stablerange: fix a bug when a top slice ended on a merge Our "smart" detection of merge was buggy if the top slice ended on a merge. This is not fixed and tested.

slicesrangeat: stop double setting the revsinranges cache The cache should have already been filled by the logic warming the cache for the parent.

subranges: remove the recursivity of the call to isubranges(parentrange) We add some logic to ensure we'll have hot cache for the parent ranges when that matters, the cache is filled from ancestors to descendant to ensure this. The range are still 'created from descendant to ancestors to fill the revsfromrange cache since it important.

subranges: detach cache logic from computation logic Having both the logic around cache checking and setting makes is a bit harder to follow. In addition, this allow to gather the computation logic next to the other related function.

findmissingrange: properly queue new subrange for slicing The previous code was buggy and used the wrong variable leading to no extra slicing being performed to file the sample at the requested size.

findmissingrange: fix reversed value in debug output "oops"

stablecache: warmup on unfiltered repository We only looks at ancestors revision so filtering will not have any effect. This reduce overhead from the filtering.

stablerange: rename the class This is much more than just a cache now.

stablerange: do not inherit from dict This seems like and old cargo cult that when unnoticed.

stablerange: move a utility function around It make more sense to have this small function earlier in the series

stablerange: remove the now unused individual range class That class is now longer necessary, we dropped its usage for performance reason.

stablerange: directly use tuple to refer to a stable range Now that all advance logic lives in the unified class we no longer needs the individual class. Creating and operating on this cache introduce a significant overhead that we can not stop having. From now on, a range a is pair tuple '(headrev, index)'. Long live the tuple.

obshash: properly cache obshash value The code was buggy and only cached non-nullid/non-inherited value. This was previous hidden because we were using a 'propertycache' to cache the value on the range object. This fixes it and restore a lot of performance.

stablerange: directly use 'self' when possible Code movement introduced multiple silly case were we where accessing 'self' though 'repo.stablerange' for no good reasons.

revsfromrange: set the cache for the multiple bottom ranges in merge slicing We no longer rely on the object magic here.

revsfromrange: set the cache for the single bottom range in merge slicing We no longer rely on the object magic here.

revsfromrange: set the cache for the top range in merge slicing We no longer rely on the object magic here.

revsfromrange: remove reference to '_revs' in merge slicing Given '_revs' is a property from the cache, we use the official method of the object we are on instead. That method should be using the same cache than the property if available.

revsfromcache: update cache for the top slice if possible Same logic, we update the cache if have the data.

revsfromrange: skip setting the cache for length-1 top entry The content of the range is trivial to compute.

revsfromrange: update cache for parentrange directly in the code We update it where it matters if we detect that we have the data.

revsfromramge: hard code the single changeset range case That case is trivial and triggering and full stable sort for it seems a bit silly.

stablerange: introduce caching for the full revision in a set Such cache proved handy in the "per-range" class so we carry it along to the unified class. cf documentation for details.

stablerange: add a cache for stablesort ordering This will be very handy for merge, cf inline documentation for details.

stablerange: move revs computation within the main class We still need to compute the revision withing a range when we slice a merge. This is the last large logic that remains in the individual class and we migrate is on the main class.

stablerange: minor method reorders on the main class We put the public method first for clarify.

stablerange: drop "key" and "id" logic form the class We can restrict to the bare minimun for equality and hashing now.

stablerange: drop length from the class There is not remaining user.

stablerange: drop _depth Nothing uses it anymore.

stablerange: drop __repr__ IT was used for debug and the class is on it way out.

stablerange: drop the subranges method on the small class Nobody use it anymore.

stablerange: use subranges from the main class in subrangesclosure This is the last method used on the class.

stablerange: use subranges from the main class in _obshashrange This is the last method used on the class.

stablerange: use subranges from the main class in findrangemissing This is the last method used on the class.

stablerange: make sure nobody use '.depth' anymore

stablerange: use depthrevs in range slicing We stop using the property from the class to get us closer to tuple.

stablerange: use depthrevs in debugstablerange We stop using the property from the class to get us closer to tuple.

