From 6d83ec2079a400adb2c810f732810a8133a88819 Mon Sep 17 00:00:00 2001
From: Andrew Morris <voltrevo@gmail.com>
Date: Fri, 1 Mar 2024 12:19:12 +1100
Subject: [PATCH] Fix get_span_text unicode bug

---
 valuescript_compiler/src/expression_compiler.rs | 13 +------------
 valuescript_compiler/src/get_span_text.rs       | 13 +++++++++++++
 valuescript_compiler/src/lib.rs                 |  1 +
 valuescript_compiler/src/src_hash.rs            | 13 ++-----------
 4 files changed, 17 insertions(+), 23 deletions(-)
 create mode 100644 valuescript_compiler/src/get_span_text.rs

diff --git a/valuescript_compiler/src/expression_compiler.rs b/valuescript_compiler/src/expression_compiler.rs
index 12b2d02..35461a7 100644
--- a/valuescript_compiler/src/expression_compiler.rs
+++ b/valuescript_compiler/src/expression_compiler.rs
@@ -6,6 +6,7 @@ use swc_common::Spanned;
 use crate::asm::{Array, Instruction, Label, Number, Object, Register, Structured, Value};
 use crate::diagnostic::{Diagnostic, DiagnosticContainer, DiagnosticReporter};
 use crate::function_compiler::{FunctionCompiler, Functionish};
+use crate::get_span_text::get_span_text;
 use crate::ident::Ident as CrateIdent;
 use crate::scope::{NameId, OwnerId};
 use crate::scope_analysis::{fn_to_owner_id, NameType};
@@ -1882,15 +1883,3 @@ pub fn value_from_literal(lit: &swc_ecma_ast::Lit) -> Result<Value, &'static str
     JSXText(_) => return Err("JSXText literals"),
   })
 }
-
-fn get_span_text(span: swc_common::Span, source: &str) -> String {
-  let swc_common::BytePos(start) = span.lo;
-  let swc_common::BytePos(end) = span.hi;
-
-  let chars = source
-    .chars()
-    .skip(start as usize)
-    .take((end - start) as usize);
-
-  chars.collect::<String>()
-}
diff --git a/valuescript_compiler/src/get_span_text.rs b/valuescript_compiler/src/get_span_text.rs
new file mode 100644
index 0000000..b9edad7
--- /dev/null
+++ b/valuescript_compiler/src/get_span_text.rs
@@ -0,0 +1,13 @@
+use valuescript_vm::unicode_at;
+
+pub fn get_span_text(span: swc_common::Span, source: &str) -> String {
+  let mut res = String::new();
+
+  for i in span.lo().0..span.hi().0 {
+    if let Some(c) = unicode_at(source.as_bytes(), source.len(), i as usize) {
+      res.push(c);
+    }
+  }
+
+  res
+}
diff --git a/valuescript_compiler/src/lib.rs b/valuescript_compiler/src/lib.rs
index 3b56811..b69edee 100644
--- a/valuescript_compiler/src/lib.rs
+++ b/valuescript_compiler/src/lib.rs
@@ -7,6 +7,7 @@ mod diagnostic;
 mod expression_compiler;
 mod function_compiler;
 mod gather_modules;
+mod get_span_text;
 mod ident;
 mod import_pattern;
 mod inline_valuescript;
diff --git a/valuescript_compiler/src/src_hash.rs b/valuescript_compiler/src/src_hash.rs
index 12a7a74..235dce7 100644
--- a/valuescript_compiler/src/src_hash.rs
+++ b/valuescript_compiler/src/src_hash.rs
@@ -1,19 +1,10 @@
-use swc_common::BytePos;
 use tiny_keccak::{Hasher, Keccak};
 
-use crate::asm::Hash;
+use crate::{asm::Hash, get_span_text::get_span_text};
 
 pub fn src_hash(source: &str, span: swc_common::Span) -> Hash {
-  let BytePos(start) = span.lo;
-  let BytePos(end) = span.hi;
-
-  let chars = source
-    .chars()
-    .skip(start as usize)
-    .take((end - start) as usize);
-
   let mut k = Keccak::v256();
-  k.update(chars.collect::<String>().as_bytes());
+  k.update(get_span_text(span, source).as_bytes());
 
   let mut output = [0u8; 32];
   k.finalize(&mut output);