From 884c8e515ffce07952e196ec6fd5dab51342d120 Mon Sep 17 00:00:00 2001
From: Greg Shuflin <greg.shuflin@protonmail.com>
Date: Sun, 21 Nov 2021 01:54:34 -0800
Subject: [PATCH] Fix string literal escape parsing

---
 schala-lang/src/parsing/peg_parser.rs | 19 +++++++++----------
 schala-lang/src/parsing/test.rs       |  3 +--
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/schala-lang/src/parsing/peg_parser.rs b/schala-lang/src/parsing/peg_parser.rs
index af8ea73..f845ba7 100644
--- a/schala-lang/src/parsing/peg_parser.rs
+++ b/schala-lang/src/parsing/peg_parser.rs
@@ -423,7 +423,7 @@ peg::parser! {
         rule pattern_literal() -> Pattern =
             "true" { Pattern::Literal(PatternLiteral::BoolPattern(true)) } /
             "false" { Pattern::Literal(PatternLiteral::BoolPattern(false)) } /
-            s:bare_string_literal() { Pattern::Literal(PatternLiteral::StringPattern(Rc::new(s.to_string()))) } /
+            s:bare_string_literal() { Pattern::Literal(PatternLiteral::StringPattern(Rc::new(s))) } /
             sign:("-"?)  num:(float_literal() / nat_literal()) {
                 let neg = sign.is_some();
                 Pattern::Literal(PatternLiteral::NumPattern { neg, num })
@@ -447,19 +447,18 @@ peg::parser! {
             }
 
         rule string_literal() -> ExpressionKind =
-            prefix:identifier()? s:bare_string_literal(){ ExpressionKind::StringLiteral{ s: Rc::new(s.to_string()),
+            prefix:identifier()? s:bare_string_literal(){ ExpressionKind::StringLiteral{ s: Rc::new(s),
                 prefix: prefix.map(rc_string)
             } }
 
-        rule bare_string_literal() -> &'input str =
-            "\"" s:$(string_component()*) "\"" { s }
+        rule bare_string_literal() -> String =
+            "\"" chars:string_component()* "\"" { chars.into_iter().collect::<String>() }
 
-        rule string_component() -> &'input str =
-            r#"\\"# { "\\" } /
-            r#"\""# { "\"" } /
-            r#"\t"# { "\t" } /
-            r#"\n"# { "\n" } /
-            ch:$([^ '"' ]) { ch }
+        rule string_component() -> char =
+            !(r#"""# / r#"\"#) ch:$([_]) { ch.chars().next().unwrap() } /
+            r#"\u{"# value:$(['0'..='9' | 'a'..='f' | 'A'..='F']+) "}" { char::from_u32(u32::from_str_radix(value, 16).unwrap()).unwrap() } /
+            r#"\n"# { '\n' } / r#"\t"# { '\t' } / r#"\""# { '"' } / r#"\\"# { '\\' } /
+      expected!("Valid escape sequence")
 
         rule bool_literal() -> ExpressionKind =
             "true" { ExpressionKind::BoolLiteral(true) } / "false" { ExpressionKind::BoolLiteral(false) }
diff --git a/schala-lang/src/parsing/test.rs b/schala-lang/src/parsing/test.rs
index 95fae54..17591fb 100644
--- a/schala-lang/src/parsing/test.rs
+++ b/schala-lang/src/parsing/test.rs
@@ -189,8 +189,7 @@ fn string_literals() {
         r#"b"some bytestring""#,
         expr(StringLiteral { s: rc("some bytestring"), prefix: Some(rc("b")) })
     );
-    //NOTE I'm not 100% sure this case is correct, but I'll deal with it later
-    //assert_expr!(r#""Do \n \" escapes work\t""#, expr(StringLiteral(rc("Do \n \" escapes work\t"))));
+    assert_expr!(r#""Do \n \" escapes work\t""#, expr(strlit("Do \n \" escapes work\t")));
 }
 
 #[test]