stablerange: use rangelength inside the class itself We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in '_slicesatrange' We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in '_slicepoint' We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in subrangesclosure We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in _obshashrange We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in debugstablerange We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: use rangelength in findmissingrange We stop using the building '__len__' this get use closer to be able to use a tuple.

stablerange: make sure nobody use '.index' anymore We rename the attribute for good measure.

stablerange: stop using '.index' inside the class itself We now access '[1]' as we'll do with the future tuple.

stablerange: stop using '.index' in '_slicesrangeat' We now access '[1]' as we'll do with the future tuple.

stablerange: stop using '.index' in '_slicepoint' We now access '[1]' as we'll do with the future tuple.

stablerange: stop using '.index' in 'rangelength' We now access '[1]' as we'll do with the future tuple.

stablerange: stop using '.index' in '_queryrange' We now access '[1]' as we'll do with the future tuple.

stablerange: stop using '.index' in debugstablerange We now access '[1]' as we'll do with the future tuple.

stablerange: make sure nobody use the 'stablekey' property outside the class

stablerange: make sure nobody use '.head' anymore We rename the attribute for good measure.

stablerange: stop using '.head' inside the class We now access '[0]' as we'll do with the future tuple.

stablerange: stop using '.head' in '_slicesrangeat' We now access '[0]' as we'll do with the future tuple.

stablerange: stop using '.head' in '_slicepoint' We now access '[0]' as we'll do with the future tuple.

stablerange: stop using '.head' in rangelength We now access '[0]' as we'll do with the future tuple.

stablerange: stop using '.head' in debugstablerange We now access '[0]' as we'll do with the future tuple.

stablerange: remove node unused 'node' property Close to killing that object.

stablerange: stop using '.node' in __repr__ This remove the last user to this method.

stablerange: change the key to use the revision number Using node is more stable but for now do not have on disk caching and revision number should be find in memory. This makes the data used for the file cache closer to what it will be when we use tuple. We might reintroduce node in the future but let us keep it simple for now.

stablerange: stop using '.node' in _queryrange We access the range-head revision number by index and convert it on site.

stablerange: stop using '.node' in debugstablerange We access the range-head revision number by index and convert it on site.

stablerange: stop using '.node' in findmissingrange We access the range-head revision number by index and convert it on site.

stablerange: stop using '.node' in obshashrange We access the range-head revision number by index and convert it on site.

stablerange: stop using '.node' in subrangesclosure We access the range-head revision number by index and convert it on site.

stablerange: have the class behave as a tuple If we want people to use a tuple, we should offer them a tuple. This should help update most of the code iteratively.

obshashrange: extract computation back into the discovery module This obshash is related to discovery and it seems more appropriate to have to live there. This remove the last large piece of logic from the class. We'll now be able to slowly turn it into a tuple.

obshashrange: use a small utility function to access the obshash If we want the object to disappear we needs the top level code to stop accessing its attribute.

debugstablerange: minor code reformat The content of that list will become more complex as we drop the object so we make sure to have one value per line for clarity.

stablerange: move the subrangesclosure inside the module This seems more suitable and open the way to simple update of how we build things without too much impact outside the module. The debug command is still in the 'obsdiscovery' module because it also deal to obshash and I'm not sure of were this should live yet.

stablerange: compute subranges from parent when possible Unless we are a merge, we can infer the standard subranges of a range by reusing the subranger of its parent. We update the implementation to do so. We still needs the "old way" for merge. We move that code in a dedicated function for the sake of simplicity.

stablerange: add an official warmup function The function is responsible for making sure we have the necessary data for a sets of heads. For now this only warm the depth cache. More will follow soon. Such explicite warmup will be usefull for on disck caching as an early point of writing will be easier.

stablerange: remove now unnecessary setter The class is handling all computations and cache access by itself now. So we can drop this method.

stablerange: directly perform slicing in the getting method Now that all necessary functions are available, we simply apply the standard slicing on cache miss and proceed.

