Intermediate Git Dr. Roscoe A. Bartlett Sandia National - PowerPoint PPT Presentation

Photos placed in horizontal position with even amount of white space between photos and header Intermediate Git Dr. Roscoe A. Bartlett Sandia National Laboratories Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Overview § Learn git as a data-structure and set of core algorithms to query and manipulate that data-structure. § The git data-structure IS the best conceptual model for git. § This data-structure can be seen in local git repo using: § git log --oneline --graph <ref> § gitk & § Adopting/adapting workflows is easier once you have a basic understanding of the git data-structure and algorithms. § Write personal cheat-sheet and memorize just the basic git commands for your adopted workflows (and Google the rest). § Each project should document commands for adopted workflows (e.g. PETSc and Trilinos). 2

Material Presented § IDEAS Project What-is and How-To Documents (https://ideas- productivity.org/resources/howtos/) § “What is Version Control?” (just mention) § “How to Do Version Control with Git in Your CSE Project” (skim) § Git Tutorial and Reference Collection: § Critical Beginner Git Usage Tips (skim) § Visual Git Reference (in depth) § Visualizing Git Concepts with D3 (git revert, fetch, pull, push, tag) § The Git Object Model (skim) Goal: Present some basics and gain some comfort & familiarity with these sites so that you can go back and complete the learning of the basic git data-structures and core algorithms. 3

The Distributed Git Data-Structure bob Local branch NOT releases topicB replicated in other repos release-2.4 release-2.5 master jc56m p45tg 1800b tracking a47c3 b325c 7ct45 … a47c3 b325c … origin/master remote ‘origin’ remote ‘releases’ remote ‘origin’ origin local Local branch master Reference to refs tracking tracking current branch maint remote branch a47c3 b325c 7ct45 … HEAD releases/ 1800b release-2.4 master Commits tracking • Parts of git graph data-structure are a47c3 b325c c10b9 … replicated across many repo clones. Remote Parent • New parts of graph are added in branch 169a6 origin/master links reference different repos independently. Local branch NOT • Parts of the graph only come together topicA Remote branch tracking remote branch reference when explicitly communicated. • All parts of the distributed replicated Legend: objects are not in ‘local’ repo xxxxx graph may never come together! 4

Summary § Learn git as a data-structure and set of core algorithms to query and manipulate that data-structure. § The git data-structure IS the best conceptual model for git. § This data-structure can be seen in local git repo using: § git log --oneline --graph <ref> § gitk & § Adopting/adapting workflows is easier once you have a basic understanding of the git data-structure and algorithms. § Write personal cheat-sheet and memorize just the basic git commands for your adopted workflows (and Google the rest). § Each project should document commands for adopted workflows (e.g. PETSc and Trilinos). 5