fix: don't let nargo fmt produce multiple trailing newlines (#7444)

noir_stdlib/src/ecdsa_secp256k1.nr

@@ -19,4 +19,3 @@ pub fn verify_signature_slice(
 ) -> bool
 // docs:end:ecdsa_secp256k1_slice
 {}
-

noir_stdlib/src/meta/op.nr

@@ -222,4 +222,3 @@ impl BinaryOp {
         }
     }
 }
-

noir_stdlib/src/ops/arith.nr

@@ -321,4 +321,3 @@ impl Neg for i64 {
     }
 }
 // docs:end:neg-trait-impls
-

noir_stdlib/src/ops/bit.nr

@@ -341,4 +341,3 @@ impl Shr for i64 {
         self >> other
     }
 }
-

test_programs/compile_success_empty/brillig_integer_binary_operations/src/main.nr

@@ -77,4 +77,3 @@ unconstrained fn shr(x: u32, y: u8) -> u32 {
 unconstrained fn shl(x: u32, y: u8) -> u32 {
     x << y
 }
-

test_programs/compile_success_empty/comptime_as_field/src/main.nr

@@ -3,4 +3,3 @@ fn main() {
         let _: U128 = U128::from_integer(1);
     }
 }
-

test_programs/compile_success_empty/comptime_fmt_strings/src/main.nr

@@ -26,4 +26,3 @@ fn hello_world() {}
 comptime fn call(x: Quoted) -> Quoted {
     quote { $x() }
 }
-

test_programs/compile_success_empty/comptime_from_field/src/main.nr

@@ -3,4 +3,3 @@ fn main() {
         let _: Field = U128::from_hex("0x0").to_integer();
     }
 }
-

test_programs/compile_success_empty/comptime_traits/src/main.nr

@@ -31,4 +31,3 @@ pub fn neg_at_comptime() {
         let _result = -value;
     }
 }
-

test_programs/compile_success_empty/conditional_regression_to_bits/src/main.nr

@@ -23,4 +23,3 @@ fn main() {
     }
     assert(c1 == 1);
 }
-

test_programs/compile_success_empty/eq_derivation_with_numeric_generics/src/main.nr

@@ -9,4 +9,3 @@ fn main() {
     let bar = Foo { a: [0; 10], b: 28 };
     assert(foo != bar);
 }
-

test_programs/compile_success_empty/trait_override_implementation/src/main.nr

@@ -80,4 +80,3 @@ fn main(x: Field) {
     assert(bar_mut.f4() == 4, "14");
     assert(bar_mut.f5() == 50, "15");
 }
-

test_programs/compile_success_empty/unquote_trait_constraint_in_trait_impl_position/src/main.nr

@@ -21,4 +21,3 @@ comptime fn foo(_: FunctionDefinition) -> Quoted {
         }
     }
 }
-

test_programs/execution_success/bit_and/src/main.nr

@@ -13,4 +13,3 @@ fn main(x: Field, y: Field, a: Field, b: Field) {
     let b_as_u8 = b as u8;
     assert((a_as_u8 & b_as_u8) == a_as_u8);
 }
-

test_programs/execution_success/bool_not/src/main.nr

@@ -1,4 +1,3 @@
 fn main(x: u1) {
     assert(!x == 0);
 }
-

test_programs/execution_success/bool_or/src/main.nr

@@ -3,4 +3,3 @@ fn main(x: u1, y: u1) {
 
     assert(x | y | x == 1);
 }
-

test_programs/execution_success/brillig_calls_conditionals/src/main.nr

@@ -36,4 +36,3 @@ unconstrained fn entry_point(x: u32) -> u32 {
 
     result
 }
-

test_programs/execution_success/brillig_nested_arrays/src/main.nr

@@ -41,4 +41,3 @@ fn main(x: Field, y: Field) {
         create_and_assert_inside_brillig(x, y);
     }
 }
-

test_programs/execution_success/brillig_pedersen/src/main.nr

@@ -24,4 +24,3 @@ unconstrained fn main(
     let hash = std::hash::pedersen_commitment_with_separator([state], 0);
     assert(std::hash::pedersen_commitment_with_separator([43], 0).x == hash.x);
 }
-

