1. With Mercurial and Progress

2.   Introduction  What is version control ?  Why use version control ?  Centralised vs. Distributed  Why Mercurial ?  Using Mercurial [with Progress]  Examples / Demos  Questions Overview

3.   Julian Lyndon-Smith, dot.r limited  Progress developer since v3  Fan of vcs since 1987  Developed, sold Boss (Progress-based vcs)  Other vcs systems used include  Roundtable ~1992-1994  SourceSafe ~1994-1998  Cvs ~1998-2004  Subversion ~2004-2011 Introduction

4.   As developers, we write code that changes over time  Bugs  aka “feature”  aka “undocumented behaviour”  aka “works on my machine”  New functionality  Aka “we could charge for this”  Better way of doing something  aka “I want to play with this cool new tech” What is version control?

5.   Everyone uses a version control system  Just not the right one  Copy foo.p foo.[x].p (where x=1 to … )  Modify foo.p What is version control?

6.   Audit trail of changes  Who did what, where, why and when ?  Syncronization  Share the same code between developers  Backup  Get any version of the file from any time  Revert  Throw away local changes Why use version control?

7.  Centralised vcs checkout checkin checkout checkin checkout

8.  Centralised vcs  Centralized version control systems  Cvs  Source safe  Rcs  Subversion  Single central copy of project / source (aka “repo”)  Committing records changes into central repo  Other developers see this change

9.  Centralised vcs  Workflow  Pull changes from central repo  Make changes  Commit changes back to central repo  Disadvantages  Only “latest” copy of source available  Need to be online / connected  All changes to a file have to be in one changeset

10.  Strengths  Workflow is familiar to most developers  Only one place for all source  Trunk has latest version

11.  Weaknesses  Poor merging  No offline commits  Any commit is available to all users  Working or not  Breaks build servers  Days or weeks between checkins  Commits only apply to selected subdirectory and children (subversion)

12.  Distributed vcs checkout checkin checkout checkin checkout checkin checkout QA RepoBuild Repo

13.  Distributed vcs  Distributed version control systems  Mercurial  Git  Arcs  Bazaar  Multiple copies of all versions of project / source  Committing records changes into local repo  Other developers do not see this change  Until pushed back to remote repo

14.  Distributed vcs  Workflow  Clone repo  Make changes  Commit changes back to own repo  Push changes up to remote repo  Disadvantages  None …

15.  Strengths  All repositories are equal  Offline history  Offline commit  Less chance of merge conflicts  “hidden” experimental branches

16.  Weaknesses  Who has the “latest” version ?  Large Binary files  Fixed in later releases  Mindset

17.  Why mercurial ?  Boiled down to git or mercurial  Git  Poor documentation  Complicated command lines  Gui for eclipse did not work for me  Mercurial  Worked first time  Gui worked first time  Purely personal choice.

18.  Using mercurial  The basics

19.  Using mercurial  Download from http://http://mercurial.selenic.com/ http://http://mercurial.selenic.com/  Update settings

20.  Using mercurial  Download from http://http://mercurial.selenic.com/ http://http://mercurial.selenic.com/  Go to your source code directory  hg init  There’s now a.hg directory  Now “add” the source files to the repository  hg add  Now commit the files to the repository  hg commit

21.  Using mercurial  So, what happened in the repository ?  hg log  Shows the history of changes  User, notes, changeset id and date  In reverse order (latest first)  Let’s make a change to a file ( h-BinCheck.p )  And commit it  hg commit

22.  Using mercurial  Let’s see the log now  hg log  What were the changes ?  hg diff –r0:1 h-BinCheck.p  Let’s make more changes  What is the status of my working directory ?  hg status  What were the changes ?  hg diff

23.  Using mercurial  Don’t like what you see ?  hg revert (creates.orig file)  hg revert –no-backup (no.orig file)

24.  Mercurial Repositories checkout checkin checkout checkin checkout checkin checkout QA RepoBuild Repo

25.  Mercurial Repositories  A “Central” repository is useful for  Providing a master repo for QA  Providing a convenient repo for cloning  Hg serve  Starts a webserver on port 8000  Allows a repo to be accessed by other developers  Server or developer machine  Generally LAN only

26.  Mercurial Repositories  Bitbucket  http://bitbucket.org/ http://bitbucket.org/  Free for up to 5 users  Built-in issue tracking  Unlimited repositories (private / public)  Available wherever there is an internet connection  Demo: Create a new repository (pugus)

27.   Creates a repository from another repository  hg clone https://bitbucket.org/jmls/pugus pugushttps://bitbucket.org/jmls/pugus  Inits the repo  Downloads the entire repository  Updates the working directory  Add a new file, commit  hg add  hg commit Cloning

28.  Repository changesets n/a [empty repository] Repo @ bitbucket 0 My initial version Repo @ my computer

29.  Pushing changes  Now we need to push changes up to remote repo  hg push  Rinse, repeat  make another change “added comments”  commit, push 0 My initial version Repo @ bitbucket 0 My initial version Repo @ my computer

30.  Pushing changes  Now we have  hg push 1 Added comments 0 My initial version Repo @ bitbucket 1 Added comments 0 My initial version Repo @ my computer

31.  Another developer..  Alice has been added to the dev team  Needs to clone the repository  hg clone 1 Added comments 0 My initial version Repo @ bitbucket 1 Added comments 0 My initial version Repo @ Alice 1 Added comments 0 My initial version Repo @ my computer

32.  Multiple changes  I add a new file  Alice modifies readme.txt  Both commit 2 Added install.txt 1 Added comments 0 My initial version Repo @ my computer 2 Added copyright message 1 Added comments 0 My initial version Repo @ Alice

33.  Alice pushes  Alice pushes to remote repo 2 Added copyright message 1 Added comments 0 My initial version Repo @ bitbucket 2 Added copyright message 1 Added comments 0 My initial version Repo @ Alice

34.  I push  I push to remote repo  Fails.  I need to get the updated changesets before I can push  hg incoming  Shows all changes  hg pull  Now there are 2 heads (mine and Alice’s)  Working directory not updated

35.  I push  Merge the two heads  hg merge  Updates working directory  hg commit  hg push

36.   Alice doesn’t have the latest version I push 4 merged changesets 3 Added install.txt 2 Added copyright message 1 Added comments 0 My initial version Repo @ bitbucket 4 Merged changesets 3 Added copyright message 2 Added install.txt 1 Added comments 0 My initial version Repo @ my computer 2 Added copyright message 1 Added comments 0 My initial version Repo @ Alice

37.   Alice doesn’t have the latest version  hg pull  No merge needed, just update  hg update  Alice now has the latest version of the repository Alice pulls 4 Merged changesets 3 Added install.txt 2 Added copyright message 1 Added comments 0 My initial version Repo @ alice

38.  General workflow pullupdate Make changes commitPullMergeTestCommitpush

39.  Workbench demo

40.   Help => Install new Software Mercurial Eclipse

41.   Create new Progress project  File => New=>Other Mercurial Eclipse

44.   To create a Progress view on the project  Select Project Properties  Select Project Facets  Select Openedge / GUI for.net  Apply  Now we have a progress project with a mercurial team  No more command line ;) Mercurial Eclipse