Wrong mime-type guessed for some files

[Aetf]

I noticed that handlr incorrectly guesses some of the Qt Designer UI files' mime type, it should be application/x-designer, but handlr thinks it is application/x-gtk-builder.

$ handlr open SettingsWidgetFdoSecrets.ui
no handlers found for 'application/x-gtk-builder'

Directly using xdg-mime from xdg-utils returns the correct result:

$ xdg-mime query filetype SettingsWidgetFdoSecrets.ui
application/x-designer

From the code I see that the file name based guess is always preferred over a content-based guess.

However, according to the xdg_mime doc, the correct behavior is to first do a name-based guess, if the result has multiple matches, do a content-based guess and use the latter as the final result.

I tried a simple PoC and xdg_mime indeed returns the correct result in content guess.

use xdg_mime::SharedMimeInfo;
use std::path::PathBuf;

fn main() {
    let path = PathBuf::from("SettingsWidgetFdoSecrets.ui");
    let db = SharedMimeInfo::new();
    let name_guesses = db.get_mime_types_from_file_name(&path.file_name().unwrap().to_string_lossy());
    println!("name guesses: {:?}", name_guesses);
    let content_guess = db.guess_mime_type().path(&path).guess();
    println!("content guess: {:?}, uncertain {}", content_guess.mime_type(), content_guess.uncertain());
}

prints

name guesses: ["application/x-designer", "application/x-gtk-builder"]
content guess: "application/x-designer", uncertain false

The file used in the above examples: SettingsWidgetFdoSecrets.ui.zip