stablerange: move standard slice point definition in main class More migration of code away from the doomed individual class.

stablerange: move the slicing method on the central class We migrate code away for the individual range class.

stablerange: move the range class in the new module Our ultimate goal is to remove this class for performance reason. however for now, it contains most of the code we care about so we migrate it as a block first.

stablesort: move into the stablerange module The stable range rely on the stable sort so it make senses to move it there. Will need direct access to it in the future.

subranges: migrate handling of single element range This is the simplest case by far, so we start with that one. We still use the rich object as an argument, but we'll do our best to not relying on that. This is important for performance reason.

stablerange: move the subrange cache into our new class This is the first step toward having more logic in that class

depth: extract code dedicated to depth of a merge in its own function The merge case is more complicated than the regular one, we extract is for the sake of clarity.

stablerange: move 'depth' inside a new 'stablerange' module The stablerange used for discovery requires significant amount of code. There is algorithme, cache, cache persistence, etc. So we create a dedicated module for it. The function is directly moved into a rich class handling cache (for now in memory) because we know we will need it.

obsdiscovery: document the status of the module I figured i would be useful to document what we expect from the code in each module.

split: move the debugcommand into a dedicated module The code related to debugobsstorestat is fairly independant, we move it into its own module.

legacy: move 'debugrecordpruneparents' in the extensions The transition is a couple of year old now, repository with the old format must be quite hard to find by now.

checks: correct the shebang line filtering for python files As it is, the only related file is docs/test2rst.py, which was covered by **.py. Not sure if it matters, but most patterns in core tests are for "#!.*?python". (Though there are a couple "#!.*python" tests.)

tests: add glob for Windows

tests: adds simple test case for heads checking This is the start of some systemic testing of the head superceeding detection mechanism.

tests: move exchange utility in testlib We have a testlib directory now lets use it.

exchange: fix some wrong reference to serveronly The function have all moved into 'obsexchange' now, so we do not need (and actually cannot) seek them in 'evolve.serveronly'.

checks: add a test that check MANIFEST.in content This make sure we keep the things updated.

README: add a link to mercurial devel This will help people to find the mailing list details.

README: tries to improve the title about server only This seems a bit better.

README: remove mention of make Using pip in all cases seems a better direction.

version: mark the current source as development version for 6.0.0 This is useful to distinguish the development version from the latest tagged version. In this particular case, this will allow us to publish a pre-version on pypi.

mercurial-3.8: merge with future evolve-6.0.0 We introduces the new code on the compat branch to check the tests.

mercurial-3.9: merge with hg-4.0 branch We merge with the code for the future evolve 6.0.0 code to check for compatibility. Only minor test output change (" -> ') have been noted.

mercurial-4.0: merge with future 6.0.0 A new version will be released soon, we start handling mismatch in test output to make the actual release time smoother.

checks: update pyflakes matching too We make sure to not select removed files.

checks: do not run pyflake on removed file The fileset matches removed files. This confuses pyflakes for good reasons.

compat: closing mercurial-3.7 compatibility branch The "evolve-6.0.0" release drop compatibility with Mercurial 3.7. No new commit are expected on this branch.

compat: closing mercurial-3.6 compatibility branch The "evolve-6.0.0" release drop compatibility with Mercurial 3.6. No new commit are expected on this branch.

compat: closing mercurial-3.4 compatibility branch The "evolve-6.0.0" release drop compatibility with Mercurial 3.4. No new commit are expected on this branch.

compat: closing mercurial-3.5 compatibility branch The "evolve-6.0.0" release drop compatibility with mercurial 3.5. No new commit are expected on this branch.

README: timeless typo fixes This applies some feedback timeless provided me from IRC.

cleanup: drop an empty section header

compat: drop some <hg-3.4 compatibility code The `hg commit` commands has a -i flag for ages now.

README: more update to prepare for pypi upload * mention the evolve.serveronly extension, * remove help related to topic into a different README file.

evolve: update the capabilities and commands name for obshashrange We makes is clear that these version are useful for earlier testing but they are not ready for any kind of real usage yet.

