diff --git a/vlib/v/fmt/fm_new_int_test.v b/vlib/v/fmt/fm_new_int_test.v
new file mode 100644
index 0000000000..ae11a91b8f
--- /dev/null
+++ b/vlib/v/fmt/fm_new_int_test.v
@@ -0,0 +1,69 @@
+// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+import os
+import term
+import benchmark
+import v.ast
+import v.fmt
+import v.parser
+import v.pref
+import v.util.diff
+import v.util.vtest
+
+const vroot = @VEXEROOT
+const tdir = os.join_path(vroot, 'vlib', 'v', 'fmt')
+const fpref = &pref.Preferences{
+	is_fmt: true
+}
+
+fn run_fmt(mut input_files []string) {
+	fmt_message := 'vfmt new_int tests'
+	eprintln(term.header(fmt_message, '-'))
+	tmpfolder := os.temp_dir()
+	assert input_files.len > 0
+	input_files = vtest.filter_vtest_only(input_files)
+	if input_files.len == 0 {
+		// No need to produce a failing test here.
+		eprintln('no tests found with VTEST_ONLY filter set to: ' + os.getenv('VTEST_ONLY'))
+		exit(0)
+	}
+	mut fmt_bench := benchmark.new_benchmark()
+	fmt_bench.set_total_expected_steps(input_files.len)
+	for istep, ipath in input_files {
+		fmt_bench.cstep = istep
+		fmt_bench.step()
+		opath := ipath.replace('_input.vv', '_expected_new_int.vv')
+		if !os.exists(opath) {
+			// skip not exist files
+			continue
+		}
+		expected_ocontent := os.read_file(opath) or {
+			fmt_bench.fail()
+			eprintln(fmt_bench.step_message_fail('cannot read from ${opath}'))
+			continue
+		}
+		mut table := ast.new_table()
+		file_ast := parser.parse_file(ipath, mut table, .parse_comments, fpref)
+		result_ocontent := fmt.fmt(file_ast, mut table, fpref, false, new_int: true)
+		if expected_ocontent != result_ocontent {
+			fmt_bench.fail()
+			eprintln(fmt_bench.step_message_fail('file ${ipath} after formatting, does not look as expected.'))
+			vfmt_result_file := os.join_path(tmpfolder, 'vfmt_run_over_${os.file_name(ipath)}')
+			os.write_file(vfmt_result_file, result_ocontent) or { panic(err) }
+			println(diff.compare_files(opath, vfmt_result_file) or { err.msg() })
+			continue
+		}
+		fmt_bench.ok()
+		eprintln(fmt_bench.step_message_ok(ipath))
+	}
+	fmt_bench.stop()
+	eprintln(term.h_divider('-'))
+	eprintln(fmt_bench.total_message(fmt_message))
+	assert fmt_bench.nfail == 0
+}
+
+fn test_new_int_fmt() {
+	mut input_files := os.walk_ext(os.join_path(tdir, 'tests'), '_input.vv')
+	run_fmt(mut input_files)
+}
diff --git a/vlib/v/fmt/tests/functions_expected_new_int.vv b/vlib/v/fmt/tests/functions_expected_new_int.vv
new file mode 100644
index 0000000000..4b18b2d8d8
--- /dev/null
+++ b/vlib/v/fmt/tests/functions_expected_new_int.vv
@@ -0,0 +1,68 @@
+fn C.func(arg i32) i32
+
+fn fn_variadic(arg int, args ...string) {
+	println('Do nothing')
+}
+
+fn fn_with_assign_stmts() {
+	_, _ := fn_with_multi_return()
+}
+
+fn fn_with_multi_return() (int, string) {
+	return 0, 'test'
+}
+
+fn voidfn() {
+	println('this is a function that does not return anything')
+}
+
+fn fn_with_1_arg(arg int) int {
+	return 0
+}
+
+fn fn_with_2a_args(arg1 int, arg2 int) int {
+	return 0
+}
+
+fn fn_with_2_args_to_be_shorten(arg1 int, arg2 int) int {
+	return 0
+}
+
+fn fn_with_2b_args(arg1 string, arg2 int) int {
+	return 0
+}
+
+fn fn_with_3_args(arg1 string, arg2 int, arg3 User) int {
+	return 0
+}
+
+fn (this User) fn_with_receiver() {
+	println('')
+}
+
+fn fn_with_option() ?int {
+	if true {
+		return error('true')
+	}
+	return 30
+}
+
+fn (f Foo) fn_with_option() ?int {
+	if true {
+		return error('true')
+	}
+	return 40
+}
+
+fn mut_array(mut a []int) {
+	println(1)
+}
+
+fn fn_with_ref_return() &Foo {
+	return &Foo{}
+}
+
+@[inline]
+fn fn_with_flag() {
+	println('flag')
+}
diff --git a/vlib/v/fmt/tests/new_int_expected_new_int.vv b/vlib/v/fmt/tests/new_int_expected_new_int.vv
new file mode 100644
index 0000000000..1c1a5e1b0d
--- /dev/null
+++ b/vlib/v/fmt/tests/new_int_expected_new_int.vv
@@ -0,0 +1,5 @@
+module main
+
+fn C.abc(a i32, b i32, c charptr) i32
+
+fn abc(a int, b int, c charptr) int
diff --git a/vlib/v/fmt/tests/new_int_input.vv b/vlib/v/fmt/tests/new_int_input.vv
new file mode 100644
index 0000000000..e1e8b9eaa9
--- /dev/null
+++ b/vlib/v/fmt/tests/new_int_input.vv
@@ -0,0 +1,6 @@
+module main
+
+fn C.abc(a int, b int, c charptr) int
+
+fn abc(a int, b int, c charptr) int
+
diff --git a/vlib/v/fmt/tests/translated_module_expected.vv b/vlib/v/fmt/tests/translated_module_expected.vv
new file mode 100644
index 0000000000..c62c810f87
--- /dev/null
+++ b/vlib/v/fmt/tests/translated_module_expected.vv
@@ -0,0 +1,9 @@
+@[translated]
+module aa
+
+fn C.abc(a int, b int)
+
+fn abc(x int, y int) {
+	s := int(123)
+	dump(s)
+}
diff --git a/vlib/v/fmt/tests/translated_module_expected_new_int.vv b/vlib/v/fmt/tests/translated_module_expected_new_int.vv
new file mode 100644
index 0000000000..6b10e92dae
--- /dev/null
+++ b/vlib/v/fmt/tests/translated_module_expected_new_int.vv
@@ -0,0 +1,9 @@
+@[translated]
+module aa
+
+fn C.abc(a i32, b i32)
+
+fn abc(x i32, y i32) {
+	s := i32(123)
+	dump(s)
+}
diff --git a/vlib/v/fmt/tests/translated_module_input.vv b/vlib/v/fmt/tests/translated_module_input.vv
new file mode 100644
index 0000000000..3df31f8b20
--- /dev/null
+++ b/vlib/v/fmt/tests/translated_module_input.vv
@@ -0,0 +1,10 @@
+@[translated]
+module aa
+
+fn C.abc(a int, b int)
+
+fn abc(x int, y int) {
+        s := int(123)
+        dump(s)
+}
+