Show headers only when multiple files are passed

[solson]

Sorry if this has already been asked, but I couldn't find it.

Could it be made possible to configure bat to show headers (--style=header) only when more than one file is passed? I like to keep my --style quite minimal, and when viewing a single file, the filename is usually just extra noise to me, but with multiple files it's practically a necessity. Thanks!

[sharkdp]

Thank you for the feedback.

Originally, I had some plans to add more meta information to the header (like the detected syntax, the Git status of the file, …).

If we are going to leave this at the file name only, I agree that it's not very useful for a single file. It would only make sense for consistency.

[sharkdp]

We've decided in #1395 that we don't want to add a new command line option for this. There might be another way (by specifying a new --style switch), but I'm inclined to close this as "won't do".

[solson]

I wouldn't mind this much if I could define a shell alias that passes --style=numbers for the single-file case and --style=header,numbers for the multi-file case, but the problem is I'd have to effectively reimplement bat's flag parsing to count the number of inputs, or else accept being inaccurate in some cases. Even just ignoring arguments starting with - for the count would be relatively messy.

Can you think of any other way to support this cleanly?

[solson]

I suppose I could be happy enough with two separate aliases, one doing bat --style=header,numbers and the other doing bat --style=numbers, but then I have to mention my "default" style in multiple places. A single alias would be ideal, though, so I can never forget and have to rerun with the other alias.

[sharkdp]

Okay, let's try to implement this. We need to discuss the design, but maybe something like this could work:

• Add a new single-file-header style component
• Change the meaning of header to mean: only show headers if there are multiple files
• Set the default style to header,single-file-header,….

Note: I haven't completely thought this through. Let's please discuss all implications of this before implementing it.

[lilyball]

I really want this. I feel like the best solution here is not to add new style components, but instead to just add a new flag --single-file-style=… that lets me override the style for single files, and if not specified it will use the --style config.

The question here is whether BAT_STYLE would affect this flag if it's not at the default. If BAT_STYLE is specified for a single invocation of bat then it should, if it's just set generally in the environment then it probably shouldn't, and I'm not sure which is more common.

Or maybe we can be a little more subtle and do a --multi-file-style= flag instead, with a new style component inherit that means "inherit the --style. With this approach the default is just --multi-file-style=inherit. And the reason for switching to multi-file instead of single-file is so we can then write e.g. --multi-file-style=inherit,header to add the header to the existing style. And with this approach BAT_STYLE will obviously just affect --style.

I do think conceptually a --single-file-style makes a bit more sense than a --multi-file-style, but since the common use-case here is "show a header for multiple files", the --single-file-style approach is harder to use.