README: more change to have a pretty rendering on pypi We moves section around and fixes some markup.

MANIFEST.in: fix various mismatch check-manifest is no longer complaining

README: rework install instruction For both evolve and topic. The topic introduction is updated too.

README: rework the intro Less scary wording (similar to the wiki changes) and point to the user mailing list.

rangeobshash: minor cleanup of the obshash code We achieved minor speedup by delaying the hashing until we know it is needed.

stablerange: remove call to 'repo.revs' It turned out that the percentage of time spend parsing the revset string was two digits, so we compute de heads inline.

stablerange: reuse node calculation as much as possible We have a property cache with that value, so we just reuse it.

stablerange: adds some caching of the subranges The goal of subranges is to be as reusable as possible, so we cache the subrange relationship to take advantage of this.

stablerange: operate on an unfiltered repository We only do operation on ancestors so using unfiltered is fine.

depth: use lower lever function to compute missing The time spend parsing the revset is noticeable.

depth: update depth to code to reuse ancestors depth Computing the depth of all N revs is no longer 'O(N**2)'

obsdiscovery: extract a smarted depth in utility The function is reusing previous depth for ancestors unless this is a merge.

obsdiscovery: simply some of the missing computation

discovery: implement some range based discovery This use the previously implemented methods to implement some discovery and fetch method using ranges. There is currently major performance issue and some aspect of the protocol will changes.

discovery: introduce a official 'obshash associated to a range The hash in a combination of the hash a its subrange. If the range is a leaf, we have the obsmarker relevant to the node in that leaf range.

discovery: introduce "stable slicing" methods We introduce new code that leverage the stable sorting to slices a graph in a way "stable" accross repository. This should allow us to use theses slices for obsolescence markers discovery.

discovery: adds a function doing revnum independant sorting The function is doing a topological sort without depending on revision number. This make the sort independent of the repository and suitable for discovery.

hgignore: also ignore the 'dist' directory This is generated by the 'sdist' command

obsexchange: drop unused module shame shame shame

MANIFEST.in: also includes topic That was also overlooked when we added topic.

MANIFEST.in: fix to include all evolve submodule This was overlooked before.

obsdiscovery: organize the code by category A private function get promoted to public since another module uses it.

evolution: drop the old __temporary__.advertiseobsolete option Mercurial code supports such feature directly though its 'experimental.evolution' config option. So we drop the old code and config.

README: mention the 'serveronly' extensions It is now properly installed with the package.

server only: test a more standard method of disabling exchange We have an "official" config option from core so lets just use it.

debian: don't delete evolve and topic extensions The debian packaging rules deletes all __init__.py to avoid conflicting with the __init__.py that declares the namespace package. Now that the evolve and topic extensions also live in __init__.py files, we clearly don't want to delete all __init__.py files anymore; only the hgext3rd/__init__.py should be deleted.

serveronly: replace exc.message with str(exc) BaseException.message is deprecated in Python 2.6, so use str() instead.

cleanup: stop using 'repo.join' methods These repository method might get deprecated soon. In addition, accessing the vfs-s is not that hard.

setup: add author_email The 'sdist' command complains about it otherwise.

readme: make it valid rst That will eventually please pypi

setup.py: remove unused and harmful code importing mercurial This was failing on some build system we have. The import seemed to succeed, but then mercurial.__all__ would fail. I don't know why, but since it's unused anyway, let's just drop it.

docs: update references to installation path

test: rename serveronly tests to reflect the new extension name

evolve: stop running 'serveronly' setup Since there is no common logic remaining the smaller extension we can stop running its setup in the main extensions

discovery: directly merge the 'obsdiscovery' exthelper in top level extensions There is no reason to proxy it through the 'obsexchange' submodule.

compat: drop advertising of unsupported experimental bundle2 part The support for this part was dropped long ago in 74bc8a0c2c02. But we forgot to remove it from the 'simple4server' extension.

