gitCode Version Control

xkcd.com

Casper da Costa-Luis

(ex machine vision dev & resident git-guru @Sony)

PETMR Image Recon PhD Scholar @KCL

casper.dcl@kcl.ac.uk

https://github.com/casperdcl

1

Version ctrl

Track changes for code over time

Revert to older versions easily

Collaborate efficiently

Merge conflicting code reliably

Or at least make it easy to manually do

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Nomenclature

Description git-speak

Project/code database repository

Example of a website

hosting lots of projects

GitHub (https://github.com),

BitBucket (https://bitbucket.org)

Download a project clone

Mark changes to save stage

Save marked files/lines commit (repo <-> list of commits)

Download new changes pull

Fix conflicts [locally] merge (special type of commit)

Upload current state push

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commit

A repository is essentially a list (network) of commits

Commits are permanent checkpoints

Must have a message

xkcd.com7/20

Large Projects have lots of:

Description git-speak

Developers authors

Users/nuisances watchers/stargazers

Code/versions/files commits

Official Versions tagged commits

Bugs/Feature requests issues

Minor spin-offs branches

Major spin-offs

(clone of entire repo)

fork

Suggestions to incorporate

spin-offs

merge/pull request (PR)

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Contributions Strategy

Only one official, stable, up-to-date branch: master

Essentially “latest stable beta version with no known bugs

since last official release version”

Any work-in-progress commits should be in their own

branches

GitHub assigns a unique number to each issue

https://github.com/CCPPETMR/SIRF/issues

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Contributions Strategy

A pull request (PR) is an issue with an associate branch

https://github.com/CCPPETMR/SIRF/pulls

Discussions on issues and PRs are forwarded toCCP-PETMR-DEVEL@jiscmail.ac.uk mailing list daily

Forwarded from github viahttps://groups.google.com/forum/#!forum/ccp-petmr-codebot,which is also a backup in case github dies

We prefer issues to be opened via github

Will never get lost in emails

Track status

Comments/discussion

Cross-reference related issues, PRs, and commits

Mailing list gets notified within 24 hours

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Release Strategyreleasing a new official version

Must be a commit on master branch

Tag the commit using https://semver.org convention

vMajor.minor.patch(-extra)

Major: backward-incompatible

minor: new feature

patch: e.g. fix typo in documentation

v0.9.0-rc2 (Version 0.9.0 Release Candidate 2)

Add release notes

Describe changes since last release

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git cheat sheetgit clone https://github.com/CCPPETMR/SIRF-SuperBuild

cd SIRF-SuperBuild

cmake . && make install

git pull && cmake . && make install # to update

git checkout –b mybranch # create new branch

git add myscript.m other/file.cpp

git commit –m “My cool changes”

git pull origin/master # optional

git push origin mybranch # first time needs an extra `-u`

https://services.github.com/on-demand/downloads/github-git-cheat-sheet.pdf

Thre

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Conflicts and Diffs

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GUIsgit: Git-GUI, gitk, SmartGit

diff: vimdiff, kdiff3, meld

Help a lot with (e.g.)

Avoiding commandline,

Visualising diffs

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