fix(println): Enable printing of arrays/strings >2 in fmt strings (#2947

)

compiler/noirc_printable_type/src/lib.rs

@@ -131,12 +131,23 @@ fn convert_fmt_string_inputs(
     {
         let printable_type = fetch_printable_type(printable_value)?;
         let type_size = printable_type.field_count() as usize;
-
-        let mut input_values_as_fields = input_and_printable_values[i..(i + type_size)]
-            .iter()
-            .flat_map(|param| vecmap(param.values(), |value| value.to_field()));
-
-        let value = decode_value(&mut input_values_as_fields, &printable_type);
+        let value = match printable_type {
+            PrintableType::Array { .. } | PrintableType::String { .. } => {
+                // Arrays and strings are represented in a single value vector rather than multiple separate input values
+                let mut input_values_as_fields = input_and_printable_values[i]
+                    .values()
+                    .into_iter()
+                    .map(|value| value.to_field());
+                decode_value(&mut input_values_as_fields, &printable_type)
+            }
+            _ => {
+                // We must use a flat map here as each value in a struct will be in a separate input value
+                let mut input_values_as_fields = input_and_printable_values[i..(i + type_size)]
+                    .iter()
+                    .flat_map(|param| vecmap(param.values(), |value| value.to_field()));
+                decode_value(&mut input_values_as_fields, &printable_type)
+            }
+        };
 
         output.push((value, printable_type));
     }

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

@@ -39,6 +39,8 @@ fn main(x : Field, y : pub Field) {
 
     let struct_string = if x != 5 { f"{foo}" } else { f"{bar}" };
     std::println(struct_string);
+
+    regression_2906();
 }
 
 fn string_identity(string: fmtstr<14, (Field, Field)>) -> fmtstr<14, (Field, Field)> {
@@ -62,3 +64,19 @@ struct fooStruct {
     my_struct: myStruct,
     foo: Field,
 }
+
+fn regression_2906() {
+    let array_two_vals = [1, 2];
+    dep::std::println(f"array_two_vals: {array_two_vals}"); 
+
+    let label_two_vals = "12";
+    dep::std::println(f"label_two_vals: {label_two_vals}");
+
+    let array_five_vals = [1, 2, 3, 4, 5];
+    dep::std::println(f"array_five_vals: {array_five_vals}");
+
+    let label_five_vals = "12345";
+    dep::std::println(f"label_five_vals: {label_five_vals}");
+
+    dep::std::println(f"array_five_vals: {array_five_vals}, label_five_vals: {label_five_vals}");
+}