exchange: dispatch all code in 'serveronly' to the appropriate submodule All code related to exchange is now in either 'evolve.obsexchange' or 'evolve.obsdiscovery', and the 'serveronly' extension is using their 'exthelper' to set itself up. As a side effect, the 'serveronly' extensions now enable better exchange when pushing from that server too.

capabilities: properly sort capabilities after updating them Capabilities are usually sorted. This is especially useful to avoid silly error in test.

pull: also issue warning for old mercurial version

exchange: split between modern and legacy code We make it clearer what code is old crust and what code is the cutting edge part.

push: add extra warning about pushing to old server Pushing using old method is slow and racy. We adds warning to point this to the user. We also add inline comment to clarify the function purpose.

push: exit obsexchange early if disabled We were exiting the function later, in particular -after- issuing a message about exchanging obsmarkers.

compat: drop special code handling change in push/pull op API All version of Mercurial we support have the same API.

discovery: split discovery related code in 'obsdiscovery' More code splitting for more clarity.

exchange: rename the module Let's add a 'obs' prefix to make the module role clearer.

setup.py: include all evolve submodule We are splitting more and more code into submodule, we make sure their are properly installed. As a side effect the 'legacy' module is now installed, that is not too important. The 'evolve.hack' package is still non installed by default, as intended.

evolve: switch away from deprecated repo.opener

serveronly: use the same extensions metadata than evolve This will avoid them to drift out of sync with evolve.

evolve: move extension metadata in their own module This will allow the server only extension to reuse them. As a side effect we can now simplify the config parsing in setup.py

evolve: specify the 'minimalhgversion' 3.7 added a new nice and shinny variable to help user know when they use the wrong version of Mercurial with an extension. We now use it.

serveronly: give the sub extension a way to access to the 'evolve' module We keep it as clean as possible but if the extension is specified with a direct path, we have to be a bit hacky. Being able to access the whole evolve extension from the 'serveronly' extension will lift multiple constraints on how we organise the code and will allow for cleaner and clearer code. We extract a minor function into a 'utility' module to have something to depends on.

test: update test to check for various way to import the serveronly things We add a "setup script" that update the PYTHONPATH to allow direct import of the extension code. Then we tests that all way to import the extensions works.

tests: move "test setup" script into a 'testlib' directory This will avoid cluttering the tests directory.

exchange: move code related to exchange into a 'evolve.exchange' submodule The evolve extension is HUGE, we split exchange code appart before doing more work on it.

exthelper: move command declaration into the exthelper This is necessary to allow sub module to declare commands too.

exthelper: add a 'merge' method This will help us spread more code in different sub module.

exthelper: extract into its own submodule That code is fairly independant, we extract it into its own extensions to clarify the code

makefile: add an 'install-home' target It is similar to the Mercurial one.

makefile: only check for HGROOT when running tests Otherwise we breaks other target that do not needs HGROOT.

tests: split pyflake and flake8 tests This allow more parallelism and better skip message

flake8: run on all python file We can now run it on all file in the repository to catch potential regression.

flake8: fix error in 'setup.py' Some strange indentation in there.

flake8: fix error in 'test2rst.py' There is variosu dead code in there :-/ but we just fix flake8 complains for now.

flake8: remove "error" in documentation configuration The "error" are debatable but cheap to fix.

flake8: enable on evolve too Now that all error are fixed we can run it on all file to prevent regression.

flake8: update the code sources to fixes a horde of pyflake warnings There is many of them, they all fixed.

flake8: register 'xrange' as a builtins For some reason, flake8 thinks is is undefined.

flake8: ignore an addition rules related to import Our initialization code is too complex to make flake8 happy

flake8: document all the exception we added

README: mention the addition of the topic extensions That is probably worth noting.

tests: run pyflake on all python files We have fixed the handfull of error pyflakes found on evolve so we can setup the test to prevent regression. Next stop flake8.

serveronly: fix undefined variable This is a legit bug caught by pyflake

legacy: properly test for mercurial version in the legacy extensions Otherwise 'demandimport' would delay the raising of ImportError.

evolve: prevent global variable shadowing Small and harmless pyflake complains.

evolve: drop some unused variables More pyflakes catches.

evolve: drop some unused import topic came with pyflake checking, let us make use of it.

