Add src/tox.ini as a standard entrypoint for doctesting

[mkoeppe]

This ticket adds src/tox.ini to advertise the sage doctester to developers familiar with tox.

Later other test environments, such as linters, could be added here - see metaticket #28936.

CC: @embray @videlec @dimpase @vbraun

Component: doctest framework

Author: Matthias Koeppe

Branch/Commit: 109da23

Reviewer: Dima Pasechnik

Issue created by migration from https://trac.sagemath.org/ticket/28987

[mkoeppe]

Branch: public/28987-add-src-tox-ini

[mkoeppe]

Commit: 7bc1ddc

[mkoeppe]

New commits:

7bc1ddc

Add src/tox.ini

[mkoeppe]

Description changed:

--- 
+++ 
@@ -1,4 +1,3 @@
 This ticket adds `src/tox.ini` to advertise the sage doctester to developers familiar with tox.
 
-Later other test environments, such as linters, could be added here.
-
+Later other test environments, such as linters, could be added here - see metaticket #28936.

[embray]

comment:5

As I wrote in #28936 I don't really see the advantage, but, as long as it doesn't hurt...

[dimpase]

comment:7

how should this be tested? I don't know much about tox, especially I don't know what is really does, besides that it's a kind of venv in which some magic happens.

[dimpase]

comment:8

All I can find is #28936#comment:5 - which points at some tox config I don't know how to use.

[sagetrac-git]

Changed commit from 7bc1ddc to e15f33d

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

482dfc4	Add src/tox.ini
e15f33d	src/tox.ini: Add commentss on usage

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

0860f1a

fixup

[sagetrac-git]

Changed commit from e15f33d to 0860f1a

[dimpase]

comment:12

This got to be mentioned in the docs, in en/developer/index.html#running-sage-s-tests

[sagetrac-git]

Changed commit from 0860f1a to 109da23

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

109da23

src/doc/en/developer/doctesting.rst: Mention use of tox

[dimpase]

comment:14

OK!