Summary:
Ref T4327. This is general cleanup since I was in this area of the code. Primarily, the Mercurial implementation here was completely broken and wrong:
- It returned only one branch, but a commit can be present on many branches.
- It did not account for multiple branch heads.
- It returned a result implying the branch head pointed at the queried commit, which is no consistent or accurate.
Simplify the amount of API we're dealing with by collapsing this method into the very similar `diffusion.branchquery` method.
Test Plan: Looked at mercurial and git repositories and commits, branch information seemed correct.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4327
Differential Revision: https://secure.phabricator.com/D8003
Summary: Ref T4327. At some point these two very similar classes got introduced. Collapse `DiffusionBranchInformation` into the nearly identical `DiffusionRepositoryRef`, which enjoys slightly more generality and support.
Test Plan: Viewed branch overview and detail pages. Ran `repository refs` and `repository discover`. Grepped for removed symbols.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4327
Differential Revision: https://secure.phabricator.com/D8002
Summary:
Ref T4327. Simplify the git discovery process so I can move it to the DiscoveryEngine, so I can make change parsing testable.
In particular:
- As an optimization, we process closeable branches ("master") first, then process uncloseable branches ("epriestley-devel"). This means that in the common case we can insert a commit as closeable immediately when it is discovered, the first pass through the pipeline will get it right, and the "ref update" step will never need to do any meaningful work.
- Commits which do not initially appear on a closeable branch, but later move to one (via merges or ref moves) will now be caught in the ref update step, have the closeable flag set, and have a message step re-queued.
- We no longer need to do a separate discovery step on closable branches.
- We no longer need to keep track of `seenOnBranches`.
Test Plan: Ran discovery on repositories after pushing commits, got reasonable results.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4327
Differential Revision: https://secure.phabricator.com/D7985
Summary:
Ref T4327. I want to make change parsing testable; one thing which is blocking this is that the Git discovery process is still part of `PullLocal` daemon instead of being part of `DiscoveryEngine`. The unit test stuff which I want to use for change parsing relies on `DiscoveryEngine` to discover repositories during unit tests.
The major reason git discovery isn't part of `DiscoveryEngine` is that it relies on the messy "autoclose" logic, which we never implemented for Mercurial. Generally, I don't like how autoclose was implemented: it's complicated and gross and too hard to figure out and extend.
Instead, I want to do something more similar to what we do for pushes, which is cleaner overall. Basically this means remembering the old branch heads from the last time we parsed a repository, and figuring out what's new by comparing the old and new branch heads. This should give us several advantages:
- It should be simpler to understand than the autoclose stuff, which is pretty mind-numbing, at least for me.
- It will let us satisfy branch and tag queries cheaply (from the database) instead of having to go to the repository. We could also satisfy some ref-resolve queries from the database.
- It should be easier to extend to Mercurial.
This implements the basics -- pretty much a table to store the cursors, which we update only for Git for now.
Test Plan:
- Ran migration.
- Ran `bin/repository discover X --trace --verbose` on various repositories with branches and tags, before and after modifying pushes.
- Pushed commits to a git repo.
- Looked at database tables.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4327
Differential Revision: https://secure.phabricator.com/D7982
Summary: Fixes T3857. Earlier work made this trivial and just left product questions, which I've answered by requiring the daemons to run on reasonable installs.
Test Plan: Ran `bin/search index` and `bin/search index --background`. Observed indexes write in the former case and tasks queue in the latter case. Commented with a unique string on a revision and searched for it a moment later, got exactly one result (that revision), verifying that reindexing works correctly.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T3857
Differential Revision: https://secure.phabricator.com/D7966
Summary: This removes the bulk of the "Form Errors" text, some variations likely exists. These are a bit redundant and space consuming. I'd also like to back ErrorView more into PHUIObjectBox.
Test Plan: Test out the forms, see errors without the text.
Reviewers: epriestley, btrahan
CC: Korvin, epriestley, aran, hach-que
Differential Revision: https://secure.phabricator.com/D7924
Summary: Two basic changes here, first we fixed up the Diffusion headers to roll out more PHUIObjectBoxes. Second we added some specific styles for when Errors are inside an ObjectBox at the first position.
Test Plan: Tested a number of different layouts for browsing respositories as well as wherever I could find cases with PHUIObjectBox Form Errors (see images attached). Still some minor tightening due after this diff, but didnt want to overload it.