README: fix evolve installation path We forgot to do so when we moved things to hgext3rd.

topic: merge the topic extension in the evolve repository There is a lot of synergy between the two concepts. Topic is expected to be able to smooth multiple of evolution sharp edge. Having them both in the same repository will make this collaboration easier.

test: adapt to new core output Troubles are now displayed by log so we have to update the test.

test: adapt to change in mercurial output Nothing major here.

compat: handle difference of signature for update destination hooks The 'check' argument have been dropped in 11c253997b0e. So we make it optional for compatibility.

setup.py: also install 'hgext3rd/__init__.py' This file is needed for the namespace package to work. (And also for the package to work on its own at all).

tutorial: add a very basic pointer in the readme Ideally we should at least build the html from the rst.

tutorial: add a second part about having multiple topic

tutorial: add a first version of the tutorial with the basics This is probably not wonderful but at least we have a base.

doc: add more details about the head checking Once again, probably not great, but better than nothing.

documentation: some basic update of the documentation So far the documentation was pretty scarce and a lot of important information was missing. The new content is probably not great but it is an improvement.

flake8: ignore N801 N801 is "class names should use CapWords convention" The message comes from a pep8 plugin "pep8-naming" which cares about naming conventions. If the plugin is installed, it is automatically used by pep8 and flake8.

flake8: don't ignore E713 now that it's fixed E713 is "test for membership should be ‘not in’"

flake8: fix E713 style

flake8: fix E301 style

flake8: fix E111 style OFF BY ONE ERRORS ARE THE WORST

flake8: fix E222 style

flake8: fix E127 style

flake8: fix W391 style

tests: add flake8 check This test will hopefully help prevent style errors. To be determined: which errors / warnings to ignore?

flake8: add file for rules to ignore This will help prevent users that have an editor with flake8 capabilities from fixing linter errors for rules that are not wanted by the project. Initially, this ignore list includes everything in the project that violates pep8. I'll try to ween this list down to something a little more manageable.

init: guard _namemap with repo.topics (issue5351) This prevents reading extra data on all repo commits when there is no topic for a given name. _namemap is called a lot, and it is often called for commit shas -- which should pretty much never be names of topics...

init: cache repo.topics

stack: add warning about multiple heads This seems a good spot to nudge people toward reducing there head count.

stack: add some behind information This is the next useful thing after branch

stack: add some basic branch information In the same spirit as knowing the topic you are on, having some branch data seem useful (yet, this smell a bit like summary)

stack: add some header with the topic name This is the first step of a move to add more data about a stack in the command output.

test: add testing of stack output in 'stack-data' test. We are going to display common information, so we reuse test case.

test: rename 'list' test to 'stack-data' We are about to add stack data information to 'hg stack'. As we'll re-use the test data creating the 'test-topic-list.t' we need to rename it first to embrace its new semantic.

stack: also dim bases Now that they may have index it seems better to have a stronger marking for bases.

stack: reusing the index number in base when applicable This clarify the branching when it is easy to track back the branching point. This does not takes the evolution graph into account yet.

stack: extra argument validation logic outside of showstack It seems sensible keep the 'showstack' function purely about actually displaying and existing stack.

summary: properly label the topic name in summary This should be labelled 'topic.active' so that color can pick it up properly.

topic: list the branches this topic belong to when verbose Using the verbose listing a bit more, this seems to be useful information.

topic: properly justify the verbose data when listing topic We align all data to the widest topic.

ngtip: rely on topicmap for 'ngtip' ngtip is an old function that predates the introduction of a more proper topic aware 'topicmap'. We replace the old code with a call to the new one. This change set function return type and have minor effect in a couple of place.

topic: list the number of 'behind' changeset when --verbose is used Displaying more information in the topic list is useful, we continue with the number of 'behind' changesets. This 'behind' count the number of new changesets on the default rebase destination. This will highlight topics that need rebasing.

