allow newlines and trailing commas in function declarations

ast/src/leo.pest

@@ -191,7 +191,7 @@ type_circuit = { identifier }
 // Declared in types/array_type.rs
 type_array = { type_data ~ ("[" ~ number_positive ~ "]")+ }
 
-type_tuple = { "(" ~ type_ ~ ("," ~ type_)+ ~ ")" }
+type_tuple = { "(" ~ NEWLINE* ~ type_ ~ ("," ~ NEWLINE* ~ type_)+ ~ ","? ~ NEWLINE* ~ ")" }
 
 /// Values
 
@@ -381,7 +381,7 @@ input = {
     function_input
     | input_keyword
 }
-input_tuple = _{ "(" ~(input ~ ("," ~ NEWLINE* ~ input)*)? ~ ")"}
+input_tuple = _{ "(" ~ NEWLINE* ~ (input ~ ("," ~ NEWLINE* ~ input)* ~ ","?)? ~ NEWLINE* ~ ")"}
 
 
 /// Imports

compiler/tests/function/input/newlines.in

@@ -0,0 +1,7 @@
+[main]
+a: u32 = 0;
+b: u32 = 0;
+
+[registers]
+a: u32 = 0;
+b: u32 = 0;

compiler/tests/function/mod.rs

@@ -41,6 +41,20 @@ fn test_iteration_repeated() {
     assert_satisfied(program);
 }
 
+#[test]
+fn test_newlines() {
+    let input_bytes = include_bytes!("input/newlines.in");
+    let program_bytes = include_bytes!("newlines.leo");
+    let program = parse_program_with_input(program_bytes, input_bytes).unwrap();
+
+    let expected_bytes = include_bytes!("output_/newlines.out");
+    let expected = std::str::from_utf8(expected_bytes).unwrap();
+    let actual_bytes = get_output(program);
+    let actual = std::str::from_utf8(actual_bytes.bytes().as_slice()).unwrap();
+
+    assert_eq!(expected, actual);
+}
+
 #[test]
 fn test_multiple_returns() {
     let bytes = include_bytes!("multiple.leo");

compiler/tests/function/newlines.leo

@@ -0,0 +1,9 @@
+function main(
+    a: u32,
+    b: u32,
+) -> (
+    u32,
+    u32,
+) {
+    return (a, b)
+}

compiler/tests/function/output_/newlines.out

@@ -0,0 +1,3 @@
+[registers]
+a: u32 = 0u32;
+b: u32 = 0u32;