When I was your age we used RCS and SCCS, in the snow, up hill, in both directions. :)
Seriously, I have no doubt git has an awesome on-disk format, but whenever I use the git(1) command I want to slit my wrists. I'm sure if a developer uses it many times a day it's possible to get used to it, but as a sysadmin that only uses it sporadically, I basically do:
* git clone
* vi repo/some/file/blah
* git add/commit/push
* rm -rf repo/
What do you find difficult about it?
For the little while that I sometimes used Hg I found it much easier to get my head around.
It's mostly a lack of practice/use.
Shared windows mount
Visual Source Safe
CVS
SVN
Perforce
ClearCase
Git
Team Foundation Server
Of those I still use Git and SVN. Aside from the shared network drive, VSS and ClearCase are in a dead heat for the worst SCM I have been exposed to.They called it "multiple checkout", and the manual strongly recommended you do not turn it on.
The software had issues with corruption due to operations not being atomic.
It was literally less functional than copying to a shared drive. Of course management and other developers refused to believe that OSS solutions were better, MS ecosystem developers were an extremely insular group.
Incidentally, I remember one person at Microsoft who claimed to be involved in the decision to adopt sd circa 1999 saying that Microsoft has the right to turn sd into a product if it so chooses. (He/she was responding to contrary claims made on an internal email mailing list which was very widely read, so I assume if he/she was misremembering or lying he/she would have been called out.) Though ultimately MSFT made VSTS/TFS version control instead, which has striking resemblances in concepts to sd/p4.
dunno, I like git better, but at the time it did what our small team needed. Granted, we always ran into issues with one of us having a file locked that someone else needed, but onboarding was a breeze.
I'm glad I use git now, but Sourcesafe was an okay introductory source control solution.
Watching hg and git grow up and compete as a darcs user was fascinating. Neither hg nor git had the elegance of the darcs UI (and arguably never will due to disparities in the underlying distributed code model), but it was clear from very early on that both hg and git were beating darcs on performance for large, active repositories. (Which was never a problem for a college student working on teams of maybe 1 to 3, but obviously a hard recommendation for the real world.) I experimented some with hg at the time because it had good Windows support, but had no reason to switch from darcs in college.
My first couple of jobs after college had me spending a lot of time in TFVC, and that eventually that lead to a much greater appreciation of git (and pushing teams to migrate from TFVC to git), and by that point TFS had already starting supporting git side-by-side TFVC, though ironically those same teams pushed hard for GitHub Enterprise. (Which does seem to underscore that git and GitHub really were so co-beneficial.)
By that point a lot of what hg had done right the git team was starting to pick up. At the very least, we should remember hg for pushing git to be better.
(As one example, someone else pointed to `git stash` as something that they didn't think hg had, but as I recall `mercurial queues` [MQ] was one of the earliest hg plugins, and MQ influenced the designs of both `git rebase` and `git stash`, and MQ itself was mostly deprecated by `hg rebase` and `hg shelve` which learned a lot from MQ.)
I believe those have been deprecated in favor of the evolve extension.
Mercurial is my goto for version control. However, in my experience, the information on the ideal tools/extensions is very scattered. The Mercurial book is 10 years old! For example, few mercurial users make use of branches for throwaway work - they use bookmarks. But how is a new user supposed to know that?
All the documentation I spotted currently still lists evolve as "experimental", and that doesn't help with any confidence of which tools/extensions to use in day-to-day operations, on top of how scattered the documentation is. It is interesting, perhaps how hg has a better UI, but git has always had arguably more consistent documentation.
(Similar too, both hg and git are built as sets of "plugins" to the core CLI but hg requires much more explicit installation and git just bundled a lot of them directly together and implicitly runs anything that even looks close [any script in the PATH that fits git-command may be run for git command], making it less clear which hg commands to use despite the better general UI, and easier to get started in git with a smorgasbord of commands.)
I somewhat remember the Named Branches versus Bookmarks discussion/confusion thing from the last time I attempted to use hg. It sounds unfortunate that it still doesn't seem very well documented or well explained this many years later.
I believe it is bug free, and fit for real world usage, and has been for years. If you read the details, the issue is there is a chance for performance degradation, and they consider that as "backward incompatible".
I'm sure it's changed now, but the lack of cheap fast branching was jarring.
I think many UI fetishists forget: Good UI helps begginer adoption but has to be incredibly way better to drive any readoption. But professionals will often have to suck it up and use a shitty UI if it means solving a technical shortcoming better.
In my earlier team at fortune 100 firm, most developers use Windows with svn. We tried git and it did not work well due to UI and windows support. They were able to pick up UI easily and were quickly productive in mercurial. It worked pretty good on all 3 platform Windows, Mac and Linux. I am talking of time when GitHub was not that popular in corporate world.
Performance was never an issue.
Also at that time mercurial followed philosophy of being explicit and every merge needs to be explicit and committed with immutable history. So can see the evolution of code along with the mistakes made.
I believe the success of git is due to GitHub and for many it's synonymous.