test_programs/execution_success/cast_bool/src/main.nr

@@ -3,4 +3,3 @@ fn main(x: Field, y: Field) {
     let t = z as u8;
     assert(t == 1);
 }
-

test_programs/execution_success/conditional_regression_661/src/main.nr

@@ -25,4 +25,3 @@ fn issue_661_bar(a: [u32; 4]) -> [u32; 4] {
     b[0] = a[0] + 1;
     b
 }
-

test_programs/execution_success/databus/src/main.nr

@@ -9,4 +9,3 @@ fn main(mut x: u32, y: call_data(0) u32, z: call_data(0) [u32; 4]) -> return_dat
 unconstrained fn foo(x: u32) -> u32 {
     x + 1
 }
-

test_programs/execution_success/fold_complex_outputs/src/main.nr

@@ -69,4 +69,3 @@ fn map_fields(mut input: ParentStruct) -> ParentStruct {
 
     input
 }
-

test_programs/execution_success/global_var_entry_point_used_in_another_entry/src/main.nr

@@ -41,4 +41,3 @@ unconstrained fn entry_point_one_diff_global(x: Field, y: Field) {
     let z = THREE + x + y;
     assert(z == 4);
 }
-

test_programs/execution_success/if_else_chain/src/main.nr

@@ -12,4 +12,3 @@ fn main(a: u32, mut c: [u32; 4]) {
         assert(c[0] == 10);
     }
 }
-

test_programs/execution_success/nested_array_dynamic/src/main.nr

@@ -73,4 +73,3 @@ fn main(mut x: [Foo; 4], y: pub Field) {
     foo_parents[y - 2].foos[y - 3].b = foo_parents[y - 2].foos[y - 2].b;
     assert(foo_parents[1].foos[0].b == [20, 19, 5000]);
 }
-

test_programs/execution_success/nested_arrays_from_brillig/src/main.nr

@@ -24,4 +24,3 @@ fn main(values: [Field; 6]) {
     let notes = unsafe { create_inside_brillig(values) };
     assert(access_nested(notes) == (2 + 4 + 3 + 1));
 }
-

test_programs/execution_success/pedersen_check/src/main.nr

@@ -17,4 +17,3 @@ fn main(x: Field, y: Field, salt: Field, out_x: Field, out_y: Field, out_hash: F
     let hash = std::hash::pedersen_commitment([state]);
     assert(std::hash::pedersen_commitment([43]).x == hash.x);
 }
-

test_programs/execution_success/pedersen_commitment/src/main.nr

@@ -5,4 +5,3 @@ fn main(x: Field, y: Field, expected_commitment: std::embedded_curve_ops::Embedd
     assert_eq(commitment.y, expected_commitment.y);
 }
 // docs:end:pedersen-commitment
-

test_programs/execution_success/pedersen_hash/src/main.nr

@@ -4,4 +4,3 @@ fn main(x: Field, y: Field, expected_hash: Field) {
     assert_eq(hash, expected_hash);
 }
 // docs:end:pedersen-hash
-

test_programs/execution_success/reference_only_used_as_alias/src/main.nr

@@ -90,4 +90,3 @@ fn main(input: [Field; 4], randomness: Field, context_input: u32) {
     let event0 = ExampleEvent0 { value0: input[0], value1: input[1] };
     event0.emit(encode_event_with_randomness(&mut context, randomness));
 }
-

test_programs/execution_success/slice_dynamic_index/src/main.nr

@@ -305,4 +305,3 @@ fn dynamic_slice_merge_push_then_pop(mut slice: [Field], x: Field, y: Field) {
     let (_, elem) = slice.pop_back();
     assert(elem == y);
 }
-

test_programs/execution_success/slice_regex/src/main.nr

@@ -805,4 +805,3 @@ fn main() {
 //     assert_eq(result.leftover.len, 0);
 //     // adapted URL parser: (https?:\/\/)?([\da-c.\-]+)\.([a-c.]+)([\/\w \.\-]*)*\/?
 // }
-

test_programs/execution_success/struct_fields_ordering/src/main.nr

@@ -9,4 +9,3 @@ fn main(y: pub myStruct) {
     assert(y.foo == 5);
     assert(y.bar == 7);
 }
-

