Prefer upstream for main (#943)

* Update docs to configure 'main' to pull from 'upstream'. Ref python/core-workflow#475.

* Quote 'main'.

Co-authored-by: Ezio Melotti <ezio.melotti@gmail.com>

* Direct 'upstream' push to the user's fork. Now pull comes from upstream and push goes to origin.

* Apply the changes also to the git boot camp.

* Prefer https for upstream fetch.

Co-authored-by: C.A.M. Gerlach <CAM.Gerlach@Gerlach.CAM>

* Update expectations and sync guidance for d7e9065. Remove superfluous .git from https.

Co-authored-by: Ezio Melotti <ezio.melotti@gmail.com>
Co-authored-by: C.A.M. Gerlach <CAM.Gerlach@Gerlach.CAM>

Author: 3 people

getting-started/git-boot-camp.rst

@@ -47,17 +47,29 @@ You will only need to do this once.
 Cloning a Forked CPython Repository
 -----------------------------------
 
-You will only need to do this once.  From your command line::
+You will only need to do this once per machine.  From your command line::
 
    git clone git@github.com:<username>/cpython.git
 
 It is also recommended to configure an ``upstream`` remote repository::
 
    cd cpython
-   git remote add upstream git@github.com:python/cpython.git
+   git remote add upstream https://github.com/python/cpython
 
 You can also use SSH-based or HTTPS-based URLs.
 
+Configure the Remotes
+---------------------
+
+Configure ``git`` to pull ``main`` from the ``upstream`` remote::
+
+   git config --local branch.main.remote upstream
+
+Since one should never attempt to push to ``upstream``, configure
+``git`` to push always to ``origin``::
+
+   git remote set-url --push upstream git@github.com:<username>/cpython.git
+
 Listing the Remote Repositories
 -------------------------------
 
@@ -70,8 +82,15 @@ and ``upstream`` pointing to the official CPython repository::
 
    origin  git@github.com:<username>/cpython.git (fetch)
    origin  git@github.com:<username>/cpython.git (push)
-   upstream        git@github.com:python/cpython.git (fetch)
-   upstream        git@github.com:python/cpython.git (push)
+   upstream        https://github.com/python/cpython (fetch)
+   upstream        git@github.com:<username>/cpython.git (push)
+
+To verify the upstream for ``main``::
+
+   git config branch.main.remote
+
+It should emit ``upstream``, indicating to track/pull changes for ``main`` from the
+``upstream`` remote.
 
 
 .. _set-up-name-email:

getting-started/setup-building.rst

@@ -60,7 +60,7 @@ The CPython repo is hosted on GitHub. To get a copy of the source code you shoul
 :ref:`fork the Python repository on GitHub <fork-cpython>`, :ref:`create a local
 clone of your personal fork, and configure the remotes <clone-your-fork>`.
 
-You will only need to execute these steps once:
+You will only need to execute these steps once per machine:
 
 1. Go to https://github.com/python/cpython.
 
@@ -79,15 +79,26 @@ You will only need to execute these steps once:
 6. Configure an ``upstream`` remote::
 
       $ cd cpython
-      $ git remote add upstream git@github.com:python/cpython.git
+      $ git remote add upstream https://github.com/python/cpython
 
-7. Verify that your setup is correct::
+7. Configure ``git`` to pull ``main`` from the ``upstream`` remote::
+
+      $ git config --local branch.main.remote upstream
+
+8. Since one should never attempt to push to ``upstream``, configure
+   ``git`` to push always to ``origin``::
+
+      $ git remote set-url --push upstream git@github.com:<your-username>/cpython.git
+
+9. Verify that your setup is correct::
 
       $ git remote -v
       origin  git@github.com:<your-username>/cpython.git (fetch)
       origin  git@github.com:<your-username>/cpython.git (push)
-      upstream        git@github.com:python/cpython.git (fetch)
-      upstream        git@github.com:python/cpython.git (push)
+      upstream        https://github.com/python/cpython (fetch)
+      upstream        git@github.com:<your-username>/cpython.git (push)
+      $ git config branch.main.remote
+      upstream
 
 If you did everything correctly, you should now have a copy of the code
 in the ``cpython`` directory and two remotes that refer to your own GitHub fork