> any thoughts on how to handle the case where someone passes --with-imagemagick@6 but doesn't pass --with-cocoa, since that seems to result in no imagemagick support?
I personally don't use an IM-capable Emacs (actually I use Emacs in a tty 99.9% of the time), but AFIAK IM support in Emacs is only useful for displaying images. Without `--with-cocoa` (or the historical `--with-x11`), Emacs is only going to work in ttys; what's the point of IM support in that case?
By the way, in response to
> I'd like to hear what the imagemagick 7 plan is before we start adding versioned dependencies in perpetuity.
There's a patch or two floating around on the mailing list without much interest, justifiably so because the whole world isn't moving to IMv7 (just look at any popular server distro).
Even if a patch is accepted tomorrow, it won't make it into Emacs 25.2 (which is already on rc2), and given Emacs's release cycle, it will be many months before IMv7 is supported in a stable.
audit: do not warn about reachability of `brew mirror`ed URL
============================================================
- [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?
-----
A `brew mirror`ed URL is usually not yet reachable at the time of pull request.
Example of a false positive fixed by this PR: https://github.com/Homebrew/homebrew-core/pull/10587.
---
**Update.** `dev-cmd/pull.rb` has been updated to warn about unreachable Bintray mirror URLs, and prompt maintainers to run `brew mirror` in that case.
imagemagick@6 6.9.7-10
======================
Created with `brew bump-formula-pr`.
---
Please remember to
```
brew mirror imagemagick@6
```
when merging.
> The last release of imagemagick 6 was on Feb 18, 2017 (!), even though they started version 7 in 2011.
FYI that's not true. IMv7 was released in January 2016. When you read IM's changelog, among all the entries with a common version number, only the latest one indicates the actual release.