What is this git log --graph indicating?

Question

I have the following branches:

• master

• upgadingToJquery1.4

• handlingExceptions

I was working on the upgradingToJquery1.4 branch and had made a few commits. I created another branch handlingExceptions made some changes and commited them. Then i switched back to master and merged the handlingExceptions branch. Surprisingly i think the changes in upgardeToJquery1.4 branch also got merged. Then to confirm i merged the upgradToJqueyry1.4 branch and it said up to date.

Can someone just explain what the graph is indicating here?

git log --oneline --decorate --graph --all
    *   a54bd6d (HEAD, master) Merge branch 'upgradeToJquery1.4'
    |\
    | * d4f762c (upgradeToJquery1.4) main.sass updated
    * |   bcf7a4f Merge branch 'handlingExceptions'
    |\ \
    | * | 471c1ad (handlingExceptions) the postLogin method in the accountControlle catches the exceptions and now prov
    | |/
    | * 76145d1 1. css/images - Jquerymobile icon files
    | * 34bc7b9 custom-jqueryMobile.js - to override jquerymobile defaults.Currently added transitions dont work with p

Answer 1

Structurally, you have this (all I have done here is redraw the graph horizontally):

          D    <-- upgradeToJquery1.4
        /   \
- A - B - C   \    <-- handlingExceptions
            \   \
------------- E - F  <-- HEAD=master

where:

A = 34bc7b9 custom-jqueryMobile.js - to ...
B = 76145d1 1. css/images - Jquerymobile icon files
C = 471c1ad the postLogin method in ...
D = d4f762c main.sass updated
E = bcf7a4f Merge branch 'handlingExceptions'
F = a54bd6d Merge branch 'upgradeToJquery1.4'

There are different ways to get here, but given that you created handlingExceptions (presumably with git checkout -b) the most straightforward would probably be this:

git checkout upgradeToJquery1.4
... make commit A (or maybe it was already there but you said make "a few" commits)
... make commit B
git checkout -b handlingExceptions
... make commit C
git checkout upgradeToJquery1.4
... make commit D
git checkout master
git merge handlingExceptions
git merge upgradeToJquery1.4

Another, different way to get here would be:

git checkout upgradeToJquery1.4
... make commits A, B, and D
git checkout HEAD^   # get back onto commit B
git checkout -b handlingExceptions
... make commit C
... now checkout master and merge as before

Or instead of a separate git checkout HEAD^, you could git checkout -b handlingExceptions HEAD^ to create handlingExceptions such that commit C got B as its parent.

In any case, though, at the point at which git merge handlingExceptions occurred, you were on master and handlingExceptions pointed to commit C, so that created commit E. The commit message and graph nodes support each other in this: E's parents are something-not-shown (first parent) and C (2nd parent). Then, while still on master, a separate git merge upgradeToJquery1.4 created commit F, whose parents are E (first-parent) and D (2nd parent).

In any case, the branch labels point to commits D, C, and F now.