feat(formatter): add formatter support for array literals (#3061)

Co-authored-by: kevaundray <kevtheappdev@gmail.com>

tooling/nargo_cli/tests/execution_success/brillig_unitialised_arrays/src/main.nr

@@ -9,5 +9,5 @@ fn sum_x(notes: [Field; 2], x: Field, y: Field) -> Field {
 }
 
 unconstrained fn create_notes(x: Field, y: Field) -> [Field; 2] {
-    [x,y]
-}
+    [x, y]
+}

tooling/nargo_cli/tests/execution_success/conditional_regression_661/src/main.nr

@@ -18,7 +18,7 @@ fn test5(a : u32) {
 
 
 fn issue_661_foo(array: [u32;4], b:u32) ->[u32;1] {
-    [array[0]+b]
+    [array[0] + b]
 }
 
 fn issue_661_bar(a : [u32;4]) ->[u32;4] {

tooling/nargo_cli/tests/execution_success/distinct_keyword/src/main.nr

@@ -1,4 +1,4 @@
 // Example that uses the distinct keyword
 fn main(x: pub Field) -> distinct pub [Field;2] {
-    [x+1, x]
+    [x + 1, x]
 }

tooling/nargo_fmt/src/visitor/expr.rs

@@ -1,5 +1,6 @@
 use noirc_frontend::{
-    hir::resolution::errors::Span, BlockExpression, Expression, ExpressionKind, Statement,
+    hir::resolution::errors::Span, ArrayLiteral, BlockExpression, Expression, ExpressionKind,
+    Literal, Statement,
 };
 
 use super::FmtVisitor;
@@ -38,6 +39,22 @@ impl FmtVisitor<'_> {
                     self.format_expr(infix.rhs)
                 )
             }
+            ExpressionKind::Literal(literal) => match literal {
+                Literal::Integer(_) => slice!(self, span.start(), span.end()).to_string(),
+                Literal::Array(ArrayLiteral::Repeated { repeated_element, length }) => {
+                    format!("[{}; {length}]", self.format_expr(*repeated_element))
+                }
+                // TODO: Handle line breaks when array gets too long.
+                Literal::Array(ArrayLiteral::Standard(exprs)) => {
+                    let contents: Vec<String> =
+                        exprs.into_iter().map(|expr| self.format_expr(expr)).collect();
+                    format!("[{}]", contents.join(", "))
+                }
+
+                Literal::Bool(_) | Literal::Str(_) | Literal::FmtStr(_) | Literal::Unit => {
+                    literal.to_string()
+                }
+            },
             // TODO:
             _expr => slice!(self, span.start(), span.end()).to_string(),
         }

tooling/nargo_fmt/tests/expected/literals.nr

@@ -0,0 +1,13 @@
+fn main() {
+    [1, 2, 3, 4, 5];
+
+    [1; 5];
+
+    [0xff; 5];
+
+    true;
+
+    "hello world";
+
+    ()
+}

tooling/nargo_fmt/tests/input/literals.nr

@@ -0,0 +1,15 @@
+
+fn main() {
+    [1,2,3,4,5];
+
+
+    [1;5];
+
+    [0xff;5];
+
+    true;
+
+    "hello world";
+
+    ()
+}