Fix formatter discarding nul bytes.

CHANGELOG.md

@@ -16,6 +16,7 @@
 - **aikup**: error message when version is not found. @rvcas
 - **aiken**: support outputting mainnet addresses for validators. @rvcas
 - **aiken-lang**: added serde to CheckedModule to encode modules as cbor. @rvcas
+- **aiken-lang**: Strings can contain a nul byte using the escape sequence `\0`. @KtorZ
 
 ### Fixed
 
@@ -32,7 +33,7 @@
 - **aiken-lang**: disallow `MLResult` in a type definition. @rvcas
 - **aiken-lang**: reversed deserialization of bls types out of data types. @rvcas
 - **aiken-lang**: validator args unexpectedly unbound causing code gen crashes. @rvcas
-- **aiken-lang**: allow implicitly discarded values when right-hand-side unified with `Void`. @KtorZ
+- **aiken-lang**: allow implicitly discarded values when right-hand side unified with `Void`. @KtorZ
 
 ### Changed
 

crates/aiken-lang/src/format.rs

@@ -2138,6 +2138,7 @@ fn escape(string: &str) -> String {
             '\n' => vec!['\\', 'n'],
             '\r' => vec!['\\', 'r'],
             '\t' => vec!['\\', 't'],
+            '\0' => vec!['\\', '0'],
             '"' => vec!['\\', c],
             '\\' => vec!['\\', c],
             _ => vec![c],

crates/aiken-lang/src/tests/format.rs

@@ -20,6 +20,18 @@ fn format_simple_module() {
     );
 }
 
+#[test]
+fn format_nul_byte() {
+    assert_format!(
+        r#"
+        fn label(str: String) -> Void {
+          str
+            |> builtin.append_string(@"\0", _)
+            |> builtin.debug(Void)
+        }"#
+    );
+}
+
 #[test]
 fn format_g1_element_constant() {
     assert_format!(

crates/aiken-lang/src/tests/snapshots/format_nul_byte.snap

@@ -0,0 +1,9 @@
+---
+source: crates/aiken-lang/src/tests/format.rs
+description: "Code:\n\nfn label(str: String) -> Void {\n  str\n    |> builtin.append_string(@\"\\0\", _)\n    |> builtin.debug(Void)\n}"
+---
+fn label(str: String) -> Void {
+  str
+    |> builtin.append_string(@"\0", _)
+    |> builtin.debug(Void)
+}