lfs: import the Facebook git-lfs client extension The purpose of this is the same as the built-in largefiles extension- to handle huge files outside of the normal storage system, generally to keep the amount of data cloned to a lower amount. There are several benefits of implementing the git-lfs protocol, instead of using the largefiles extension: - Bitbucket and Github support (and probably wider support in 3rd party hosting sites in general). [1][2] - The number of hg internals monkey patched are several orders of magnitude lower, so it will be easier to reason about and maintain. Future commands will likely just work, without requiring various wrappers. - The "standin" files are only written to the filelog, not the disk. That should avoid weird edge cases where the largefile and standin files get out of sync. [3] It also avoids the occasional printing of the "hidden" standin file in various messages. - Filesets like size() will work, even if the file isn't present. (It always says 41 bytes for largefiles, whether present or not.) The only place that I see where largefiles comes out on top is that it works with `hg serve` for simple sharing, without external infrastructure. Getting lfs-test-server working was a hassle, and took awhile to figure out. Maybe we can do something to make it work in the future. Long term, I expect that this will be highly preferred over largefiles. But if we are to recommend this to largefile users, there are some UI issues to bikeshed. Until they are resolved, I've marked this experimental, and am not putting a pointer to this in the largefiles help. The (non exhaustive) list of issues I've seen so far are: - It isn't sufficient to just enable the largefiles extension- you have to explicitly add a file with --large before it will pay attention to the configured sizes and patterns on future adds. The justification being that once you use it, you're stuck with it. I've seen people confused by this, and haven't liked it myself. But it's also saved me a few times. Should we do something like have a specific enabling config setting that must be set in the local repo config, so that enabling this extension in the user or system hgrc doesn't silently start storing lfs files? - The largefiles extension adds a repo requirement when the first largefile is committed, so that the extension must always be enabled in the future. This extension is not doing that, and since I only enabled it locally to avoid infecting other repos, I got a cryptic error about missing flag processors when I cloned. Is there no repo requirement due to shallow/narrow clone considerations (or other future advanced things)? - In the (small amount of) reading I've done about the git implementation, it seems that the files and sizes are stored in a tracked .gitattributes file. I think a tracked file for this would be extremely useful for consistency across developers, but this kind of touches on the tracked hgrc file proposal a few months back. - The git client can specify file patterns, not just sizes. - The largefiles extension has a cache directory in the local repo, but also a system wide one. We should probably implement a system wide cache too, so that multiple clones don't have to refetch the files from the server. - Jun mentioned other missing features, like SSH authentication, gc, etc. The code corresponds to c0492b73c7ef in hg-experimental. [4] The only tweaks are to load the extension in the tests with 'lfs=' instead of 'lfs=$TESTDIR/../hgext3rd/lfs', change the import in the *.py test to hgext (from hgext3rd), add the 'testedwith' declaration, and mark it experimental for now. The infinite-push, p4fastimport, and remotefilelog tests were left behind. The devel-warnings for unregistered config options are not corrected yet, nor are the import check warnings. [1] https://www.mercurial-scm.org/pipermail/mercurial/2017-November/050699.html [2] https://bitbucket.org/site/master/issues/3843/largefiles-support-bb-3903 [3] https://bz.mercurial-scm.org/show_bug.cgi?id=5738 [4] https://bitbucket.org/facebook/hg-experimental

run-tests: outputdir also has to be changed if $TESTDIR is not $PWD Following a18eef03d879, running run-tests.py from outside tests/ would lead to the creation of .testtimes and test-*.t.err in $PWD instead of $TESTDIR. This patch fixes that and updates the relevant test.

hgweb: use webutil.commonentry() for nodes (but not for jsdata yet) in /graph This makes graphdata() simpler by using existing code that gets common changeset properties for showing in hgweb. graphdata() is a nested function in graph() that prepares entries for /graph view, but there are two different lists of changesets prepared: "jsdata" for JavaScript-rendered graph and "nodes" for everything else. For "jsdata", properties "node", "user", "age" and "desc" are passed through various template filters because we don't have these filters in JavaScript, so the data has to be prepared server-side. But now that commonentry() is used for producing "nodes" list (and it doesn't apply any filters), these filters need to be added to the appropriate templates (only raw at this moment, everything else either doesn't implement graph or uses JavaScript). This is a bit of refactoring that will hopefully simplify future patches. The end result is to have /graph that only renders the actual graph with nodes and vertices in JavaScript, and the rest is done server-side. This way server-side code can focus on showing a list of changesets, which is easy because we already have /log, /shortlog, etc, and JavaScript code can be simplified, making it easier to add obsolescence graph and other features.

hgweb: check changeset's original branch in graphdata() This piece of code checks if a changeset is the tip of its branch, but as can be seen above in the context, "branch" was prepared for being displayed in hgweb by making it unicode and passing it through url.escape. It's better to use the original ctx.branch().

hgweb: show instabilities of a commit In paper, coal, gitweb and monoblue a new "tag" (or multiple, if there are many instabilities) is added to the same line that has phase, branch, etc of a changeset; in gitweb and monoblue this element has a light red background, in paper and coal the element is black and underlined. In spartan theme instabilities are shown on a separate line. While test-obsolete.t uses first(phasedivergent()) revset to pick a changeset to test, that particular changeset is also an orphan, so two different instability tags are displayed.

context: add instabilities() method to basefilectx This method is now used in webutils.commonentry(), which adds common data items (commit hash, author, date, etc) for rendering changesets in hgweb. Usually, commonentry() is given a changectx as ctx; but in views related to files (e.g. file view, diff, annotate) it's replaced by a filectx, so the latter also needs to have instabilities() method.

run-test: drop 'execfile' usage for 'common-pattern.py' file This is required for Python 3.

run-test: use byte for 'common-pattern.py' path This is required for Python 3.

templates: reword 'back to filelog' link anchor text This anchor text is problematic in two ways: first, the "back to" part assumes that you got to the page showing it via the filelog. This is not necessarily true, as there are other ways to get to that view besides the filelog view, such as for example following the history of lines from a file. Second, it uses "filelog" jargon, which refers to how each file has its own revlog. This is internal jargon that has no business being exposed to the end user. I just reworded this template to improve understanding.

hgweb: show obsolescence status of a commit As with phases, spartan theme shows a simple "obsolete: yes" on its own line (this allows replacing "yes" with something more useful in future, like output of obsfate* template functions). Everywhere else a new "tag" is added to the same line that has phase, branch, etc of a changeset; in gitweb and monoblue the element has gray background, in paper and coal the element is gray with a dashed underline.