transplant: improve documentation

transplant: clarify what --branch do - it has nothing to do with branches --branch specifies heads and has nothing to do with named branches, and it only deals with topological branches to the same extent as all other DAG operations do.

import: inline checkexact function We have a sngle call now, no need to make it a function.

import: factor out checkexact The two calls are strictly identical. We can simply move it after the if/else clause.

amend: fix unlocking order - first lock then wlock

codingstyle: remove trailing spaces in various text files Better do it once than see random changes in diffs later.

tests: run check-code on Python files without .py extension

histedit: move outgoing processing to its own function Every piece of code extracted from the main command is a win. We simplify changeset determination in the process. Parent ceases being a list before becoming a node. We how have a root variable containing a node all the time.

histedit: move all arguments checks to the beginning of the command This changeset move all checks and raises related to arguments validation to the top of the file. This gathers all the logic in one place and clarifies the code doing actual work. This paves the way for splitting this gigantic function in separated functions. A `goal` variable is introduced in the process. It holds the action to be done by this invocation (new, continue or abort). An invalid invocation is found in the process (the new code is a bit stricter).

histedit-test: generalise --commands "-" usage This is simpler than temporary file version. There some minor test changes since commit messages are no longer modifed. There is still some tests using --commands with a real file.

histedit: allow "-" as a command file When "-" is specified as a command file, we read rules from stdin. Alter a single test to demo the behavior, but most of them could benefit from this. There is minor change in test output resulting from the fact we no longer change log messages.

histedit: properly handle --continue on empty fold When all changes from the fold have been dropped, the --continue code was confused. This changeset handles this case. The test for this case existed but was broken.

histedit-test: replace obscure python script by a plain file One of the tests uses a python script to edit the histedit commands on the fly. It was hard to read and likely to break. This is replaced by a plain command file. Doing so made me discover that the python script is incorrect. The "+6" regexp never matched because the revision number is wrong. This error is kept in the replacement for now. Fixing the histedit command triggers a traceback in histedit. A later changeset will fix the error and restore the intended test.

test: improve documentation of some histedit tests Each test section is clearly separated from the others and gains some helpful documentation.

test: use a lighter log style in histedit test The default log displays a log of information that is useless for histedit tests. Having a cleaner log help readability of those tests a lot. This does not change anything to the test semantic.

subrepo: add regression test for issue3870

subrepo: clone of git sub-repository creates incorrect git branch (issue3870) Mercurial handles git subrepos by incorrect way. If the mercurial repo has a git sub-repo and somebody started a new branch in the subrepo and push it into git, the next one who will clone the whole repo will get incorrect branch name in the git subrepo.

dispatch: print 'abort:' when a pre-command hook fails (BC) This also changes the exit code from whatever the hook returned to 255. This brings it in line with all the other hooks that abort.

largefiles: don't hash all largefiles when initializing a lfdirstate The largefiles will be hashed on demand if necessary ... and sometimes it isn't necessary.

largefiles: use filechunkiter for iterating largefile when serving getlfile The default file iterator is line based and will give odd chunk sizes - often very short and relatively expensive.

largefiles: stat all largefiles in one batch before downloading This avoids a lot of expensive roundtrips to remote repositories ... but might be slightly slower for local operations. This will also change some aborts on missing files to warnings. That will in some situations make it possible to continue working on a repository with missing largefiles.

largefiles: 'put' should store 'source' file in under 'hash', also in localstore

largefiles: getlfile must hit end of HTTP chunked streams to reuse connections We did read the exactly the right number of bytes from the response body. But if the response came in chunked encoding then that meant that the HTTP layer still hadn't read the last 0-sized chunk and expected the app layer to read more data from the stream. The app layer was however happy and sent another request which had to be sent on another HTTP connection while the old one was lingering until some other event closed the connection. Adding an extra read where we expect to hit the end of file makes the HTTP connection ready for reuse. This thus plugs a real socket leak. To distinguish HTTP from SSH we look at self's class, just like it is done in putlfile.

largefiles: drop limitreader, use filechunkiter limit filechunkiter.close was a noop.

largefiles: move protocol conversion into getlfile and make it an iterable Avoid the intermediate limitreader and filechunkiter between getlfile and copyandhash - return the right protocol and put the complexity where it better can be managed.