Reviewers: epriestley, btrahan
Reviewed By: epriestley
CC: Korvin, epriestley, aran
Differential Revision: https://secure.phabricator.com/D7914
Test Plan: Created comments with 'silent' both true and empty, received notifcation for only the latter.
Reviewers: epriestley, #blessed_reviewers
Reviewed By: epriestley
CC: Korvin, epriestley, aran
Differential Revision: https://secure.phabricator.com/D7916
Summary:
Updates table design to use new standards, work well in PHUIObjectBox. Fixes T4142
Comma
Test Plan: Tested on Diffusion, Settings, will roll out to more places soon
Reviewers: epriestley, btrahan
CC: Korvin, epriestley, aran
Maniphest Tasks: T4142
Differential Revision: https://secure.phabricator.com/D7901
Summary:
Fixes T4276. This adds "Change is enormous" to pre-commit content rules so we can, e.g., just reject these and not worry about them elsewhere.
Also, use the same numeric limits across the mechanisms so there's a consistent definition of an "enormous" changeset.
Test Plan:
- Set enormous limit to 15 bytes, pushed some changes, got blocked by a rule.
- Set it back, pushed OK.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4276
Differential Revision: https://secure.phabricator.com/D7887
Summary:
Ref T4276. When a change is larger than 2GB, PHP can not read the entire change into a string, so Herald can not process it.
Additionally, we already have a time limit for practical reasons, but it's huge (probably incorrectly). To deal with these things:
- Add an optional byte limit to `diffusion.rawdiffquery`.
- Make the query with a 1GB limit.
- Reduce the diff timeout from 15 hours to 15 minutes.
- Add a "Changeset is enormous" field. This field is true for changes which are too large to process.
This generally makes behaviors more sane:
- We'll always make progress in Herald in a reasonable amount of time.
- Installs can write global rules to handle (or reject) these types of changes.
Test Plan: Set limit to 25 bytes instead of 1GB and ran test console on various changes.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4276
Differential Revision: https://secure.phabricator.com/D7885
Summary:
Fixes T4189. Ref T4151. Allows repositories to have additional custom hooks for operations which can't be expressed with Herald (one such operation is lint).
This adds only local hook directories, since they're easier to use with existing hooks than global directories. I might add global directories eventually.
This doesn't support Mercurial since we have no demand for it and it's more complicated (we lose compatibility and power by just dropping a `hooks.d/` somewhere).
Test Plan:
- Pulled hosted SVN and Git repos to verify the hook directories generate correctly.
- Added a variety of hooks to the hook directories (echo + pass, fail).
- Pushed commits and verified the hooks fired (output expected info, or failed).
- Verified push log reflected the correct error code ("3", external) and detail ("nope.sh") when rejecting.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4151, T4189
Differential Revision: https://secure.phabricator.com/D7884
Summary:
Fixes T4264. Adds:
- New "Repository's projects" field to Herald pre-commit rules, so you can write global rules which act based on projects.
- Allows pre-ref/pre-content rules to bind to projects, and fire for all repositories in that project, so users with limited power can write rules which apply to many repositories.
- The pre-ref and pre-content classes were starting to share a fair amount of code, so I made them both extend an abstract base class.
Test Plan: Wrote new pre-ref and pre-content rules bound to projects, then pushed commits into repositories in those projects and not in those projects. The "repository projects" field populated, and the rules fired for repositories in the relevant projects.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4264
Differential Revision: https://secure.phabricator.com/D7883
Summary: Ref T4264. Ref T2628. Ref T3102. Allows you to associate repositories with projects. In the future, you'll be able to write Herald object rules against projects, use Herald fields like "Repository's projects", and search by project.
Test Plan: See screenshots.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T3102, T4264, T2628
Differential Revision: https://secure.phabricator.com/D7881
Summary:
Repositories currently have a no-UI "shortcut" feature which is only used by Facebook (and I'm not sure it's even used). As implemented, this feature is policy-oblivious and kind of nonsensical. Throw it away.
I'm open to reimplementing this, but I want to see some level of interest in it before I do. The new implementation would add shortcuts to each repository, similar to how mirrors work. My original plan was to follow this up with such an implementation (it's half-implemented in my sandbox), but as I worked through it I'm not sure it's really valuable.
Test Plan: Browsed repository list, grep.
Reviewers: btrahan
Reviewed By: btrahan
CC: FacebookPOC, aran
Differential Revision: https://secure.phabricator.com/D7862
Summary: Currently we markup `rXabcd`, but not `rX` on its own. Mark these up as repository object names.
