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@@ -190,3 +190,50 @@ $ git tag -a v1.2 a6b4c9
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## Chapter 3: Git Branches
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+### What are branches
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+* When committing, git stores an object with:
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+ - pointer to the snapshot of the content you staged
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+ - authors name and email
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+ - the message you typed
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+ - pointers to the commit(s) that directly came before this commit (parents)
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+ * zero parents for initial commit
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+ * one parent for normal commits
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+ * multiple parents for merges
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+* Therefore, in git a branch is a lightweight pointer to one of these commits
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+* The default branch name is `master`
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+
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+### Working with branches
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+* Creating a new branch `$ git branch testing`
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+ - creates a new pointer to the same commit
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+* HEAD is a special pointer that points at the commit you're currently on
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+* Switch branches `$ git checkout testing`
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+ - This moves the HEAD cursor to testing
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+* Creating a branch is lightweight (writing the 40byte hash + a newline to a file)
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+* Shorthand for branching and switching `$ git checkout -b testing`
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+* Switching is not allowed, if there are uncommitted changes in a branch
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+
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+### Basic merging
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+* Merge another branch into the current one: `$ git merge testing`
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+* If a file was edited in more than one branch, a conflict will result and needs to be resolved before the next checkin.
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+* you can manually resolve the conflict or use `$ git mergetool`
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+* After the resolution, you can commit the changes.
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+
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+### Branch management
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+* `$ git branch` gives a list of current branches.
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+* `$ git branch -v` gives the same list, but with the latest commit messages.
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+* To see what branches are already merged, use `$ git branch --merged`
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+* To see what branches that haven't been merged yet, use `$ git branch --un-merged`
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+* Deleting branches that haven't been merged fails.
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+
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+### Branching workflows
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+1. Long running branches
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+ * Used like different levels of hierarchy
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+ * Basically one long linear line of commits, branches used as tags.
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+ * Can be used to achieve different levels of stability
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+1. Topic branches
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+ * Branches diverge at any point
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+ * allows to context-switch quickly
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+ * can keep different parts of development isolated for longer times
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+ * more challenging to merge.
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+
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+
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Tomi Cvetic