>{param}), body);
+
+    std::string func_name = replace_backslashes(cur_class->name) + "$$" + ClassData::NAME_OF_CONSTRUCT;
+    auto this_param = cur_class->gen_param_this(func->get_location());
+    func->param_list_ref() = VertexAdaptor<op_func_param_list>::create(this_param, func->param_list()->params());
+    VertexUtil::func_force_return(func, cur_class->gen_vertex_this(func->location));
+    auto ctor_function = FunctionData::create_function(func_name, func, FunctionData::func_local);
+
+    auto f_alive = StackPushPop<FunctionPtr> (functions_stack, cur_function, ctor_function);
+
+    ctor_function->update_location_in_body();
+    ctor_function->is_inline = true;
+    ctor_function->modifiers = FunctionModifiers::instance_private();
+    ctor_function->phpdoc = phpdoc;
+    cur_class->members.add_instance_method(ctor_function);
+    G->register_and_require_function(ctor_function, parsed_os, true);
+  }
+
+  // create getEnum* methods
+  for (const auto & case_name : cases) {
+    const auto params = VertexAdaptor<op_func_param_list>::create();
+
+    auto var = VertexAdaptor<op_var>::create();
+    var->str_val = cur_class->name + "$$" + case_name;
+
+    auto as_op_str = VertexAdaptor<op_string>::create();
+    as_op_str->str_val = case_name;
+
+    const auto cond = VertexAdaptor<op_conv_bool>::create(VertexAdaptor<op_eq3>::create(var.clone(), VertexAdaptor<op_null>::create()));
+    const auto ctor_call = gen_constructor_call_with_args(cur_class, std::vector<VertexPtr>{as_op_str}, auto_location());
+    const auto cond_body = VertexAdaptor<op_seq>::create(VertexAdaptor<op_set>::create(var.clone(), ctor_call));
+    const auto if_vertex = VertexAdaptor<op_if>::create(cond, cond_body);
+    const auto func_body = VertexAdaptor<op_seq>::create(std::vector<VertexPtr>{if_vertex, VertexAdaptor<op_return>::create(var.clone()), VertexAdaptor<op_return>::create()});
+    const auto func_vertex = VertexAdaptor<op_function>::create(params, func_body);
+    std::string func_name = replace_backslashes(cur_class->name) + "$$getEnum" + case_name;
+    auto function = FunctionData::create_function(func_name, func_vertex, FunctionData::func_local);
+
+    auto f_alive = StackPushPop<FunctionPtr> (functions_stack, cur_function, function);
+
+    function->update_location_in_body();
+    function->is_inline = true;
+    function->modifiers = FunctionModifiers::nonmember();
+    function->modifiers.set_public();
+    cur_class->members.add_static_method(function);
+    G->register_and_require_function(function, parsed_os, true);
+  }
+
+  return {};
+}
+
+VertexAdaptor<op_string> GenTree::get_enum_case() {
+
+  /*
+  enum {
+    ...
+    case ENUM_CASE;  <----- parse such a construction
+  }
+  */
+  CE(cur->type() == tok_case);
+  next_cur();
+  CE (!kphp_error(test_expect(tok_func_name), "Enum case name expected"));
+  auto response = VertexAdaptor<op_string>::create();
+  response->str_val = static_cast<std::string>(cur->str_val);
+  return response;
+}
 
 VertexAdaptor<op_func_call> GenTree::gen_constructor_call_with_args(const std::string &allocated_class_name, std::vector<VertexPtr> args, const Location &location) {
   auto alloc = VertexAdaptor<op_alloc>::create().set_location(location);
@@ -2008,6 +2222,8 @@ VertexPtr GenTree::get_statement(const PhpDocComment *phpdoc) {
       CE (check_seq_end());
       return res;
     }
+    case tok_case:
+      return get_enum_case();
     case tok_return:
       return get_return();
     case tok_continue:
@@ -2219,6 +2435,8 @@ VertexPtr GenTree::get_statement(const PhpDocComment *phpdoc) {
       kphp_error(processing_file->namespace_uses.empty(), "Usage of operator `use`(Aliasing/Importing) with traits is temporarily prohibited");
       return res;
     }
+    case tok_enum:
+      return get_enum(phpdoc);
     default: {
       auto res = get_expression();
       CE (check_statement_end());
diff --git a/compiler/gentree.h b/compiler/gentree.h
index e73f52baef..04dc472460 100644
--- a/compiler/gentree.h
+++ b/compiler/gentree.h
@@ -122,6 +122,8 @@ class GenTree {
   static VertexAdaptor<op_var> auto_capture_this_in_lambda(FunctionPtr f_lambda);
 