Test Plan: Typed `rPOEMS`, `rPOEMS1`, `rPOEMS139893189`, etc.
Reviewers: btrahan, dctrwatson
Reviewed By: btrahan
CC: aran, poop
Differential Revision: https://secure.phabricator.com/D7859
Summary:
Fixes T4242. It's currently possible to set nonsense defaults and create repositories with unintended policies, because policy configuration isn't part of creation. Instead:
- put a policy page into the creation workflow;
- require the selection of valid policies (i.e., prevent creating a repository you can't view / edit).
Test Plan:
- Created imported and hosted repositories, hit policy selection.
- Edited policies of existing repositories.
- Tried to set nonsense policies.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4242
Differential Revision: https://secure.phabricator.com/D7856
Summary:
Ref T4264. Allows you to create "Object" rules, in addition to Global and Personal rules. If you choose to create an Object rule, you'll be prompted to select an object on a new screen. You must be able to edit and object in order to create rules for it.
Ref T3506. This makes "All" the default filter for the transcript view, which should reduce confusion on smaller installs.
Test Plan:
- Created non-object rules.
- Created object rules.
- Triggered object rules against matching and unmatching objects.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T3506, T4264
Differential Revision: https://secure.phabricator.com/D7853
Summary: Ref T4264. Lays the groundwork for new "Object" rule types. Prevents personal "Hook" rules, which don't make any sense.
Test Plan: Created new Maniphest (global/personal available) and Ref Hook (global only) rules.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4264
Differential Revision: https://secure.phabricator.com/D7852
Summary: Some discussion on IRC. This is more consistent with other disabled items, which are click-to-explain.
Test Plan: Viewed UI, clicked link.
Reviewers: btrahan, dctrwatson, asherkin
Reviewed By: asherkin
CC: aran
Differential Revision: https://secure.phabricator.com/D7857
Summary:
Fixes T4270. When you download raw file content, diffs, and patches we currently give them default (all users) visibility.
Instead, bind them to the repository or revision in question.
(This code could use a bit of cleanup at some point.)
Test Plan: Hit the patch and content download links in Diffusion and the patch download link in Differential, got restricted files with accurate policy bindings.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4270
Differential Revision: https://secure.phabricator.com/D7849
Summary: Ref T4264. Instead of a dropdown, make this step more informative.
Test Plan: {F93928}
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4264
Differential Revision: https://secure.phabricator.com/D7846
Summary: If `0` isn't an ancestor of the current branch, the `0::x` construction fails. This is uncommon, but not wildly unreasonable. The `ancestors()` construction is simpler anyway.
Test Plan: Viewed some `hg` repos locally (change history, file history) without anything suspicious cropping up.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Differential Revision: https://secure.phabricator.com/D7844
Summary:
Ref T4195. A legitimate rule which needs this field is "do not allow commits as root". Interestingly, we have exactly one commit as root in each Phabricator, Arcanist and libphutil.
Since the committer and author don't need to be Phabricator accounts (just the Pusher), the existing "Committer" and "Author" fields can't express this rule (they'll be empty).
Test Plan: {F93406}
Reviewers: btrahan
Reviewed By: btrahan
CC: SEJeff, aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7841
Summary:
Fixes T4195. Allows you to write a rule against a commit's branches.
This completes outstanding work on T4195.
Test Plan: Pushed to Git and Mercurial repositories and verified branches were selected correctly by examining transcripts.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7820
Summary:
Fixes T4257. The `hg heads` command exits with an error code and no output in an empty repository.
Just ignore the error code: we don't have a great way to distinguish between errors, and we ran another `hg` command moments before, so we have at least some confidence it isn't a PATH sort of thing.
Test Plan: Created a new Mercurial repository and pushed to hit the error in T4257. Applied this fix and got a clean push with an accurate push log.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4257
Differential Revision: https://secure.phabricator.com/D7817
Summary:
Ref T4195. This allows you to write rules which disallow merge commits.
Also make the reject message a little more useful.
Test Plan:
remote: This push was rejected by Herald push rule H27.
remote: Change: commit/daed0d448404
remote: Rule: No Merges
remote: Reason: No merge commits allowed. If you must push a merge, include "@force-merge" in the commit message.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7809
Summary: Ref T4195. Ref T2783. We have an old-school implementation of this; move it into a LowLevel query and make callers all run through Conduit. I need the LowLevel query for hooks, to implement an "is merge commit" Herald rule.
