Move all function introspection/argument generation into new classes.

Review Request #10920 — Created Feb. 26, 2020 and submitted

Information

kgb
master

Reviewers

kgb

As FunctionSpy got more complicated and continued to add compatibility
with newer versions of Python, the code got increasingly complex and
littered with Python version checks. This could make it more challenging
to reason about some parts of code.

To address this, this change introduces a new set of FunctionSig
classes, which consist of BaseFunctionSig, FunctionSigPy2, and
FunctionSigPy3.

These are responsible for taking a function and storing information on
the function type, owner, and arguments. It's also responsible for
generating code for a function's argument signature or for referencing a
variable defined in a spy-generated function, for the purposes of
generating those functions.

The Py2 and Py3 versions of these classes implement the logic for
Python 2 and Python 3, respectively. There's some common logic in the
base class, but the bulk are in these. They also contain constants used
for function attribute states, which used to be defined per-version in
spies.py.

A FunctionSig alias exists that points to the appropriate class for
the current version of Python.

FunctionSpy generates an instance of this for the provided function
up-front, and uses it to figure out the owner and other information. It
ditches the argspec-related methods in favor of calls to this. It also
provides some property wrappers for attributes on the signature, for
compatibility purposes.

Version checks are still required in FunctionSpy for many purposes,
such as when filling out attributes for a CodeType or FunctionType,
but a lot of the complexities are now isolated to the FunctionSigs.

This should help keep the codebase more maintainable and future-proof as
we go on.

Unit tests pass on Python 2.7 and 3.5-3.8.

Ran Djblets and Review Board unit test suites with these Python
versions to make sure nothing broke in real-world usage.

Summary ID
Move all function introspection/argument generation into new classes.
As `FunctionSpy` got more complicated and continued to add compatibility with newer versions of Python, the code got increasingly complex and littered with Python version checks. This could make it more challenging to reason about some parts of code. To address this, this change introduces a new set of `FunctionSig` classes, which consist of `BaseFunctionSig`, `FunctionSigPy2`, and `FunctionSigPy3`. These are responsible for taking a function and storing information on the function type, owner, and arguments. It's also responsible for generating code for a function's argument signature or for referencing a variable defined in a spy-generated function, for the purposes of generating those functions. The `Py2` and `Py3` versions of these classes implement the logic for Python 2 and Python 3, respectively. There's some common logic in the base class, but the bulk are in these. They also contain constants used for function attribute states, which used to be defined per-version in `spies.py`. A `FunctionSig` alias exists that points to the appropriate class for the current version of Python. `FunctionSpy` generates an instance of this for the provided function up-front, and uses it to figure out the owner and other information. It ditches the argspec-related methods in favor of calls to this. It also provides some property wrappers for attributes on the signature, for compatibility purposes. Version checks are still required in `FunctionSpy` for many purposes, such as when filling out attributes for a `CodeType` or `FunctionType`, but a lot of the complexities are now isolated to the `FunctionSig`s. This should help keep the codebase more maintainable and future-proof as we go on.
e3f3f5ea5c02167d15d12f8ccf4ec795881aaa84
Description From Last Updated

E127 continuation line over-indented for visual indent

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E127 continuation line over-indented for visual indent

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E127 continuation line over-indented for visual indent

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chipx86
david
  1. Nice cleanup!

  2. 
      
chipx86
Review request changed

Status: Closed (submitted)

Change Summary:

Pushed to master (d5de4e1)
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