[GRASS-user] Using new git master

[Rich Shepard]

I've not needed GRASS for a while, but now I need to model hydrology for a
location.

Here, I removed the source directory ~/gis/grass/grass7_trunk/ which used to
be updated from the svn repository. I tried to replace the source with that
in the github master but failed. Please show me what I missed.

Following this instruction: "The GRASS GIS software lives in the Git source
control system hosted by GitHub. It can be browsed online using
GitHub UI. With the Git client software installed, various versions
can be accessed:
   git clone https://github.com/OSGeo/grass.git"

$ git clone https://github.com/OSGeo/grass.git
Cloning into 'grass'...
remote: Enumerating objects: 120, done.
remote: Counting objects: 100% (120/120), done.
remote: Compressing objects: 100% (110/110), done.
remote: Total 229474 (delta 77), reused 35 (delta 10), pack-reused 229354
Receiving objects: 100% (229474/229474), 237.22 MiB | 1.78 MiB/s, done.
Resolving deltas: 100% (169917/169917), done.
Checking out files: 100% (7360/7360), done.

I see nothing different in ~/gis/grass; there's not a git repo there.
Anyway, I try:

$ git checkout master
fatal: Not a git repository (or any parent up to mount point /)
Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).

Should I initialize a local repo (git init) in ~/gis/grass before cloning
and checking out the master?

TIA,

Rich