largefiles: don't close the fd passed to store._getfile

largefiles: remove blecch from lfutil.copyandhash - don't close the passed fd

largefiles: drop lfutil.blockstream - use filechunkiter like everybody else The old chunk size is kept - just to avoid changing it.

largefiles: refactoring - use findfile in localstore._getfile

largefiles: refactoring - return hex from _getfile and copyandhash

largefiles: refactoring - create destination dir in lfutil.link

summary: clear "commonincoming" also if branches are different Before this patch, "commonincoming" calculated by "discovery.findcommonincoming()" is cleared, only if "default" URL without branch part (tail "#branch" of URL) differs from "default-push" URL without branch part. But common revisions in "commonincoming" calculated for a branch doesn't include ones for another branch, even if URLs without branch part are same. The result of "discovery.findcommonoutgoing()" invocation with such "commonincoming" becomes incorrect in some cases. This patch clears "commonincoming", also if branch part of "default" differs from one of "default-push". To avoid redundant looking up: - "ui.expandpath('default')" and "ui.expandpath('default-push', 'default')" are not compared directly, even though they contain branch information, because they are not yet normalized by "hg.parseurl()": tail "/" of path, for example - "commonincoming" is not cleared, if branch isn't specified in "default" URL, because such "commonincoming" contains common revisions for all branches This patch also tests "different path, same branch" pattern to check careless degrading around comparison between source and destination.

summary: make "incoming" information sensitive to branch in URL (issue3830) Before this patch, "incoming" information of "hg summary --remote" is not sensitive to the branch specified in the URL of the destination repository, even though "hg pull"/"hg incoming" are so. Invocation of "discovery.findcommonincoming()" without "heads" argument treats revisions on branches other than the one specified in the URL as incoming ones unexpectedly. This patch looks head revisions, which are already detected by "hg.addbranchrevs()" from URL, up against "other" repository, and invokes "discovery.findcommonincoming()" with list of them as "heads" to limit calculation of incoming revisions.

histedit: make "hg histedit" sensitive to branch in URL Before this patch, "hg histedit" are not sensitive to the branch specified in the URL of the destination repository, even though "hg push"/"hg outgoing" are so: Invocation of "discovery.findcommonoutgoing()" without "onlyheads" argument treats revisions on branches other than the one specified in the URL as outgoing ones unexpectedly. This patch specifies list of head revisions, which are already detected by "hg.addbranchrevs()" from URL and looked up against local repository, as "onlyheads" to "discovery.findcommonoutgoing()" to limit calculation of outgoing revisions.

summary: make "outgoing" information sensitive to branch in URL (issue3829) Before this patch, "outgoing" information of "hg summary --remote" is not sensitive to the branch specified in the URL of the destination repository, even though "hg push"/"hg outgoing" are so: Invocation of "discovery.findcommonoutgoing()" without "onlyheads" argument treats revisions on branches other than the one specified in the URL as outgoing ones unexpectedly. This patch looks head revisions, which are already detected by "hg.addbranchrevs()" from URL, up against local repository, and invokes "discovery.findcommonoutgoing()" with list of them as "onlyheads" to limit calculation of outgoing revisions.

