Difference between revisions of "Darcs vs. Git"
Jump to navigation
Jump to search
(push, pull, branch) |
(Added context for GHC's switch from darcs to git) |
||
| (14 intermediate revisions by 4 users not shown) | |||
| Line 1: | Line 1: | ||
| + | = Darcs Resources = |
||
| − | I don't understand why so many people move from darcs to git. |
||
| − | + | * http://darcs.net/ Main site |
|
| + | * http://darcs.net/FAQ |
||
| − | Darcs can replace identifiers, Git cannot. |
||
| − | I often rename identifiers. |
||
| − | The identifier substitution of Darcs both saves space |
||
| − | and allows for smooth merging. |
||
| − | In Git renamings of identifiers look like you alter a lot of lines here and there. |
||
| − | I don't think that Git can easily implement that feature, |
||
| − | because it has no notion of a patch. |
||
| + | * http://www.haskell.org/haskellwiki/Darcs |
||
| − | == darcs check --test == |
||
| + | * http://en.wikibooks.org/wiki/Understanding_Darcs/Patch_theory_and_conflicts |
||
| − | Darcs lets you easily run a test suite after every commit. |
||
| − | Usually I register |
||
| + | = Git resources = |
||
| − | : <code>cabal configure && cabal build && cabal haddock && cabal test</code> |
||
| + | * http://git-scm.com/ Main site |
||
| − | as a darcs test. |
||
| − | After recording a patch, |
||
| − | darcs unpacks the repository temporarily in the state after adding the patch. |
||
| − | Then it runs the test suite within that temporary copy of the repository. |
||
| − | If you add a file the Cabal description but forgot <code>darcs add</code> |
||
| − | or vice versa, then the darcs test will quickly spot the problem. |
||
| + | * http://git-scm.com/book |
||
| − | This almost not possible with Git. |
||
| − | It could certainly be hacked into <code>.git/hooks/pre-commit.sample</code>, |
||
| − | but the crucial feature of running a test |
||
| − | is to reject a commit if it does not pass the tests. |
||
| − | If there is a way in Git then it is by far more complicated than in Darcs. |
||
| + | * http://gitref.org/ |
||
| − | I see no reason why Git does not support pre-commit tests properly. |
||
| + | * http://bramcohen.livejournal.com/74462.html |
||
| − | == Pushing to the wrong repository == |
||
| − | + | = GHC's switch from darcs to git = |
|
| − | to an unrelated repository or to the wrong branch of a repository. |
||
| − | And it is cumbersome and dangerous to get rid of the wrongly pushed commits, |
||
| − | if operating in a bare remote git repository. |
||
| − | In a bare git repository you cannot use commands like 'git branch' |
||
| − | that you are familiar with in a working copy. |
||
| − | In darcs this cannot happen so easily |
||
| − | since normally darcs asks you which patch to push. |
||
| − | This way you can see early if something gets wrong. |
||
| + | * http://www.haskell.org/pipermail/glasgow-haskell-users/2011-January/019752.html |
||
| − | == Pushing to repositories with working files == |
||
| + | * http://www.reddit.com/r/haskell/comments/ezgvs/rfc_migrating_ghc_development_to_git/ interesting thread |
||
| − | Pushing to a bare Git repository requires that you enable |
||
| − | the <code>post-update</code> hook. Why? |
||
| − | Pushing to a Git repository with working files is even more cumbersome. |
||
| − | I like to point people to certain files in a remote repository, |
||
| − | e.g. by an HTTP URL. |
||
| − | This requires automatic updates of working copy files when pushing to the remote repository. |
||
| − | If you try to push to a Git repository with working files |
||
| − | that is not prepared for this action |
||
| − | then you get a message that it is not possible |
||
| − | and what alternatives you have. |
||
| − | Among the alternatives there does not seem to be one |
||
| − | that automatically updates working copy files after a push. |
||
| − | Maybe it is possible in Git, but it requires at least some effort. |
||
| − | |||
| − | In darcs there is no distinction between bare repositories and working copies. |
||
| − | Working files are always automatically updated. |
||
| − | |||
| − | == Pull and stash == |
||
| − | |||
| − | I often have locally modified files when pulling patches from somewhere else. |
||
| − | With git this needs at least three steps: |
||
| − | <code> |
||
| − | git stash |
||
| − | git pull |
||
| − | git stash pop |
||
| − | </code> |
||
| − | With darcs it is just <code>darcs pull</code>. |
||
| − | Git does not make backup files if there is a merge conflict, Darcs does. |
||
| − | |||
| − | == Branches == |
||
| − | |||
| − | When working with Darcs I missed branches. |
||
| − | I thought it would be a good idea |
||
| − | to let the versioning system manage my attempts to solve hard problems in my projects. |
||
| − | I expected that if people clone my repository or pull patches |
||
| − | that they access all branches of my repository simultaneously. |
||
| − | I hoped that native support for branches |
||
| − | would be better than creating a new working copy for every branch. |
||
| − | |||
| − | Maybe Git got branching wrong |
||
| − | but today I am uncertain whether there is a good way to support branching |
||
| − | other than not supporting branching. |
||
| − | Git does not handle all branches of a repository simultaneously. |
||
| − | Git can push and pull commits from one local branch to another remote branch and back. |
||
| − | |||
| − | It is not so simple in Git to switch a branch if there are local modifications. |
||
| − | You need to <code>git stash</code>. |
||
| − | And what about the open text editor |
||
| − | that contains a file that gets modified by switching a branch? |
||
| − | Sure, modern text editors warn about changes on the file storage |
||
| − | but it is still easy to accidentally overwrite a file on one branch |
||
| − | with the contents of that file on another branch. |
||
| − | |||
| − | What I actually ended up is to create one Git working copy for every branch. |
||
| − | This way, switching between branches is easy. |
||
| − | This is precisely the way I work with Darcs. |
||
| − | |||
| − | |||
| − | == GitHub == |
||
| − | |||
| − | github sucks, looping scripts, pull requests, how to get a git repository |
||
| − | |||
| − | |||
| − | == Merging == |
||
Latest revision as of 18:50, 18 June 2014
Darcs Resources
- http://darcs.net/ Main site
Git resources
- http://git-scm.com/ Main site