Test Plan:
- Ran query via Conduit for SVN, Mercurial, Git.
- Parsed a commit which closed a revision, attach/closed worked correctly.
- Browsed Diffusion.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195, T2783
Differential Revision: https://secure.phabricator.com/D7808
Summary: Refs T4195. Fixes T3936. You can't currently write rules like "block commits unless they're attached to an **accepted** revision"; allow that.
Test Plan: Pushed commits into a rule with this field, saw it work / not crash.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran, mbishopim3
Maniphest Tasks: T3936, T4195
Differential Revision: https://secure.phabricator.com/D7807
Summary: Ref T4195. Allows you to write revision-based commit hooks, e.g. block all commits with no corresponding revision.
Test Plan:
Here's are the fields populating:
{F90989}
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7806
Summary: Ref T4195. I need to query commit metadata to figure out which revision a commit is associated with. Move this out of the MessageParser so the code can be called from the HookEngine.
Test Plan: Used `reparse.php` to reparse a variety of SVN, Mercurial and Git commits. Used `var_dump()` to verify sensible fields were returned.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7805
Summary: Ref T4195. I need this for the Herald pre-commit rules, and it generally simplifies things.
Test Plan: Used `reparse.php` plus `var_dump()` to inspect refs in Git, Mercurial and SVN repos. They all looked correct and reparsed correctly.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7804
Summary:
There's no particular reason to allow the user to edit the clone URI field in Diffusion; editing it has no meaning and if you fat finger the keyboard, it's quite possible that the user will either accidentally clear and/or modify the URI before copying (bit me this morning).
Adding a readonly attribute to the input field allows the same benefit (URI is easily selectable) while preventing such accidental input. Fixes T4246.
Test Plan: Verified that the desired behavior is present in both Chrome, Safari, and Firefox. Field remains selectable with one click, but field is not editable.
Reviewers: epriestley, #blessed_reviewers
Reviewed By: epriestley
CC: Korvin, epriestley, aran
Maniphest Tasks: T4246
Differential Revision: https://secure.phabricator.com/D7810
Summary: Ref T4195. Adds "Author" and "Committer" fields.
Test Plan:
Created a rule using these fields:
{F90897}
...then pushed git, mercurial and svn commits and verified the correct values populated in the transcript:
{F90898}
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7802
Summary:
Ref T4195. To implement the "Author" and "Committer" rules, I need to resolve author/committer strings into Phabricator users.
The code to do this is currently buried in the daemons. Extract it into a standalone query.
I also added `bin/repository lookup-users <commit>` to test this query, both to improve confidence I'm getting this right and to provide a diagnostic command for users, since there's occasionally some confusion over how author/committer strings resolve into valid users.
Test Plan:
I tested this using `bin/repository lookup-users` and `reparse.php --message` on Git, Mercurial and SVN commits. Here's the `lookup-users` output:
>>> orbital ~/devtools/phabricator $ ./bin/repository lookup-users rINIS3
Examining commit rINIS3...
Raw author string: epriestley
Phabricator user: epriestley (Evan Priestley )
Raw committer string: null
>>> orbital ~/devtools/phabricator $ ./bin/repository lookup-users rPOEMS165b6c54f487c8
Examining commit rPOEMS165b6c54f487...
Raw author string: epriestley <git@epriestley.com>
Phabricator user: epriestley (Evan Priestley )
Raw committer string: epriestley <git@epriestley.com>
Phabricator user: epriestley (Evan Priestley )
>>> orbital ~/devtools/phabricator $ ./bin/repository lookup-users rINIH6d24c1aee7741e
Examining commit rINIH6d24c1aee774...
Raw author string: epriestley <hg@yghe.net>
Phabricator user: epriestley (Evan Priestley )
Raw committer string: null
>>> orbital ~/devtools/phabricator $
The `reparse.php` output was similar, and all VCSes resolved authors correctly.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T1731, T4195
Differential Revision: https://secure.phabricator.com/D7801
Summary: Ref T4195. Even though we use `svnlook` in the hook itself, I need this query elsewhere, so provide it and merge the classes into one which does the right thing.
Test Plan:
- Used `reparse.php` to reparse messages for Git, SVN and Mercurial commits, using `var_dump()` to examine the commit refs for sanity.
- Used `reparse.php` to reparse changes for an SVN commit.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7800
Summary: There were a number of places that were generating nonsense queries for both hosted and non-hosted subversion repositories.
Test Plan: Attempted several activities in Diffusion with both a hosted and non-hosted subversion repository, including viewing various types of diffs and raw files.
