Remove cached_setup and Metafunc.addcall

[nicoddemus]

Removed request.cached_setup and Metafunc.addcall.

Fix #4489, #3083

A note: I had to remove some tests because Metafunc.addcall can combine arguments in multiple levels of pytest_generate_tests hooks, while Metafunc.parametrize specifically has a check against that. For example:

    def test_generate_plugin_and_module(self, testdir):
        testdir.makeconftest(
            """
            def pytest_generate_tests(metafunc):
                assert "arg1" in metafunc.fixturenames
                metafunc.addcall(id="world", param=(2,100))
        """
        )
        p = testdir.makepyfile(
            """
            def pytest_generate_tests(metafunc):
                metafunc.addcall(param=(1,1), id="hello")

            import pytest
            @pytest.fixture
            def arg1(request):
                return request.param[0]
            @pytest.fixture
            def arg2(request):
                return request.param[1]

            class TestClass(object):
                def test_myfunc(self, arg1, arg2):
                    assert arg1 == arg2
        """
        )
        result = testdir.runpytest("-v", p, SHOW_PYTEST_WARNINGS_ARG)
        result.stdout.fnmatch_lines(
            [
                "*test_myfunc*hello*PASS*",
                "*test_myfunc*world*FAIL*",
                "*1 failed, 1 passed*",
            ]
        )

When converted to use metafunc.parametrize:

    def test_generate_plugin_and_module(self, testdir):
        testdir.makeconftest(
            """
            def pytest_generate_tests(metafunc):
                assert "arg1" in metafunc.fixturenames
                metafunc.parametrize('arg1, arg2', [(2, 100)], ids=["world"])
        """
        )
        p = testdir.makepyfile(
            """
            def pytest_generate_tests(metafunc):
                metafunc.parametrize('arg1, arg2', [(1, 1)], ids=["hello"])    

            class TestClass(object):
                def test_myfunc(self, arg1, arg2):
                    assert arg1 == arg2
        """
        )
        result = testdir.runpytest("-v", p, SHOW_PYTEST_WARNINGS_ARG)
        result.stdout.fnmatch_lines(
            [
                "*test_myfunc*hello*PASS*",
                "*test_myfunc*world*FAIL*",
                "*1 failed, 1 passed*",
            ]
        )

We get this error:

ValueError: duplicate 'arg1'

I think this is fine, as users who might still rely on cached_setup's behavior would have probably complain by now.

[asottile]

pretty clean break! nice!

[RonnyPfannschmidt]

this looks good, we ought to investigate which of the changed tests are better removed - i beleive 2-3 of them might be better gone

[codecov]

Codecov Report

Merging #4490 into features will decrease coverage by 0.05%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##           features    #4490      +/-   ##
============================================
- Coverage     95.82%   95.76%   -0.06%     
============================================
  Files           111      111              
  Lines         25038    24853     -185     
  Branches       2463     2455       -8     
============================================
- Hits          23992    23801     -191     
- Misses          736      741       +5     
- Partials        310      311       +1

Flag	Coverage Δ
#docs	29.36% <100%> (+0.12%)	⬆️
#doctesting	29.36% <100%> (+0.12%)	⬆️
#linting	29.36% <100%> (+0.12%)	⬆️
#linux	95.59% <100%> (-0.06%)	⬇️
#nobyte	92.47% <100%> (-0.08%)	⬇️
#numpy	93.2% <100%> (-0.11%)	⬇️
#pexpect	41.71% <100%> (+0.05%)	⬆️
#py27	93.81% <100%> (-0.07%)	⬇️
#py34	91.98% <100%> (-0.02%)	⬇️
#py35	92% <100%> (-0.02%)	⬇️
#py36	92.02% <100%> (-0.02%)	⬇️
#py37	93.95% <100%> (-0.05%)	⬇️
#trial	93.2% <100%> (-0.11%)	⬇️
#windows	94.01% <100%> (-0.07%)	⬇️
#xdist	93.85% <100%> (-0.08%)	⬇️

Impacted Files	Coverage Δ
src/_pytest/python.py	93.05% <ø> (-1.55%)	⬇️
testing/python/metafunc.py	95.77% <ø> (+0.41%)	⬆️
testing/deprecated_test.py	100% <ø> (ø)	⬆️
src/_pytest/deprecated.py	100% <ø> (ø)	⬆️
testing/acceptance_test.py	98.28% <ø> (ø)	⬆️
testing/python/fixture.py	99.19% <100%> (-0.05%)	⬇️
src/_pytest/fixtures.py	97.18% <100%> (-0.21%)	⬇️

---

Continue to review full report at Codecov.

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #4490 into features will decrease coverage by 0.05%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##           features    #4490      +/-   ##
============================================
- Coverage     95.82%   95.76%   -0.06%     
============================================
  Files           111      111              
  Lines         25038    24853     -185     
  Branches       2463     2455       -8     
============================================
- Hits          23992    23801     -191     
- Misses          736      741       +5     
- Partials        310      311       +1

Flag	Coverage Δ
#docs	29.36% <100%> (+0.12%)	⬆️
#doctesting	29.36% <100%> (+0.12%)	⬆️
#linting	29.36% <100%> (+0.12%)	⬆️
#linux	95.59% <100%> (-0.06%)	⬇️
#nobyte	92.47% <100%> (-0.08%)	⬇️
#numpy	93.2% <100%> (-0.11%)	⬇️
#pexpect	41.71% <100%> (+0.05%)	⬆️
#py27	93.81% <100%> (-0.07%)	⬇️
#py34	91.98% <100%> (-0.02%)	⬇️
#py35	92% <100%> (-0.02%)	⬇️
#py36	92.02% <100%> (-0.02%)	⬇️
#py37	93.95% <100%> (-0.05%)	⬇️
#trial	93.2% <100%> (-0.11%)	⬇️
#windows	94.01% <100%> (-0.07%)	⬇️
#xdist	93.85% <100%> (-0.08%)	⬇️

Impacted Files	Coverage Δ
src/_pytest/python.py	93.05% <ø> (-1.55%)	⬇️
testing/python/metafunc.py	95.77% <ø> (+0.41%)	⬆️
testing/deprecated_test.py	100% <ø> (ø)	⬆️
src/_pytest/deprecated.py	100% <ø> (ø)	⬆️
testing/acceptance_test.py	98.28% <ø> (ø)	⬆️
testing/python/fixture.py	99.19% <100%> (-0.05%)	⬇️
src/_pytest/fixtures.py	97.18% <100%> (-0.21%)	⬇️

---

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Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 06dc6e3...40b85d7. Read the comment docs.