annotate: increase refcount of each revisions correctly (issue3841) Before this patch, refcount (managed in "needed") of parents of each revisions in "visit" is increased, only when parent is not annotated yet (examined by "p not in hist"). But this causes less refcount of the revision like "A" in the tree below ("A" is assumed as the second parent of "C"): A --- B --- C \ / \-----/ Steps of annotation for "C" in this case are shown below: 1. for "C" 1.1 increase refcount of "B" 1.2 increase refcount of "A" (=> 1) 1.3 defer annotation for "C" 2. for "A" 2.1 annotate for "A" (=> put result into "hist[A]") 2.2 clear "pcache[A]" ("pcache[A] = []") 3. for "B" 3.1 not increase refcount of "A", because "A not in hist" is False 3.2 annotate for "B" 3.3 decrease refcount of "A" (=> 0) 3.4 delete "hist[A]", even though "A" is still needed by "C" 3.5 clear "pcache[B]" 4. for "C", again 4.1 not increase refcount of "B", because "B not in hist" is False 4.2 increase refcount of "A" (=> 1) 4.3 defer annotation for "C" 5. for "A", again 5.1 annotate for "A" (=> put result into "hist[A]", again) 5.2 clear "pcache[A]" 6. for "C", once again 6.1 not increase refcount of "B", because "B not in hist" is False 6.2 not increase refcount of "A", because "A not in hist" is False 6.3 annotate for "C" 6.4 decrease refcount of "A", and delete "hist[A]" 6.5 decrease refcount of "B", and delete "hist[B]" 6.6 clear "pcache[C]" At step (5.1), annotation for "A" mis-recognizes that all lines are created at "A", because "pcache[A]" already cleared at step (2.2) prevents from scanning ancestors of "A". So, annotation for "C" or its descendants loses information about "A" or its ancestors. The root cause of this problem is that refcount of "A" is decreased at step (3.3), even though it isn't increased at step (3.1). To increase refcount correctly, this patch increases refcount of each parents of each revisions: - regardless of "p not in hist" or not, and - only once for each revisions in "visit" (by "not pcached") In fact, this problem should occur only on legacy repositories in which a filelog includes the merging between the revision and its ancestor (as the second parent), because: - tree is scanned in depth-first without such merging, revisions in "visit" refer different revisions as parent each other - recent Mercurial doesn't allow such merging changelog and manifest can include such merging someway, but filelogs can't, because "localrepository._filecommit()" converts such merging request to linear history. This patch tests merging cases below: these cases are from filelog of "mercurial/commands.py" in the repository of Mercurial itself. - both parents are same 10 --- 11 --- 12 \_/ filelogrev: changesetid: 10 00ea3613f82c 11 fc4a6e5b5812 12 4f802588cdfb - the second parent is also ancestor of the first one 37 --- 38 --- 39 --- 40 \________/ filelogrev: changesetid: 37 f8d56da6ac8f 38 38919e1c254d 39 d3400605d246 40 f06a4a3b86a7

annotate: reuse already calculated annotation Before this patch, annotation is re-calculated even if it is already calculated. This may cause unexpected annotation, because already cleared "pcache" ("pcache[f] = []") prevents from scanning ancestors. This patch reuses already calculated annotation if it is available. In fact, "reusable" situation should be seen only on legacy repositories in which a filelog include the merging between the revision and its ancestor, because: - tree is scanned in depth-first without such merging, annotation result should be released soon - recent Mercurial doesn't allow such merging changelog and manifest can include such merging someway, but filelogs can't, because "localrepository._filecommit()" converts such merging request to linear history.

log: fix behavior with empty repositories (issue3497) Make output in this special case consistent with general case one.

merge with crew

revlog: don't cross-check ancestor result against Python version

parsers: a C implementation of the new ancestors algorithm The performance of both the old and new Python ancestor algorithms depends on the number of revs they need to traverse. Although the new algorithm performs far better than the old when revs are numerically and topologically close, both algorithms become slow under other circumstances, taking up to 1.8 seconds to give answers in a Linux kernel repo. This C implementation of the new algorithm is a fairly straightforward transliteration. The only corner case of interest is that it raises an OverflowError if the number of GCA candidates found during the first pass is greater than 24, to avoid the dual perils of fixnum overflow and trying to allocate too much memory. (If this exception is raised, the Python implementation is used instead.) Performance numbers are good: in a Linux kernel repo, time for "hg debugancestors" on two distant revs (24bf01de7537 and c2a8808f5943) is as follows: Old Python: 0.36 sec New Python: 0.42 sec New C: 0.02 sec For a case where the new algorithm should perform well: Old Python: 1.84 sec New Python: 0.07 sec New C: measures as zero when using --time (This commit includes a paranoid cross-check to ensure that the Python and C implementations give identical answers. The above performance numbers were measured with that check disabled.)

revlog: choose a consistent ancestor when there's a tie Previously, we chose a rev based on numeric ordering, which could cause "the same merge" in topologically identical but numerically different repos to choose different merge bases. We now choose the lexically least node; this is stable across different revlog orderings.

ancestor: a new algorithm that is faster for nodes near tip Instead of walking all the way to the root of the DAG, we generate a set of candidate GCA revs, then figure out which ones will win the race to the root (usually without needing to traverse all the way to the root). In the common case of nodes that are close to each other in both revision number and topology, this is usually a big win: it makes "hg --time debugancestors" up to 9 times faster than the more general ancestor function when measured on heads of the linux-2.6 hg repo. Victory is not assured, however. The older function can still win by a large margin if one node is much closer to the root than the other, or by a much smaller amount if one is an ancestor of the other. For now, we've also got a small paranoid harness function that calls both ancestor functions on every input and ensures that they give equivalent answers. Even without the checker function, the old ancestor function needs to stay alive for the time being, as its generality is used by context.filectx.merge.

