Revert "tests: Use separate virtual environment for avocado"

This reverts commit e8e4298feadae7924cf7600bb3bcc5b0a8d7cbe9.

ensuregroup allows to specify both the acceptable versions of avocado,
and a locked version to be used when avocado is not installed as a system
pacakge.  This lets us install avocado in pyvenv/ using "mkvenv.py" and
reuse the distro package on Fedora and CentOS Stream (the only distros
where it's available).

ensuregroup's usage of "(>=..., <=...)" constraints when evaluating
the distro package, and "==" constraints when installing it from PyPI,
makes it possible to avoid conflicts between the known-good version and
a package plugins included in the distro.

This is because package plugins have "==" constraints on the version
that is included in the distro, and, using "pip install avocado==88.1"
on a venv that includes system packages will result in an error:

   avocado-framework-plugin-varianter-yaml-to-mux 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.
   avocado-framework-plugin-result-html 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.

But at the same time, if the venv does not include a system distribution
of avocado then we can install a known-good version and stick to LTS
releases.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1663
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 7 insertions, 7 deletions

diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index b6ad21bed1..5d1fc0aa95 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -894,9 +894,9 @@ You can run the avocado tests simply by executing:
 
   make check-avocado
 
-This involves the automatic creation of Python virtual environment
-within the build tree (at ``tests/venv``) which will have all the
-right dependencies, and will save tests results also within the
+This involves the automatic installation, from PyPI, of all the
+necessary avocado-framework dependencies into the QEMU venv within the
+build tree (at ``./pyvenv``). Test results are also saved within the
 build tree (at ``tests/results``).
 
 Note: the build environment must be using a Python 3 stack, and have
@@ -953,7 +953,7 @@ may be invoked by running:
 
  .. code::
 
-  tests/venv/bin/avocado run $OPTION1 $OPTION2 tests/avocado/
+  pyvenv/bin/avocado run $OPTION1 $OPTION2 tests/avocado/
 
 Note that if ``make check-avocado`` was not executed before, it is
 possible to create the Python virtual environment with the dependencies
@@ -968,20 +968,20 @@ a test file. To run tests from a single file within the build tree, use:
 
  .. code::
 
-  tests/venv/bin/avocado run tests/avocado/$TESTFILE
+  pyvenv/bin/avocado run tests/avocado/$TESTFILE
 
 To run a single test within a test file, use:
 
  .. code::
 
-  tests/venv/bin/avocado run tests/avocado/$TESTFILE:$TESTCLASS.$TESTNAME
+  pyvenv/bin/avocado run tests/avocado/$TESTFILE:$TESTCLASS.$TESTNAME
 
 Valid test names are visible in the output from any previous execution
 of Avocado or ``make check-avocado``, and can also be queried using:
 
  .. code::
 
-  tests/venv/bin/avocado list tests/avocado
+  pyvenv/bin/avocado list tests/avocado
 
 Manual Installation
 ~~~~~~~~~~~~~~~~~~~