From dddc9db805bce87ddd0f68749640228ffe703921 Mon Sep 17 00:00:00 2001
From: guwirth <guenter.wirth@etas.com>
Date: Thu, 29 Aug 2024 16:53:23 +0200
Subject: [PATCH] C++23 extend init-statement to allow alias-declaration -
 Extend init-statement (of for loop) to allow alias-declaration
 [P2360R0](https://wg21.link/P2360R0) - linked #2536

---
 cxx-squid/dox/diff-cpp20-cpp23_grammar.txt                 | 5 -----
 .../src/main/java/org/sonar/cxx/parser/CxxGrammarImpl.java | 3 ++-
 .../src/test/java/org/sonar/cxx/parser/StatementTest.java  | 7 +++++--
 .../src/test/resources/parser/own/C++23/init-statement.cc  | 4 ++++
 4 files changed, 11 insertions(+), 8 deletions(-)
 create mode 100644 cxx-squid/src/test/resources/parser/own/C++23/init-statement.cc

diff --git a/cxx-squid/dox/diff-cpp20-cpp23_grammar.txt b/cxx-squid/dox/diff-cpp20-cpp23_grammar.txt
index ae20df630..a5ae8a2fa 100644
--- a/cxx-squid/dox/diff-cpp20-cpp23_grammar.txt
+++ b/cxx-squid/dox/diff-cpp20-cpp23_grammar.txt
@@ -184,11 +184,6 @@ postfix-expression:
 
 **A.6 Statements [gram.stmt]**
 
-init-statement:
-   expression-statement
-   simple-declaration
-   alias-declaration
-
 label:
    attribute-specifier-seqopt identifier :
    attribute-specifier-seqopt case constant-expression :
diff --git a/cxx-squid/src/main/java/org/sonar/cxx/parser/CxxGrammarImpl.java b/cxx-squid/src/main/java/org/sonar/cxx/parser/CxxGrammarImpl.java
index 6ba2fc746..b84c6f397 100644
--- a/cxx-squid/src/main/java/org/sonar/cxx/parser/CxxGrammarImpl.java
+++ b/cxx-squid/src/main/java/org/sonar/cxx/parser/CxxGrammarImpl.java
@@ -928,7 +928,8 @@ private static void statements(LexerfulGrammarBuilder b) {
     b.rule(initStatement).is(
       b.firstOf(
         expressionStatement, // C++
-        simpleDeclaration // C++
+        simpleDeclaration, // C++
+        aliasDeclaration // C++23
       )
     );
 
diff --git a/cxx-squid/src/test/java/org/sonar/cxx/parser/StatementTest.java b/cxx-squid/src/test/java/org/sonar/cxx/parser/StatementTest.java
index a4194c825..326c34f27 100644
--- a/cxx-squid/src/test/java/org/sonar/cxx/parser/StatementTest.java
+++ b/cxx-squid/src/test/java/org/sonar/cxx/parser/StatementTest.java
@@ -251,7 +251,9 @@ void iterationStatement_reallife() {
       // CLI extension
       .matches("for each(String^% s in arr) { s = i++.ToString(); }")
       // C++17 structered bindings
-      .matches("for (const auto&[key, val] : mymap) { std::cout << key << \": \" << val << std::endl; }");
+      .matches("for (const auto&[key, val] : mymap) { std::cout << key << \": \" << val << std::endl; }")
+      // C++23
+      .matches("for (using T = int; T e : v) ;");
   }
 
   @Test
@@ -259,7 +261,8 @@ void forInitStatement_reallife() {
     setRootRule(CxxGrammarImpl.initStatement);
 
     assertThatParser()
-      .matches("int i=1;");
+      .matches("int i=1;")
+      .matches("using T = int;"); // C++23
   }
 
   @Test
diff --git a/cxx-squid/src/test/resources/parser/own/C++23/init-statement.cc b/cxx-squid/src/test/resources/parser/own/C++23/init-statement.cc
new file mode 100644
index 000000000..1c6511fc0
--- /dev/null
+++ b/cxx-squid/src/test/resources/parser/own/C++23/init-statement.cc
@@ -0,0 +1,4 @@
+void sample() {
+   for (using T = int; T e : v)
+      /* something */;
+}