update: allow dirty update to foreground (successors) Update to "foreground" are no longer seen as cross branch update. "Foreground" are descendants or successors (or successors of descendants (or descendant of successors (etc))). This allows to update with uncommited changes that get automatically merged. This changeset is a small step forward. We want to allow dirty update to "background" (precursors) and takes obsolescence in account when finding the default update destination. But those requires deeper changes and will comes in later changesets.

obsolete: extract foreground computation from bookmark.validdest This foreground logic will be reused by update logic.

destroyed: invalidate phraserevs cache in all case (issue3858) When revisions are destroyed, the `phaserevs` cache becomes invalid in most case. This cache hold a `{rev => phase}` mapping and revision number most likely changed. Since 1c8e0d6ac3b0, we filter unknown phases' roots after changesets destruction. When some roots are filtered the `phaserevs` cache is invalidated. But not if none root where destroyed. We now invalidate the cache in all case filtered root or not. This bug was a bit tricky to reproduce as in most case we either: * rebase a set a draft changeset including root (phaserev invalidated) * strip tip-most changesets (no re-numbering of revision) Note that the invalidation of `phaserevs` are not strictly needed when only tip-most part of the history have been destroyed. But I do not expect the overhead to be significant.

largefiles: deprecate --all-largefiles for pull The same can be achieved with --lfrev pulled() and we shouldn't advertise unnecessary command line options.

largefiles: implement pull --all-largefiles as a special case of --lfrev

largefiles: drop --cache-largefiles again This goes a step further than d69585a5c5c0 and backs out the unreleased --cache-largefiles option. The same can be achieved with --lfrev heads(pulled()) and we shouldn't introduce unnecessary command line options.

largefiles: introduce pulled() revset expression for use in --lfrev This provides a general way to do what already can be done with --all-largefiles and --cache-largefiles.

largefiles: introduce pull --lfrev option The revset will be evaluated after the changesets has been pulled, and missing largefiles from matching revisions will be pulled to the local caches. This in combination with revsets will make it possible to specify different strategies for pulling largefiles. The revset expressions used for this option might be quite complex and will probably be most useful from scripts or an alias ... but less complicated than configuring hooks.

largefiles: refactor overridepull internals

largefiles: introduce lfpull command for pulling missing largefiles

largefiles: update help Some clarifications, and some clean-up after --cache-largefiles was introduced.

largefiles: fix cat of non-largefiles from subdirectory We were calling back to the original commands.cat from inside the walk loop that handled and filtered out largefiles. That did however happen with file paths relative to repo root and the original cat would fail when it applied its own walk and match on top of that. Instead we now duplicate and modify the code from commands.cat and patch it to handle both normal and largefiles. A change in test output shows that this also makes the exit code with largefiles consistent with the normal one in the case where one of several specified files are missing. This also fixes the combination of --output and largefiles.

largefiles: don't store whole file in memory for 'cat'

mergetools: rename 'base' to 'merged' in meld This makes it clear which panel is the target of the merge operation.

mergetools: avoid losing the merged version with meld Add -o $output. When using Meld as intended (merge from left and right into the center panel), the merged version is written to the wrong file without this option ($base, a temporary file, which is ignored by Mercurial). Add meld.check=changed as a secondary safety net.

templatekw: add default styles for hybrid types (issue3887) This allows elements like file_copies to be printed as 'name (source)' when used with join.

largefiles: improve repo wrapping detection Before this patch, repo wrapping detection in "reposetup()" of largefiles can detect only limited repo wrapping: replacing target functions by another one named as "wrap". So, it can't detect repo wrapping even in recommended style: replacing "__class__" of repo by derived class. This patch can detect repo wrapping in both styles below: - replacing "__class__" of repo by derived class (recommended style): class derived(repo.__class__): def push(self, *args, **kwargs): return super(derived, self).push(*args, **kwargs) repo.__class__ = derived - replacing function of repo by another one (not recommended style): orgpush = repo.push def push(*args, **kwargs): return orgpush(*args, **kwargs) repo.push = push

hgweb: respond HTTP_NOT_FOUND when an archive request does not match any files

archive: raise error.Abort if the file pattern matches no files Note that we could raise this exception even if no pattern were specified, but the revision contained no files. However this should not happen in practice since in that case commands.py/archive would exit earlier with an "no working directory: please specify a revision" error message instead.