Reviewers: epriestley, #blessed_reviewers
Reviewed By: epriestley
CC: Korvin, epriestley, aran
Differential Revision: https://secure.phabricator.com/D7799
Summary: If you push a large binary and the data crosses multiple data frames, we can end up in a loop in the parser.
Test Plan:
After this change, I was able to push a 95MB binary in 7s, which seems reasonable:
>>> orbital ~/repos/INIS $ svn st
A large2.bin
>>> orbital ~/repos/INIS $ ls -alh
total 390648
drwxr-xr-x 6 epriestley admin 204B Dec 18 17:14 .
drwxr-xr-x 98 epriestley admin 3.3K Dec 16 11:19 ..
drwxr-xr-x 7 epriestley admin 238B Dec 18 17:14 .svn
-rw-r--r-- 1 epriestley admin 80B Dec 18 15:07 README
-rw-r--r-- 1 epriestley admin 95M Dec 18 16:53 large.bin
-rw-r--r-- 1 epriestley admin 95M Dec 18 17:14 large2.bin
>>> orbital ~/repos/INIS $ time svn commit -m 'another large binary'
Adding (bin) large2.bin
Transmitting file data .
Committed revision 25.
real 0m7.215s
user 0m5.327s
sys 0m0.407s
>>> orbital ~/repos/INIS $
There may be room to improve this by using `PhutilRope`.
Reviewers: wrotte, btrahan, wotte
Reviewed By: wotte
CC: aran
Differential Revision: https://secure.phabricator.com/D7798
Summary: Ref T4195. Same as D7793, but for mercurial. (As usual, SVN needs some goofy nonsense instead, so the next diff will just make this field work.)
Test Plan: Ran `reparse.php` on Git and Mercurial commits, var_dump'd the output and it looked correct.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7795
Summary: Ref T4195. I need to issue this command from the pre-commit hook to get commit bodies for hooks.
Test Plan: Ran `reparse.php --message --trace` and dumped the $ref, which looked correct.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7793
Summary: We currently have a lot of calls to `addCrumb(id(new PhabricatorCrumbView())->...)` which can be expressed much more simply with a convenience method. Nearly all crumbs are only textual.
Test Plan:
- This was mostly automated, then I cleaned up a few unusual sites manually.
- Bunch of grep / randomly clicking around.
Reviewers: btrahan, chad
Reviewed By: btrahan
CC: hach-que, aran
Differential Revision: https://secure.phabricator.com/D7787
Summary: Ref T4195. Add Mercurial support to the content hook phase.
Test Plan:
Here are some `commit` push logs for a Mercurial repo:
{F90689}
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7792
Summary: Ref T4195. Adds support for diff content rules.
Test Plan: Pushed SVN and Git changes through, saw them generate reasonable transcripts. Mercurial still isn't hooked up to this phase.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7791
Summary: Ref T4195. This doesn't provide any interesting fields yet (content, affected paths, commit message) but fires the hook correctly.
Test Plan: Added a blocking hook and saw it fire.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7789
Summary:
Ref T615. Ref T4237. With `--debug`, Mercurial will echo an "ignoring untrusted configuration option" warning **to stdout** if `.hgrc` has the wrong owner.
However, we need `--debug` to make `{parents}` usable, at least until the patches I got into the upstream are widely deployed. So after getting `--debug` output, strip off any leading warnings.
These warnings should always be in English, at least, since we set `LANG` explicitly.
Test Plan: Unit tests. @asherkin, maybe you can confirm this? I can't actually get the warning, but I think my `hg` in PATH is just a bit out of date.
Reviewers: asherkin, btrahan
Reviewed By: asherkin
CC: asherkin, aran
Maniphest Tasks: T615, T4237
Differential Revision: https://secure.phabricator.com/D7784
Summary: Ref T4195. SVN has no such thing as refs (I was thinking about writing a quasi-ref anyway like `HEAD: r23 -> r24`, but I'm not sure it would actually be useful). And content is very easy to build.
Test Plan: Pushed some stuff to SVN, got logs from it.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7766
Summary: Ref T4195. This doesn't actually work like I thought it did: it only fires locally, when you run `hg tag`. Mercurial tags are also weird and basically don't make any sense and everyone should use bookmarks instead. We could implement some flavor of this eventually, but I'd like to see users request it first. They can implement their own with content-based hooks once those work, anyway.
Test Plan: This code didn't do anything.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7765
