adding hooks for controlling instances of tests

[pytestbot]

Originally reported by: BitBucket: ddandd, GitHub: ddandd

---

adding pytest_collect_instances(class_item), that will return the test instances of a test_class and each test on an instance will have the same instance object (self)
It should be used when writing long and complicated generated tests, it'll allow calling a setup_instance method that would be able to get funcargs, or calling the init (that will require to add a pytest_collect_can_initialize_class or a similar hook)

---

• Bitbucket: https://bitbucket.org/pytest-dev/pytest/issue/46

[pytestbot]

Original comment by Ronny Pfannschmidt (BitBucket: RonnyPfannschmidt, GitHub: RonnyPfannschmidt):

---

you are outlining a very complex topic, which hard to get right,
specially with only a fuzzy outline of the process/use-cases

could you explain in more depth what your specific use-case is

[pytestbot]

Original comment by holger krekel (BitBucket: hpk42, GitHub: hpk42):

---

also think one or more examples of what you think should work, would help.

You can also describe the pure user-level experience you'd like to see and we discuss hooks/implementation separately.

[pytestbot]

Original comment by Ronny Pfannschmidt (BitBucket: RonnyPfannschmidt, GitHub: RonnyPfannschmidt):

---

can this be closed?

[pytestbot]

Original comment by holger krekel (BitBucket: hpk42, GitHub: hpk42):

---

no more concrete details and examples, closing.