ui: add 'force' parameter to traceback() to override the current print setting This will allow a current traceback.print_exc() call in dispatch to be replaced with ui.traceback() even if --traceback was not given on the command line.

ui: add support for fully printing chained exception stacks in ui.traceback() Currently, only SubrepoAbort has a cause chained to it.

subrepo: chain the original exception to SubrepoAbort The tracebacks in subrepos are truncated at the point where the original exception is caught and SubrepoAbort is raised in its place since 9e3910db4e78. That hides the most relevant subrepo methods when an error occurs. Python 2.x doesn't support chaining exceptions, so it is manually done here for manual printing later.

debugrebuildstate: rename to debugrebuilddirstate There is a lot of state, but this command is for rebuilding the dirstate.

debugstate: rename to debugdirstate There is a lot of state, but this command is for debugging the dirstate.

debugrebuildstate: clarify that rev can't be specified without -r -r has a default value of '' in the command line. The function default value of 'tip' is thus never used and any attempt at specifying revisions without -r will fail. It seems like then intended behavior was that 'hg debugrebuildstate' without any parameters should set the parents to tip. That would be very confusing now when the command primarily is used to recover from incorrect stat info. It is apparently undocumented that '' is the same as '.' ... unless it is passed in a place where revsets are used.

check-code: check txt files for trailing whitespace

check-code: catch trailing space in comments

spelling: fix typos and spelling errors

wireproto: clarify cryptic 'remote: unsynced changes' error message on push The message was not very much to the point and did not in any way help an ordinary user. 'repository changed while preparing/uploading bundle - please try again' is more correct, gives the user some understanding of what is going on, and tells how to 'recover' from the situation. The 'bundle' aspect could be seen as an implementation detail that shouldn't be mentioned, but I think it helps giving an exact error message. The message could still leave the user wondering why Mercurial doesn't lock the repo and how unsafe it thus is. Explaining that is however too much detail.

export: export working directory parent by default A common usecase for export is to preview the patch that will be patchbombed or to see what changed in a revision found by bisect. Showing the working directory parent is thus a useful and obvious default.

commit: allow closing "non-head" changesets Backout acd61dc44a39. The changeset prevented closing non-head changesets but did not provide any rationale or test case and I don't see what value it adds. Users might have their reasons to commit something anywhere - and close it immediately. And contrary to the comment that is removed: The topo heads set is _not_ included in the branch heads set of the current branch. It do not include closed topological heads. The change thus prevented closing commits on top of closing commits. A valid usecase for that is to merge closed heads to reduce the number of topological heads. The only existing test coverage for this is the failing double close in test-revset.t. It was added in 3cc2e34d7a7d and seems to not be intentional.

record: ignore trailing content when parsing patches - introduce 'other' lines This makes record work more like import which ignores for instance mail footers in a patch file. This also makes it possible for TortoiseHg to preview unapplied patches containing such footers.

record: abort on malformed patches instead of crashing

localrepo: use "vfs.rename()" instead of "util.rename()" This patch makes "_journalfiles()" return a list of pairs of journal file and corresponded vfs instance instead of a list of journal files in full path, to use "vfs.rename()" instead of "util.rename()" in "aftertrans()". "undofiles()" still returns a list of undo files in full path, because "repair.strip()" expects such list. It'll be also made to return a list of pairs of undo file and corresponded vfs at vfs migration for "repair.strip()" in the near future.

localrepo: use "vfs.setflags()" instead of "util.setflags()"

localrepo: use "vfs.readlink()" instead of "os.readlink()"

localrepo: use "vfs.islink()" instead of "os.path.islink()"

localrepo: use "vfs.rename()" instead of "util.rename()"

localrepo: use "vfs.exists()" instead of "os.path.exists()"

localrepo: use vfs instead of "os.path.*" in sharedpath checking In the point of view of efficiency, "vfs" instance created in this patch should be passed to and reuse in "store.store()" invocation just after patched code block, because "store" object is initialized by vfs created with "self.sharedpath". eBut to focus just on migration from direct file I/O API accessing to vfs, this patch uses created vfs as temporary one. Refactoring around "store.store()" invocation will be done in the future.

