Documenting how to download Metalava via `repo`
Change-Id: Ia9e2ce8f55c0837d77605e59a165080515319dc2
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+# Checking out Metalava
+
+Metalava can be downloaded from the `metalava-master` manifest branch via `repo` as explained below
+
+## To check out `metalava-master` using `repo`:
+1. Install `repo` (Repo is a tool that makes it easier to download multiple Git repositories at once. For more information about Repo, see the [Repo Command Reference](https://source.android.com/setup/develop/repo))
+
+```bash
+mkdir ~/bin
+PATH=~/bin:$PATH
+curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
+chmod a+x ~/bin/repo
+```
+
+2. Configure Git with your real name and email address.
+
+```bash
+git config --global user.name "Your Name"
+git config --global user.email "[email protected]"
+```
+
+3. Create a directory for your checkout (it can be any name)
+
+```bash
+mkdir metalava-master
+cd metalava-master
+```
+
+4. Use `repo` command to initialize the repository.
+
+```bash
+repo init -u https://android.googlesource.com/platform/manifest -b metalava-master
+```
+
+5. Now your repository is configured to pull only what you need for building and running Metalava. Download the code (this may take some time; the checkout is about 1.7G):
+
+```bash
+repo sync -j8 -c
+```
+## Checking out `aosp/master` instead:
+
+For anyone that is already working in the `aosp/master` branch, you can use that repo checkout instead. For small changes to metalava, this is not recommended - it is a very large checkout, with many dependencies not used by metalava.
+
+## Developing
+
+See also [README.md](README.md) for details about building and running Metalava after you have checked out the code.
+