destination: honor the sourceset argument of _destmerge Mercurial gained a "sourceset" argument to compute the merge destination of any changeset (the one in the 'sourceset'). This now works for the version in topic too. The support is quite basic (because we pick only one changeset from the sourceset) but that's a start.

destmerge: improve topic head computation and handling This rework get use two benefits: - heads are now computed on a "stabilized" state, - heads above the 'source' are now properly cleaned up,

evolve: extract the code copied from evolve in a submodule This will allow us to use that code in other module.

destmerge: honor the 'onheadcheck' argument This argument was introduced in Mercurial some time ago but the topic extension was never updated to take it in account. This is now fixed.

destination: use the correct abort class for error These errors have been in Mercurial long enough. Having them will make the coming changesets simpler.

topic: list the number of head when --verbose is used Displaying more information in the topic list is useful, we continue with the number of heads on the topics, this will help highlight the problem to users. We only display head if there is more than one.

topic: list the number of troubled changesets when --verbose is used Displaying more information in the topic list is useful, we continue with the number of troubled changesets. This will help people to spot topics that needs evolution, for example after a pull.

topic: list the number of changesets when --verbose is used Displaying more information in the topic list is useful, we start with the most obvious: number of non-obsolete changeset in the topic.

topic: add color for the active topic We reuse the same color that the one used for the active bookmark.

topic: add formatter support Using formatter to output the list of topic will add support for color and richer templater. We add some test for output control. We introduce a dedicated test to help with coming more complexe output.

topic: extract the code listing all topics The code will become more complexe with formatter support and additional data in the verbose output. We extract the code in its own function first.

stack: introduce and explicite command to display the stack If is worth testing having the feature lives outside 'hg topic --list'. The 'stack' name is sub optimal because the conflict with 'status'. using "hg st" would still work as 'st' is hard coded, but this mean 'hg stack' has no short version.

testedwith: update to 3.9 This is might still 3.7 compatible but I'm no longer running the test and I would says the user base is small enough to not care.

topic: make sure we have the 'wlock' when setting topic We where writing the '.hg/topic' file without a lot. That was bad.

cleanup: removed unused mercurial.util import

compat: tolerate missing rebase extension

compat: mercurial dropped alias for hashlib.sha1

destination: add an XXX about handling destspace in destmerge This that we hopefully do not forget about this.

update: calculate 'partial' as core does

discovery: flake8

destination: flake8

style: update __init__.py

compat: adapt to the new destspace argument of destmerge The argument is currently ignored in the topic case for simplicity, but we properly accept it and propagate it to the original function to prevent crash and behavior regression in the non-topic case.

stack: prevent crash when topic is rooted on nullid We exclude null from displayed base. This was causing a crash when trying to display its description (we'll still have to handle the empty description case, but it is now less urgent).

test: add topic on the first 2 changesets too This will be used to add a test for topic rooted on nullid. We introduce this in its own changeset to reduce the noise if the actual changeset.

test: remove comment about new head warning The new head warning was buggy. This was fixed in bdc5bb223b50.

stack: also change the indexing of the t# reference Changeset 61f36480740f changed the index displayed (we now index from 1), but forgot to update the logic used to resolve the 't#' name. This changeset fixes it.

stack: change the ascii symbold for base Now that the children line go upward, '_' is no longer clear as is take the lower part of the line. We go for '^' that use the upper part.

stack: reverse the display order Most mercurial command display the most recent changeset first. We put `hg topic --list` inline with this.

topic: extract display from entry computation We are about to reverse the order of the output (most recent first) so it will be useful.

stack: start indexing at 't1' instead of 't0' I think 't0' could have special meaning (eg: before 't1', but still with topic activated) so let's keep room for that. Indexing from 1 is not crazy anyway.

commit: wrap "commitstatus" to take topic into account The "created new head" message was appearing for every single commit made on a topic. It should now properly only appears when a new head is actually created on a topic.

uisetup: add call to 'topicmap.modsetup' this was forgotten in 99c1a26abf3f. Tests did not broke because the wrapping of cg.apply only have performance impact (cache warmup).