vfs: split "expand" into "realpath"/"expandpath" to apply each separately Before this patch, vfs constructor applies both "util.expandpath()" and "os.path.realpath()" on "base" path, if "expand" is True. This patch splits it into "realpath" and "expandpath", to apply each functions separately: this splitting can allow to use vfs also where one of each is not needed.

unionrepo: read-only operations on a union of two localrepos unionrepo is just like bundlerepo without bundles. The implementation is very similar to bundlerepo, but I don't see any obvious way to generalize it. Some most obvious use cases for this would be log and diff across local repos, as a kind of preview of pulls, for instance: $ hg -R union:repo1+repo2 heads $ hg -R union:repo1+repo2 log -r REPO1REV -r REPO2REV $ hg -R union:repo1+repo2 log -r '::REPO1REV-::REPO2REV' $ hg -R union:repo1+repo2 log -r 'ancestor(REPO1REV,REPO2REV)' $ hg -R union:repo1+repo2 diff -r REPO1REV -r REPO2REV This is going to be used in RhodeCode, and Bitbucket already uses something similar. Having a core implementation would be beneficial.

subrepo: fix exception on revert when "all" option is omitted Since fafdff7e9c43, backout does not set opts['all'], which causes KeyError at hgsubrepo.revert.

histedit: update tests for new intervention framework

test-subrepo: add tests for subrepo "storeclean" checks These tests verify that subrepos are not pushed when their store is clean versus a given target repository.

subrepo: do not push mercurial subrepos whose store is clean This patch stops mercurial from pushing unmodified subrepos. An unmodified subrepo is one whose store is "clean" versus a given target subrepo. Note that subrepos may have a clean store versus a target repo but not versus another. This patch handles this scenario by individually keeping track of the state of the store versus all push targets. Tests will be added on the following revision.

subrepo: implement "storeclean" method for mercurial subrepos The mercurial subrepo "storeclean" method works by calculating a "store hash" of the repository state and comparing it to a cached store hash. The store hash is always cached when the repository is cloned from or pushed to a remote repository, but also on pull as long as the repository already had a clean store. If the hashes match the store is "clean" versus the selected repository. Note that this method is currenty unused, but it will be used by a later patch. The store hash is calculated by hashing several key repository files, such as the bookmarks file the phaseroots file and the changelog. Note that the hash comparison is done file by file so that we can exit early if a pair of hashes do not match. Also the hashes are calculated starting with the file that is most likely to be smaller upto the file that is more likely to be larger.

util: add notindexed optional parameter to makedirs function

subrepo: introduce storeclean method Currently this method is unused and it is not implemented for any specific subrepo type (it always returns False). It receives a remote repository path because a repository may have a clean store versus a given repository but not versus another.

subrepo: introduce storeclean helper functions These helper functions are currently unused but will be used to implement the cleanstore method that will be introduced later.

dispatch: exit with status 1 for an InterventionRequired exception (bc)

histedit: switch from util.Abort to util.InterventionRequired where appropriate (bc)

rebase: switch from util.Abort to util.InterventionRequired where appropriate (bc)

dispatch: catch InterventionRequired and print the message with no prefix

error: introduce new InterventionRequired exception Future changes will use this type instead of util.Abort for signalling the user that intervention is required, as in some rebase and histedit aborts.

util: remove unreachable code Found by Cython.

util: remove no-op assignment Found by Cython.

merge more evolve stuff away (what?)

synthrepo: add missing import of sys Found using Cython.

transplant: pass source through to recover

repoview: remove more unreachable code Found using Cython.

merge away some failed evolve fat-fingering

pager: add missing imports of errno and shlex Found using Cython.

largefiles: quiet (and document) undefined name errors (issue3886) These names were found using Cython; I was completely puzzled until I searched the rest of the tree. It's icky to mess with another module's namespace, but ickier yet to do so without a comment :-)

color: add missing import of error Found using Cython.

pvec: use the correct name for an identifier Found using Cython.

repoview: remove unreachable code Found using Cython.

pvec: use the correct name for an identifier Found using Cython.

repoview: remove unreachable code Found using Cython.

mail: add missing import of sys Found using Cython.

statichttprepo: add missing import of os Found using Cython.

worker: add missing import of errno Found using Cython.

histedit: support editing of the first commit (issue3767)

test-commit-amend.t: fix check-code violation from 3a72c89a83ec

util: improve doc for checkcase

scheme: don't crash on invalid URLs

amend: support amending merge changesets (issue3778)