GHC 2017-03-22

2017-03-22 05:05:52, https://git.io/vyhIx in Homebrew/brew

> Does git log let us improve performance by setting a maxdepth on the search in a non-shallow clone?

Sure, you can use a commit range. That's rather arbitrary though.

2017-03-22 04:41:48, https://git.io/vyhUk in Homebrew/brew

missing_formula: warn when git-log takes very long
==================================================

- [x] Have you followed the guidelines in our [Contributing](https://github.com/Homebrew/brew/blob/master/CONTRIBUTING.md) document?
- [x] Have you checked to ensure there aren't other open [Pull Requests](https://github.com/Homebrew/brew/pulls) for the same change?
- [x] Have you added an explanation of what your changes do and why you'd like us to include them?
- [ ] Have you written new tests for your changes? [Here's an example](https://github.com/Homebrew/homebrew/pull/49031).
- [ ] Have you successfully run `brew tests` with your changes locally?

-----

Since #1732, trying to install or info a nonexistent formula that's neither blacklisted nor recorded in a tap migration database triggers a search through the entire git history, which could take very long (~10s on my machine) in a non-shallow core tap:

```zsh
$ time (brew info foo)  # nothing happens for ten seconds
Error: No available formula with the name "foo"
( brew info foo; )  8.97s user 0.65s system 96% cpu 9.990 total
```

This is confusing to users (users shouldn't encounter the output of `deleted_reason` until we drop homebrew/boneyard). Therefore, we should let users know what's going on behind the scenes if `git-log` goes on for too long. I'm setting the threshold to two seconds. After this PR:

```zsh
$ time (brew info foo)
Warning: Searching through git history. This may take a while...
Error: No available formula with the name "foo"
( brew info foo; )  9.01s user 0.66s system 98% cpu 9.859 total
```

An iTerm2 screenshot with timestamps on each output line:

<img width="958" alt="screen shot 2017-03-22 at 12 40 16 am" src="https://cloud.githubusercontent.com/assets/4149852/24182430/36831f60-0e98-11e7-8655-d664b186e3fe.png">

2017-03-22 02:22:40, https://git.io/vyphk in Homebrew/homebrew-core

I can reproduce the issue. The project's distribution channel seems to be in serious trouble though: hosted on Google Code, downloading from Google Drive... Wow...

Code appears to be hosted at https://github.com/bcoudurier/FFmbc now. README says stable version is 0.7.3, Changelog.FFmbc disagrees and says 0.7.5. Nevertheless, I can find neither a 0.7.3 tag (other than the old FFmpeg 0.7.3 tag) nor a download link anywhere. Is there a home page somewhere? No idea. Maybe commits updating the changelog should be treated as tags? Again, no idea.

You can try to compile from the master branch of https://github.com/bcoudurier/FFmbc. Seriously though, I'd recommend using FFmpeg instead if you can.