Mercurial on GitHub

An internal presentation on using Mercurial on GitHub.

Transcript

1. Mercurial on
   GitHub
   A crash course introduction
   

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2. Subversion vs. Mercurial
   • Distributed repositories
   • Branches are basically
   clones inside the same
   repository
   • Non-linear history
   • Revision numbers are
   local
   • Commits are offline
   • Moving and renaming
   is tracked
   • Central repository
   • Branches are copies
   inside same directory
   structure
   • Global linear history
   • Revisions numbers are
   sequential and global
   • Commits are online
   • Moving and renaming
   is a combination of
   delete/add
   

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3. Subversion workflow
   • Check out working copy
   o
   • Make changes
   o ...
   o
   • Commit changes
   o "
   • Update copy
   o
   

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4. Mercurial workflow
   • Clone a repository
   o
   • Work, slave!
   o ...
   o " "
   • Pull changes
   o
   o (if pull creates multiple heads)
   • Push changes
   o
   

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5. Mercurial
   • Commits are always local
   • You can push multiple commits at a time
   • Mercurial blocks a push where it would create
   multiple heads in the remote
   o In this case, pull changes, update, merge, commit and push
   

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6. Working with repositories
   organization/repo
   user1/repo user2/repo user3/repo
   user1-local/repo
   pull
   request
   pull/push
   pull pull
   pull
   

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7. History in Mercurial
   head/
   tip
   

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8. History in Mercurial
   head/
   tip
   head
   

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9. History in Mercurial
   –
   head/
   tip
   

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10. Branches in Mercurial
    • Repositories can be treated as branches
    • When pulling, changes commited are added as a
    nameless branch
    • You can switch to a branch by using
    • Merging and commiting preserves current branch
    • To push a non-existant branch to remote, use
    

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11. Pushing changes
    • Always pull and update before pushing
    o –
    o hg merge (if two heads are created)
    o
    o
    • Don‘t push to main repository directly!
    Use Pull Requests.
    

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12. Sharing changes offline
    • You can run a local repository server to share
    changes offline (via )
    o
    • Enables users to pull changes, but cannot push
    

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13. Setting up your
    environment
    • Create SSH key for GitHub:
    o
    o – –
    • create key named
    o
    • Copy the key to GitHub
    • Set up SSH key mapping
    o
    •
    

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14. Set up Mercurial
    •
    •
    •
    o
    –
    • Fork the base repository!
    

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15. Check out source
    •
    •
    •
    o
    

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16. Incoming and outgoing
    changes
    • To preview the incoming changes without pulling:
    o
    • To preview outgoing changes without pushing:
    o
    

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17. Working with GitHub
    • Pull changes from base repository and update
    o
    • Create local changes
    o
    • Commit
    o
    • Verify outgoing changes and push
    o
    o
    • If you‘re ready to push to base repository, create a pull
    request
    

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18. That‘s about it.
    • Go hack.
    

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