   VertexPtr get_class(const PhpDocComment *phpdoc, ClassType class_type);
+  VertexPtr get_enum(const PhpDocComment *phpdoc);
+  VertexAdaptor<op_string> get_enum_case();
   void parse_extends_implements();
 
   static VertexPtr process_arrow(VertexPtr lhs, VertexPtr rhs);
diff --git a/compiler/keywords.gperf b/compiler/keywords.gperf
index dcc6b98d0f..cb6ac43d19 100644
--- a/compiler/keywords.gperf
+++ b/compiler/keywords.gperf
@@ -32,6 +32,7 @@ match, tok_match
 class, tok_class
 interface, tok_interface
 trait, tok_trait
+enum, tok_enum
 const, tok_const
 default, tok_default
 do, tok_do
diff --git a/compiler/pipes/calc-real-defines-values.cpp b/compiler/pipes/calc-real-defines-values.cpp
index c4e0ca49ef..bef588ad68 100644
--- a/compiler/pipes/calc-real-defines-values.cpp
+++ b/compiler/pipes/calc-real-defines-values.cpp
@@ -94,6 +94,19 @@ void CalcRealDefinesAndAssignModulitesF::process_define_recursive(VertexPtr root
     if (define) {
       process_define(define);
     } else {
+      if (root->type() == op_func_name) {
+        // Check enums in a special way
+        // TODO replace with pure const later
+        const auto pos_double_dol = root->get_string().find("$$");
+        if (pos_double_dol != std::string::npos) {
+          std::string class_name = root->get_string().substr(0, pos_double_dol);
+          std::string enum_case_name = std::string(root->get_string().begin() + pos_double_dol + 2, root->get_string().end());
+          std::string need_method = class_name + "$$getEnum" + enum_case_name;
+          if (G->get_function(need_method)) {
+            return;
+          }
+        }
+      }
       kphp_error(0, fmt_format("Can't find definition for '{}'", define_name));
     }
   }
diff --git a/compiler/pipes/inline-defines-usages.cpp b/compiler/pipes/inline-defines-usages.cpp
index 530fe23cc9..0eef669547 100644
--- a/compiler/pipes/inline-defines-usages.cpp
+++ b/compiler/pipes/inline-defines-usages.cpp
@@ -5,10 +5,13 @@
 #include "compiler/pipes/inline-defines-usages.h"
 
 #include "compiler/data/class-data.h"
+#include "compiler/data/data_ptr.h"
 #include "compiler/data/define-data.h"
+#include "compiler/data/vertex-adaptor.h"
 #include "compiler/modulite-check-rules.h"
 #include "compiler/name-gen.h"
 #include "compiler/pipes/check-access-modifiers.h"
+#include "compiler/utils/string-utils.h"
 
