Refs #11662.
--- Problem
Each fixture definition has a "visibility", the `FixtureDef.baseid`
attribute. This is nodeid-like string. When a certain `node` requests a
certain fixture name, we match node's nodeid against the fixture
definitions with this name.
The matching currently happens on the *textual* representation of the
nodeid - we split `node.nodeid` to its "parent nodeids" and then check
if the fixture's `baseid` is in there.
While this has worked so far, we really should try to avoid textual
manipulation of nodeids as much as possible. It has also caused problem
in an odd case of a `Package` in the root directory: the `Package` gets
nodeid `.`, while a `Module` in it gets nodeid `test_module.py`. And
textually, `.` is not a parent of `test_module.py`.
--- Solution
Avoid this entirely by just checking the node hierarchy itself. This is
made possible by the fact that we now have proper `Directory` nodes
(`Dir` or `Package`) for the entire hierarchy.
Also do the same for `_getautousenames` which is a similar deal.
The `iterparentnodeids` function is no longer used and is removed.
Instead of modifying user objects like modules and classes that we
really shouldn't be touching, use the new `_register_fixture` internal
API to do it directly.
Add a function on the `FixtureManager` to register a fixture with
pytest. Currently this can only be done through `parsefactories`.
My aim is to eventually make something like this available to plugins,
as it's a pretty common need.
* Fix handling empty values of NO_COLOR and FORCE_COLOR
Fix handling NO_COLOR and FORCE_COLOR environment variables to correctly
be ignored when they are set to an empty value, as defined
in the specification:
> Command-line software which adds ANSI color to its output by default
> should check for a NO_COLOR environment variable that, when present
> *and not an empty string* (regardless of its value), prevents
> the addition of ANSI color.
(emphasis mine, https://no-color.org/)
The same is true of FORCE_COLOR, https://force-color.org/.
* Streamline testing for FORCE_COLOR and NO_COLOR
Streamline the tests for FORCE_COLOR and NO_COLOR variables, and cover
all possible cases (unset, set to empty, set to "1"). Combine the two
assert functions into one taking boolean parameters. Mock file.isatty
in all circumstances to ensure that the environment variables take
precedence over the fallback value resulting from isatty check (or that
the fallback is actually used, in the case of both FORCE_COLOR
and NO_COLOR being unset).
* Put a 'reset' color in front of the highlighting
When doing the highlighting, some lexers will not set the initial color
explicitly, which may lead to the red from the errors being propagated
to the start of the expression
* Add syntactic highlighting to the error explanations
This updates the various error reporting to highlight python code when
displayed, to increase readability and make it easier to understand
--- Current main
In current main (before pervious commit), calls to gethookproxy/ihook
are the trigger for loading non-initial conftests. This basically means
that conftest loading is done almost as a random side-effect,
uncontrolled and very non-obvious. And it also dashes any hope of making
gethookproxy faster (gethookproxy shows up prominently in pytest
profiles).
I've wanted to improve this for a while, #11268 was the latest step
towards that.
--- PR before change
In this PR, I ran into a problem.
Previously, Session and Package did all of the directory traversals
inside of their collect, which loaded the conftests as a side effect. If
the conftest loading failed, it will occur inside of the collect() and
cause it to be reported as a failure.
Now I've changed things such that Session.collect and Package.collect no
longer recurse, but just collect their immediate descendants, and
genitems does the recursive expansion work.
The problem though is that genitems() doesn't run inside of specific
collector's collect context. So when it loads a conftest, and the
conftest loading fails, the exception isn't handled by any CollectReport
and causes an internal error instead.
The way I've fixed this problem is by loading the conftests eagerly in a
pytest_collect_directory post-wrapper, but only during genitems to make
sure the directory is actually selected.
This solution in turn caused the conftests to be collected too early;
specifically, the plugins are loaded during the parent's collect(), one
after the other as the directory entries are collected. So when the
ihook is hoisted out of the loop, new plugins are loaded inside the
loop, and due to the way the hook proxy works, they are added to the
ihook even though they're supposed to be scoped to the child collectors.
So no hoisting.
--- PR after change
Now I've come up with a better solution: since now the collection tree
actually reflects the filesystem tree, what we really want is to load
the conftest of a directory right before we run its collect(). A
conftest can affect a directory's collect() (e.g. with a
pytest_ignore_collect hookimpl), but it cannot affect how the directory
node itself is collected. So I just moved the conftest loading to be
done right before calling collect, but still inside the CollectReport
context.
This allows the hoisting, and also removes conftest loading from
gethookproxy since it's no longer necessary. And it will probably enable
further cleanups. So I'm happy with it.
Previously the error report would have all sections glued together:
- The assertion representation
- The error explanation
- The full diff
This makes it hard to see at a glance where which one starts and ends.
One of the representation (dataclasses, tuples, attrs) does display a
newlines at the start already.
Let's add a newlines before the error explanation and before the full
diff, so we get an easier to read report.
This has one disadvantage: we get one line less in the least verbose
mode, where the output gets truncated.
Ran Benita
Fabian Sturm
Clément Robert
Ben Brown
Marc Bresson
Michał Górny
Benjamin Schubert
Arthur Richard