From a48258146dcca35b3b534493edbcc740bd6cfd03 Mon Sep 17 00:00:00 2001
From: Ryan Chandler <ryangjchandler@gmail.com>
Date: Tue, 13 Sep 2022 00:53:18 +0100
Subject: [PATCH] parser: support basic declare statements

---
 trunk_parser/src/ast.rs        |  9 +++++++
 trunk_parser/src/parser/mod.rs | 43 ++++++++++++++++++++++++++++++++--
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/trunk_parser/src/ast.rs b/trunk_parser/src/ast.rs
index 9a07530..4dd832e 100644
--- a/trunk_parser/src/ast.rs
+++ b/trunk_parser/src/ast.rs
@@ -300,9 +300,18 @@ pub enum Statement {
     Global {
         vars: Vec<Identifier>,
     },
+    Declare {
+        declares: Vec<DeclareItem>,
+    },
     Noop,
 }
 
+#[derive(Debug, Clone, PartialEq, Serialize)]
+pub struct DeclareItem {
+    pub key: Identifier,
+    pub value: Expression,
+}
+
 #[derive(Debug, Clone, Eq, PartialEq, Serialize)]
 pub enum CastKind {
     String,
diff --git a/trunk_parser/src/parser/mod.rs b/trunk_parser/src/parser/mod.rs
index 7e65477..6f8e122 100644
--- a/trunk_parser/src/parser/mod.rs
+++ b/trunk_parser/src/parser/mod.rs
@@ -1,7 +1,7 @@
 use crate::{
     ast::{
         Arg, ArrayItem, BackedEnumType, ClassFlag, ClosureUse, ElseIf, IncludeKind, MagicConst,
-        MethodFlag, StaticVar, Use, UseKind,
+        MethodFlag, StaticVar, Use, UseKind, DeclareItem,
     },
     Block, Case, Catch, Expression, Identifier, MatchArm, Program, Statement, Type,
 };
@@ -169,6 +169,31 @@ impl Parser {
         self.skip_comments();
 
         let statement = match &self.current.kind {
+            TokenKind::Declare => {
+                self.next();
+                self.lparen()?;
+
+                let mut declares = Vec::new();
+                while self.current.kind != TokenKind::RightParen {
+                    let key = self.ident()?;
+
+                    expect!(self, TokenKind::Equals, "expected =");
+
+                    let value = self.expression(0)?;
+
+                    self.optional_comma()?;
+
+                    declares.push(DeclareItem {
+                        key: key.into(),
+                        value,
+                    });
+                }
+
+                self.rparen()?;
+                self.semi()?;
+
+                Statement::Declare { declares }
+            },
             TokenKind::Global => {
                 self.next();
 
@@ -2151,7 +2176,7 @@ impl Display for ParseError {
 mod tests {
     use super::Parser;
     use crate::{
-        ast::{Arg, ArrayItem, ElseIf, IncludeKind, InfixOp, MethodFlag, PropertyFlag},
+        ast::{Arg, ArrayItem, ElseIf, IncludeKind, InfixOp, MethodFlag, PropertyFlag, DeclareItem},
         Catch, Expression, Identifier, Param, Statement, Type,
     };
     use trunk_lexer::Lexer;
@@ -3338,6 +3363,20 @@ mod tests {
         );
     }
 
+    #[test]
+    fn basic_declare() {
+        assert_ast("<?php declare(A='B');", &[
+            Statement::Declare {
+                declares: vec![
+                    DeclareItem {
+                        key: "A".into(),
+                        value: Expression::ConstantString { value: "B".into() }
+                    }
+                ]
+            }
+        ]);
+    }
+
     fn assert_ast(source: &str, expected: &[Statement]) {
         let mut lexer = Lexer::new(None);
         let tokens = lexer.tokenize(source).unwrap();