lsmem: String path concat on Windows

src/uu/lsmem/src/lsmem.rs

@@ -360,12 +360,9 @@ impl Options {
 }
 
 fn read_info(lsmem: &mut Lsmem, opts: &mut Options) {
+    let path_block_size = Path::new(&opts.sysmem).join(PATH_SUB_BLOCK_SIZE_BYTES);
     lsmem.block_size = u64::from_str_radix(
-        &read_file_content::<String>(Path::new(&format!(
-            "{}/{}",
-            opts.sysmem, PATH_SUB_BLOCK_SIZE_BYTES
-        )))
-        .unwrap(),
+        &read_file_content::<String>(path_block_size.as_path()).unwrap(),
         16,
     )
     .unwrap();

tests/by-util/test_lsmem.rs

@@ -7,7 +7,13 @@ use crate::common::util::TestScenario;
 
 #[must_use]
 fn sysroot() -> String {
-    format!("{}/tests/fixtures/lsmem/input", env!("CARGO_MANIFEST_DIR"))
+    path_concat!(
+        env!("CARGO_MANIFEST_DIR"),
+        "tests",
+        "fixtures",
+        "lsmem",
+        "input"
+    )
 }
 
 fn sysroot_test_with_args(expected_output: &str, args: &[&str]) {