 VertexPtr InlineDefinesUsagesPass::on_enter_vertex(VertexPtr root) {
   // defined('NAME') is replaced by true or false
@@ -34,6 +37,28 @@ VertexPtr InlineDefinesUsagesPass::on_enter_vertex(VertexPtr root) {
     std::string name = resolve_define_name(root->get_string());
     DefinePtr def = G->get_define(name);
     if (!def) {
+      std::string full_name = root->get_string();
+      const auto pos_colon = full_name.find("$$");
+      if (pos_colon != std::string::npos) {
+
+        full_name.replace(pos_colon, 2, "$$getEnum");
+        const auto class_name = std::string(full_name.begin(), full_name.begin() + pos_colon);
+
+
+        const auto klass = G->get_class(class_name);
+        kphp_assert_msg(klass, fmt_format("There is no enum-class with name '{}'", class_name));
+        const auto method_name = std::string(full_name.begin() + pos_colon + 2, full_name.end());
+
+        const auto * const method_data = klass->members.get_static_method(method_name);
+        kphp_assert_msg(method_data, fmt_format("There is no const nor enum case '{}'", replace_characters(std::string(root->get_string()), '$', ':')));
+        const auto method = method_data->function;
+
+        if (method) {
+          auto new_call = VertexAdaptor<op_func_call>::create(std::vector<VertexPtr>{}).set_location(root);
+          new_call->func_id = method;
+          return new_call;
+        }
+      }
       const auto readable_name = vk::replace_all(vk::replace_all(name, "$$", "::"), "$", "\\");
       kphp_error(0, fmt_format("Undefined constant '{}'", readable_name));
       return root;
diff --git a/compiler/token.h b/compiler/token.h
index 7251bec1fe..8d485d749e 100644
--- a/compiler/token.h
+++ b/compiler/token.h
@@ -48,6 +48,7 @@ enum TokenType {
   tok_class,
   tok_interface,
   tok_trait,
+  tok_enum,
   tok_extends,
   tok_implements,
   tok_namespace,

From e84971a6d32414569dfae02801cdd0606bf83b00 Mon Sep 17 00:00:00 2001
From: Mikhail Kornaukhov <mkornaukhov03@yandex.ru>
Date: Sun, 22 Jan 2023 01:35:28 +0300
Subject: [PATCH 8/8] Add tests

---
 compiler/gentree.cpp                          |  6 +++++
 tests/phpt/php8/enum/001_simple.php           | 10 +++++++
 tests/phpt/php8/enum/002_instance_method.php  | 14 ++++++++++
 tests/phpt/php8/enum/003_eq3_comparison.php   | 17 ++++++++++++
 tests/phpt/php8/enum/004_constant.php         | 15 +++++++++++
 tests/phpt/php8/enum/005_const_context.php    | 16 +++++++++++
 tests/phpt/php8/enum/006_func_param.php       | 17 ++++++++++++
 tests/phpt/php8/enum/007_instanceof.php       | 16 +++++++++++
 tests/phpt/php8/enum/008_with_match.php       | 27 +++++++++++++++++++
 tests/phpt/php8/enum/009_cases.php            | 19 +++++++++++++
 tests/phpt/php8/enum/101_case_in_class.php    |  7 +++++
 tests/phpt/php8/enum/102_redeclare_cases.php  | 13 +++++++++
 .../php8/enum/103_redeclare_construct.php     | 13 +++++++++
 tests/phpt/php8/enum/104_immutable_name.php   | 12 +++++++++
 tests/phpt/php8/enum/105_enum_is_final.php    |  7 +++++
 15 files changed, 209 insertions(+)
 create mode 100644 tests/phpt/php8/enum/001_simple.php
 create mode 100644 tests/phpt/php8/enum/002_instance_method.php
 create mode 100644 tests/phpt/php8/enum/003_eq3_comparison.php
 create mode 100644 tests/phpt/php8/enum/004_constant.php
 create mode 100644 tests/phpt/php8/enum/005_const_context.php
 create mode 100644 tests/phpt/php8/enum/006_func_param.php
 create mode 100644 tests/phpt/php8/enum/007_instanceof.php
 create mode 100644 tests/phpt/php8/enum/008_with_match.php
 create mode 100644 tests/phpt/php8/enum/009_cases.php
 create mode 100644 tests/phpt/php8/enum/101_case_in_class.php
 create mode 100644 tests/phpt/php8/enum/102_redeclare_cases.php
 create mode 100644 tests/phpt/php8/enum/103_redeclare_construct.php
 create mode 100644 tests/phpt/php8/enum/104_immutable_name.php
 create mode 100644 tests/phpt/php8/enum/105_enum_is_final.php

diff --git a/compiler/gentree.cpp b/compiler/gentree.cpp
index 85d577e2b1..40eea5faf3 100644
--- a/compiler/gentree.cpp
+++ b/compiler/gentree.cpp
@@ -1723,6 +1723,12 @@ VertexPtr GenTree::get_class(const PhpDocComment *phpdoc, ClassType class_type)
   VertexPtr body_vertex = get_statement();    // an empty op_seq
   CE (!kphp_error(body_vertex, "Failed to parse class body"));
 