test_programs/execution_success/submodules/src/main.nr

@@ -12,4 +12,3 @@ mod my_submodule {
 
     pub fn my_helper() {}
 }
-

test_programs/execution_success/u128/src/main.nr

@@ -39,4 +39,3 @@ fn main(mut x: u32, y: u32, z: u32, big_int: U128, hexa: str<7>) {
     assert(shift << 127 == U128::from_integer(0));
     assert(U128::from_integer(3).to_integer() == 3);
 }
-

test_programs/execution_success/wrapping_operations/src/main.nr

@@ -3,4 +3,3 @@ fn main(x: u8, y: u8) {
     assert(std::wrapping_add(y, 1) == x);
     assert(std::wrapping_mul(y, y) == 1);
 }
-

test_programs/noir_test_success/bounded_vec/src/main.nr

@@ -269,4 +269,3 @@ fn test_vec_any_not_default() {
     vec.extend_from_array([2, 4]);
     assert(!vec.any(|v| v == default_value));
 }
-

test_programs/noir_test_success/brillig_overflow_checks/src/main.nr

@@ -20,4 +20,3 @@ unconstrained fn test_overflow_mul() {
     let b: u8 = 2;
     assert_eq(a * b, 0);
 }
-

test_programs/noir_test_success/mock_oracle/src/main.nr

@@ -151,4 +151,3 @@ fn test_mock_struct_field() {
         assert_eq(20, struct_field(point, another_array));
     }
 }
-

tooling/nargo_fmt/src/formatter.rs

@@ -107,6 +107,7 @@ impl<'a> Formatter<'a> {
         );
 
         self.format_parsed_module(parsed_module, self.ignore_next);
+        self.buffer.trim_multiple_newlines();
     }
 
     pub(crate) fn format_parsed_module(&mut self, parsed_module: ParsedModule, ignore_next: bool) {

tooling/nargo_fmt/src/formatter/buffer.rs

@@ -56,6 +56,13 @@ impl Buffer {
         }
     }
 
+    /// Trim multiple newlines from the end of the buffer, keeping at most one.
+    pub(crate) fn trim_multiple_newlines(&mut self) {
+        while self.buffer.ends_with("\n\n") {
+            self.buffer.truncate(self.buffer.len() - 1);
+        }
+    }
+
     pub(crate) fn contents(self) -> String {
         self.buffer
     }

tooling/nargo_fmt/src/formatter/comments_and_whitespace.rs

@@ -858,4 +858,11 @@ global x = 1;
 ";
         assert_format(src, expected);
     }
+
+    #[test]
+    fn trims_newlines_from_the_end_of_the_file() {
+        let src = "global x: Field = 1;\n\n\n";
+        let expected = "global x: Field = 1;\n";
+        assert_format(src, expected);
+    }
 }

tooling/nargo_fmt/src/formatter/function.rs

@@ -542,7 +542,6 @@ fn bar() {
 // noir-fmt:ignore
 fn baz() { let  z  = 3  ; 
             }
-
 ";
         assert_format(src, expected);
     }

tooling/nargo_fmt/tests/expected/databus.nr

@@ -1,2 +1 @@
 fn main(x: pub u8, y: call_data(0) u8) -> return_data u32 {}
-

tooling/nargo_fmt/tests/expected/fn.nr

@@ -95,4 +95,3 @@ fn four() {}
 
 #[test(should_fail_with = "oops")]
 fn five() {}
-

tooling/nargo_fmt/tests/expected/ignore.nr

@@ -24,4 +24,3 @@ fn mk_array() {
                 ];
     let array = [1];
 }
-

tooling/nargo_fmt/tests/expected/trait.nr

@@ -1,2 +1 @@
 trait Foo: Bar + Baz {}
-

tooling/nargo_fmt/tests/expected/trait_alias.nr

@@ -83,4 +83,3 @@ fn main() {
 
     assert(0.foo_3().bar_3() == baz_3(0));
 }
-

tooling/nargo_fmt/tests/expected/unsafe.nr

@@ -12,4 +12,3 @@ fn main(x: pub u8, y: u8) {
         assert_eq(x, y);
     }
 }
-