Are /* and ../* ignore options useful?

[winksaville]

What do ignore "/" and "../" do?

xtaskops/xtaskops/src/tasks.rs

Lines 69 to 72 in 51f458f

	"--ignore",
	"../*",
	"--ignore",
	"/*",

I believe they do nothing in grcov and are superfluous.

Here's how I arrive at that conclusion

I've added some debug logging to grcov and investigated how globset works and AFAICT --ignore "/*" would would ignore files that have an absolute path that begins with a / and --ignore "../*" would ignore any explicitly relative paths that begin with ../.

After looking at the original code in fn rewrite_paths:

    if let Some(p) = &source_dir {
        assert!(p.is_absolute());
    }


    // Traverse source dir and store all paths, reversed.
    let mut file_to_paths: FxHashMap<String, Vec<PathBuf>> = FxHashMap::default();
    if let Some(ref source_dir) = source_dir {
        for entry in WalkDir::new(&source_dir)
            .into_iter()
            .filter_entry(|e| !is_hidden(e) && !is_symbolic_link(e))
        {
            let entry = entry
                .unwrap_or_else(|_| panic!("Failed to open directory '{}'.", source_dir.display()));


            let full_path = entry.path();
            if !full_path.is_file() {
                continue;
            }


            let path = full_path.strip_prefix(&source_dir).unwrap().to_path_buf();
            if to_ignore_globset.is_match(&path) {
                continue;
            }


            let name = entry.file_name().to_str().unwrap().to_string();
            match file_to_paths.entry(name) {
                hash_map::Entry::Occupied(f) => f.into_mut().push(path),
                hash_map::Entry::Vacant(v) => {
                    v.insert(vec![path]);
                }
            };
        }
    }

I added some debug logging to print the full_path and path:

            println!("checking full_path: {:?}", full_path);
            let path = full_path.strip_prefix(&source_dir).unwrap().to_path_buf();
            println!("checking  stripped: {:?}", path);
            if to_ignore_globset.is_match(&path) {
                println!("ignoring     path: {:?}", path);
                continue;
            }

And here is some output where `--ignore "xtask/*" is processed:

checking full_path: "/home/wink/prgs/rust/myrepos/workspace-template-with-xtask/xtask/Cargo.lock"
checking  stripped: "xtask/Cargo.lock"
ignoring     path: "xtask/Cargo.lock"
checking full_path: "/home/wink/prgs/rust/myrepos/workspace-template-with-xtask/xtask/Cargo.toml"
checking  stripped: "xtask/Cargo.toml"
ignoring     path: "xtask/Cargo.toml"
checking full_path: "/home/wink/prgs/rust/myrepos/workspace-template-with-xtask/xtask/src/main.rs"
checking  stripped: "xtask/src/main.rs"
ignoring     path: "xtask/src/main.rs"

As can be seen, full_path always begins with / and path never begins with / or ../ but instead is always
relative to source_dir. To me, that means that "/" and "../" will never match path and are therefore superfluous.

[jondot]

@winksaville I'm stunned that I missed this comment!
Sorry for that, looks like you did quite a research
I'd be happy to accept a PR that fixes this
Again -- apologies for missing it