+  if (const auto body_seq = body_vertex.try_as<op_seq>()) {
+    for (const auto & stmt : body_seq->args()) {
+      kphp_error_return(stmt->type() != op_string, "Case can only be used in enums") {};
+    }
+  }
+
   cur_class->add_class_constant(); // A::class
 
   if (auto constructor_method = cur_class->members.get_constructor()) {
diff --git a/tests/phpt/php8/enum/001_simple.php b/tests/phpt/php8/enum/001_simple.php
new file mode 100644
index 0000000000..eeb6f28c25
--- /dev/null
+++ b/tests/phpt/php8/enum/001_simple.php
@@ -0,0 +1,10 @@
+@ok php8
+<?php
+
+enum Status {
+    case Ok;
+    case Fail;
+}
+
+var_dump(Status::Ok->name);
+var_dump(Status::Fail->name);
diff --git a/tests/phpt/php8/enum/002_instance_method.php b/tests/phpt/php8/enum/002_instance_method.php
new file mode 100644
index 0000000000..481b685605
--- /dev/null
+++ b/tests/phpt/php8/enum/002_instance_method.php
@@ -0,0 +1,14 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+
+    public function dump() {
+        var_dump($this->name);
+    }
+}
+
+Foo::Bar->dump();
+Foo::Baz->dump();
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/003_eq3_comparison.php b/tests/phpt/php8/enum/003_eq3_comparison.php
new file mode 100644
index 0000000000..ed51f6d7b9
--- /dev/null
+++ b/tests/phpt/php8/enum/003_eq3_comparison.php
@@ -0,0 +1,17 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+
+    public function dump() {
+        var_dump($this->name);
+    }
+}
+
+var_dump(Foo::Bar === Foo::Baz);
+var_dump(Foo::Bar !== Foo::Baz);
+
+var_dump(Foo::Baz === Foo::Bar);
+var_dump(Foo::Baz !== Foo::Bar);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/004_constant.php b/tests/phpt/php8/enum/004_constant.php
new file mode 100644
index 0000000000..4655fe1144
--- /dev/null
+++ b/tests/phpt/php8/enum/004_constant.php
@@ -0,0 +1,15 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+    public function dump() {
+        var_dump($this->name);
+    }
+    const ONE = '1';
+}
+
+Foo::Bar->dump();
+Foo::Baz->dump();
+var_dump(Foo::ONE);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/005_const_context.php b/tests/phpt/php8/enum/005_const_context.php
new file mode 100644
index 0000000000..9f1e538f52
--- /dev/null
+++ b/tests/phpt/php8/enum/005_const_context.php
@@ -0,0 +1,16 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+    public function dump() {
+        var_dump($this->name);
+    }
+}
+
+const CONST_VAR = Foo::Bar;
+$var = Foo::Baz;
+
+CONST_VAR->dump();
+$var->dump();
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/006_func_param.php b/tests/phpt/php8/enum/006_func_param.php
new file mode 100644
index 0000000000..0515070f31
--- /dev/null
+++ b/tests/phpt/php8/enum/006_func_param.php
@@ -0,0 +1,17 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+    public function dump() {
+        var_dump($this->name);
+    }
+}
+
+function print_Foo(Foo $var) {
+    $var->dump();
+}
+
+print_Foo(Foo::Bar);
+print_Foo(Foo::Baz);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/007_instanceof.php b/tests/phpt/php8/enum/007_instanceof.php
new file mode 100644
index 0000000000..aaca95d306
--- /dev/null
+++ b/tests/phpt/php8/enum/007_instanceof.php
@@ -0,0 +1,16 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+}
+
+enum Baz {
+    case Qux;
+}
+
+var_dump(Foo::Bar instanceof Foo);
