patch: add label for coloring the index extended header Just like the summary says, this will colorize the: index 3d3ba4b65e11..57274a0f46b2 100644 line in the diff output.

patch: add index line for diff output This helps highlighting in third-party diff coloring (which assumes git output) and maintains pedantic correctness with diff --git. Tests will be added at the end of the series.

patch: add config knob for displaying the index header This config knob can take an integer between 0 and 40 or a keyword ('none', 'short', 'full') to control the length of hash to output. It will display diffs with the git index header as such, diff --git a/mercurial/mdiff.py b/mercurial/mdiff.py index 112edf7..d6b52c5 100644 We'll put this in the experimental section for now.

bisect: refer directly to bisect() revset predicate in help We have specific syntax for displaying the help text for a particular revset predicate, so let's refer directly to the bisect() revset in the verbose bisect help. It seems likely that the user doesn't care about other revsets at that point, so they will probably not miss the text about the other revset predicates.

tests: use "hg help revisions.<predicate>" instead of grepping We have specific syntax for displaying the help text for a particular revset predicate, so use that instead of grepping through the full output.

help: remove now-redundant pointer to revsets help "hg help revisions" and "hg help revsets" now point to the same text, so drop the revsets reference.

help: eliminate duplicate text for revset string patterns There's no reason to duplicate this so many times, and it's likely an instance will be missed if support for a new pattern is added and documented. The stringmatcher is mostly used by revsets, though it is also used for the 'tag' related templates, and namespace filtering in the journal extension. So maybe there's a better place to document it. `hg help patterns` seems inappropriate, because that is all file pattern matching. While here, indicate how to perform case insensitive regex searches.

revset: add regular expression support to 'desc' This is a case insensitive predicate like 'author', so it conforms to the existing behavior of performing a case insensitive regex.

revset: stop lowercasing the regex pattern for 'author' It was probably unintentional for regex, as the meaning of some sequences like \S and \s is actually inverted by changing the case. For backward compatibility however, the matching is forced to case insensitive.

repair: clean up stale lock file from store backup Since we did a directory rename on the stores, the source repository's lock path now references the dest repository's lock path and the dest repository's lock path now references a non-existent filename. So releasing the lock on the source will unlock the dest and releasing the lock on the dest will no-op because it fails due to file not found. So we clean up the dest's lock manually.

repair: copy non-revlog store files during upgrade The store contains more than just revlogs. This patch teaches the upgrade code to copy regular files as well. As the test changes demonstrate, the phaseroots file is now copied.

repair: migrate revlogs during upgrade Our next step for in-place upgrade is to migrate store data. Revlogs are the biggest source of data within the store and a store is useless without them, so we implement their migration first. Our strategy for migrating revlogs is to walk the store and call `revlog.clone()` on each revlog. There are some minor complications. Because revlogs have different storage options (e.g. changelog has generaldelta and delta chains disabled), we need to obtain the correct class of revlog so inserted data is encoded properly for its type. Various attempts at implementing progress indicators that didn't lead to frustration from false "it's almost done" indicators were made. I initially used a single progress bar based on number of revlogs. However, this quickly churned through all filelogs, got to 99% then effectively froze at 99.99% when it got to the manifest. So I converted the progress bar to total revision count. This was a little bit better. But the manifest was still significantly slower than filelogs and it took forever to process the last few percent. I then tried both revision/chunk bytes and raw bytes as the denominator. This had the opposite effect: because so much data is in manifests, it would churn through filelogs without showing much progress. When it got to manifests, it would fill in 90+% of the progress bar. I finally gave up having a unified progress bar and instead implemented 3 progress bars: 1 for filelog revisions, 1 for manifest revisions, and 1 for changelog revisions. I added extra messages indicating the total number of revisions of each so users know there are more progress bars coming. I also added extra messages before and after each stage to give extra details about what is happening. Strictly speaking, this isn't necessary. But the numbers are impressive. For example, when converting a non-generaldelta mozilla-central repository, the messages you see are: migrating 2475593 total revisions (1833043 in filelogs, 321156 in manifests, 321394 in changelog) migrating 1.67 GB in store; 2508 GB tracked data migrating 267868 filelogs containing 1833043 revisions (1.09 GB in store; 57.3 GB tracked data) finished migrating 1833043 filelog revisions across 267868 filelogs; change in size: -415776 bytes migrating 1 manifests containing 321156 revisions (518 MB in store; 2451 GB tracked data) That "2508 GB" figure really blew me away. I had no clue that the raw tracked data in mozilla-central was that large. Granted, 2451 GB is in the manifest and "only" 57.3 GB is in filelogs. But still. It's worth noting that gratuitous loading of source revlogs in order to display numbers and progress bars does serve a purpose: it ensures we can open all source revlogs. We don't want to spend several minutes copying revlogs only to encounter a permissions error or similar later. As part of this commit, we also add swapping of the store directory to the upgrade function. After revlogs are converted, we move the old store into the backup directory then move the temporary repo's store into the old store's location. On well-behaved systems, this should be 2 atomic operations and the window of inconsistency show be very narrow. There are still a few improvements to be made to store copying and upgrading. But this commit gets the bulk of the work out of the way.

revlog: add clone method Upcoming patches will introduce functionality for in-place repository/store "upgrades." Copying the contents of a revlog feels sufficiently low-level to warrant being in the revlog class. So this commit implements that functionality. Because full delta recomputation can be *very* expensive (we're talking several hours on the Firefox repository), we support multiple modes of execution with regards to delta (re)use. This will allow repository upgrades to choose the "level" of processing/optimization they wish to perform when converting revlogs. It's not obvious from this commit, but "addrevisioncb" will be used for progress reporting.

repair: begin implementation of in-place upgrading Now that all the upgrade planning work is in place, we can start doing the real work: actually upgrading a repository. The main goal of this commit is to get the "framework" for running in-place upgrade actions in place. Rather than get too clever and low-level with regards to in-place upgrades, our strategy is to create a new, temporary repository, copy data to it, then replace the old data with the new. This allows us to reuse a lot of code in localrepo.py around store interaction, which will eventually consume the bulk of the upgrade code. But we have to start small. This patch implements adding new repository requirements. But it still sets up a temporary repository and locks it and the source repo before performing the requirements file swap. This means all the plumbing is in place to implement store copying in subsequent commits.

repair: determine what upgrade will do This commit introduces code for determining what actions/improvements an upgrade should perform. The "upgradefindimprovements" function introduces a mechanism to return a list of improvements that can be made to a repository. Each improvement is effectively an action that an upgrade will perform. Associated with each of these improvements is metadata that will be used to inform users what's wrong and what an upgrade will do. Each "improvement" is categorized as a "deficiency" or an "optimization." TBH, I'm not thrilled about the terminology and am receptive to constructive bikeshedding. The main difference between a "deficiency" and an "optimization" is a deficiency is always corrected (if it deviates from the current config) and an "optimization" is an optional action that goes above and beyond to improve the state of the repository (usually by requiring more CPU during upgrade). Our initial set of improvements identifies missing repository requirements, a single, easily correctable problem with changelog storage, and a set of "optimizations" related to delta recalculation. The main "upgraderepo" function has been expanded to handle improvements. It queries for the list of improvements and determines which of them will run based on the current repository state and user I went through numerous iterations of the output format before settling on a ReST-inspired definition list format. (I used bulleted lists in the first submission of this commit and could not get it to format just right.) Even with the various iterations, I'm still not super thrilled with the format. But, this is a debug* command, so that should mean we can refine the output without BC concerns.