From 9ab82059a14deba8021390840ca81176a7e67944 Mon Sep 17 00:00:00 2001
From: Ryan Chandler <ryangjchandler@gmail.com>
Date: Tue, 9 Aug 2022 00:00:14 +0100
Subject: [PATCH] parser: support `throw` expressions

It's worth noting that a `throw` will always be an expression in the Trunk parser.
PHP-Parser will convert standalone `throw` expressions into a dedicated `throw`
statement for backwards-compatibility reasons.
---
 trunk_lexer/src/lexer.rs       | 1 +
 trunk_lexer/src/token.rs       | 2 ++
 trunk_parser/src/ast.rs        | 3 +++
 trunk_parser/src/parser/mod.rs | 7 +++++++
 4 files changed, 13 insertions(+)

diff --git a/trunk_lexer/src/lexer.rs b/trunk_lexer/src/lexer.rs
index b475652..9340adb 100644
--- a/trunk_lexer/src/lexer.rs
+++ b/trunk_lexer/src/lexer.rs
@@ -749,6 +749,7 @@ fn identifier_to_keyword(ident: &str) -> Option<TokenKind> {
         "return" => TokenKind::Return,
         "static" => TokenKind::Static,
         "switch" => TokenKind::Switch,
+        "throw" => TokenKind::Throw,
         "trait" => TokenKind::Trait,
         "true" | "TRUE" => TokenKind::True,
         "try" => TokenKind::Try,
diff --git a/trunk_lexer/src/token.rs b/trunk_lexer/src/token.rs
index d7b5f1c..ce01b83 100644
--- a/trunk_lexer/src/token.rs
+++ b/trunk_lexer/src/token.rs
@@ -125,6 +125,7 @@ pub enum TokenKind {
     Slash,
     Static,
     Switch,
+    Throw,
     Trait,
     TripleEquals,
     True,
@@ -261,6 +262,7 @@ impl Display for TokenKind {
             Self::Slash => "/",
             Self::Static => "static",
             Self::Switch => "switch",
+            Self::Throw => "throw",
             Self::Trait => "trait",
             Self::TripleEquals => "===",
             Self::True => "true",
diff --git a/trunk_parser/src/ast.rs b/trunk_parser/src/ast.rs
index 9292bc3..e2d2150 100644
--- a/trunk_parser/src/ast.rs
+++ b/trunk_parser/src/ast.rs
@@ -394,6 +394,9 @@ pub enum Expression {
         condition: Box<Self>,
         arms: Vec<MatchArm>,
     },
+    Throw {
+        value: Box<Expression>,
+    },
 }
 
 #[derive(Debug, PartialEq, Clone, Serialize)]
diff --git a/trunk_parser/src/parser/mod.rs b/trunk_parser/src/parser/mod.rs
index 765e745..357ed15 100644
--- a/trunk_parser/src/parser/mod.rs
+++ b/trunk_parser/src/parser/mod.rs
@@ -959,6 +959,13 @@ impl Parser {
         self.skip_comments();
 
         let mut lhs = match &self.current.kind {
+            TokenKind::Throw => {
+                self.next();
+
+                let value = self.expression(0)?;
+
+                Expression::Throw { value: Box::new(value) }
+            },
             TokenKind::Clone => {
                 self.next();