+var_dump(Baz::Qux instanceof Baz);
+
+var_dump(Foo::Bar instanceof Baz);
+var_dump(Baz::Qux instanceof Foo);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/008_with_match.php b/tests/phpt/php8/enum/008_with_match.php
new file mode 100644
index 0000000000..c16c4c97fc
--- /dev/null
+++ b/tests/phpt/php8/enum/008_with_match.php
@@ -0,0 +1,27 @@
+@ok php8
+
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+}
+
+$var = Foo::Bar;
+
+var_dump(
+    match ($var) {
+        Foo::Bar => "Bar",
+        Foo::Baz => "Baz",
+        default => "unreachable",
+    }
+);
+
+$var = Foo::Bar;
+var_dump(
+    match ($var) {
+        Foo::Bar => "Bar",
+        Foo::Baz => "Baz",
+        default => "unreachable",
+    }
+);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/009_cases.php b/tests/phpt/php8/enum/009_cases.php
new file mode 100644
index 0000000000..28a4fa1473
--- /dev/null
+++ b/tests/phpt/php8/enum/009_cases.php
@@ -0,0 +1,19 @@
+@ok php8
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+}
+
+enum Single {
+    case Single;
+}
+
+enum EmptyEnum {
+}
+
+
+var_dump(count(Foo::cases()));
+var_dump(count(Single::cases()));
+var_dump(count(EmptyEnum::cases()));
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/101_case_in_class.php b/tests/phpt/php8/enum/101_case_in_class.php
new file mode 100644
index 0000000000..ba1e1f9cd3
--- /dev/null
+++ b/tests/phpt/php8/enum/101_case_in_class.php
@@ -0,0 +1,7 @@
+@kphp_should_fail
+/Case can only be used in enums/
+<?php
+
+class Foo {
+    case Bar;
+}
diff --git a/tests/phpt/php8/enum/102_redeclare_cases.php b/tests/phpt/php8/enum/102_redeclare_cases.php
new file mode 100644
index 0000000000..0138314b78
--- /dev/null
+++ b/tests/phpt/php8/enum/102_redeclare_cases.php
@@ -0,0 +1,13 @@
+@kphp_should_fail
+/Redeclaration of function Foo::cases()/
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+    function cases() {
+        return 42;
+    }
+};
+
+var_dump(Foo::Bar->name);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/103_redeclare_construct.php b/tests/phpt/php8/enum/103_redeclare_construct.php
new file mode 100644
index 0000000000..3b25d2dd73
--- /dev/null
+++ b/tests/phpt/php8/enum/103_redeclare_construct.php
@@ -0,0 +1,13 @@
+@kphp_should_fail
+/Redeclaration of Foo::__construct()/
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+    function __construct() {
+        return $this;
+    }
+};
+
+var_dump(Foo::Bar->name);
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/104_immutable_name.php b/tests/phpt/php8/enum/104_immutable_name.php
new file mode 100644
index 0000000000..f330791907
--- /dev/null
+++ b/tests/phpt/php8/enum/104_immutable_name.php
@@ -0,0 +1,12 @@
+@kphp_should_fail
+/Modification of const variable: name/
+/Modification of const variable: name/
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+};
+
+Foo::Bar->name = "kek";
+Foo::Baz->name[0] = "s";
\ No newline at end of file
diff --git a/tests/phpt/php8/enum/105_enum_is_final.php b/tests/phpt/php8/enum/105_enum_is_final.php
new file mode 100644
index 0000000000..d066ae34c5
--- /dev/null
+++ b/tests/phpt/php8/enum/105_enum_is_final.php
@@ -0,0 +1,7 @@
+@kphp_should_fail
+/You cannot extends final class: Bar/
+<?php
+
+enum Foo {}
+
+class Bar extends Foo {}
\ No newline at end of file