[BUG] distutils.ccompiler.CCompiler.has_function does not quote provided includes anymore

[rokm]

setuptools version

67.2.0

Python version

3.x

OS

Linux (but presumably applicable to all)

Additional environment information

No response

Description

As of 56a5b33 (setuptools 67.2.0), the distutils.ccompiler.CCompiler.has_function in the setuptools-provided distutils ceased to quote the provided includes in the generated test C file (here).

Therefore, the compilation of the generated test C file always fails.

Expected behavior

The provided includes should be quoted (as before the change) to retain compatibility with older code using this function.

How to Reproduce

1. Run the following test code on Linux:

# program.py
import distutils.ccompiler

# Check for `clock` function in the standard library
cc = distutils.ccompiler.new_compiler()
has_clock = cc.has_function('clock', includes=['time.h'])
print("Has clock:" , has_clock)

Output

With setuptools 67.2.0:

$ python program.py 
/tmp/clocku2l593gf.c:1:10: error: #include expects "FILENAME" or <FILENAME>
    1 | #include time.h
      |          ^~~~
/tmp/clocku2l593gf.c: In function ‘main’:
/tmp/clocku2l593gf.c:3:5: warning: implicit declaration of function ‘clock’ [-Wimplicit-function-declaration]
    3 |     clock();
      |     ^~~~~
/tmp/clocku2l593gf.c:1:1: note: ‘clock’ is defined in header ‘<time.h>’; did you forget to ‘#include <time.h>’?
  +++ |+#include <time.h>
    1 | #include time.h
Has clock: False

With setuptools 67.1.0:

$ python program.py 
Has clock: True

[lazka]

@fweimer-rh

[fweimer-rh]

Yeah, this was clearly an error on my part. I view "" and <> as part of header specification (and they are not interchangeable), but it's too late to change this now, and I had not noticed that I was altering behavior in this way.

[fweimer-rh]

Should I send a PR to fix this?

[abravalheri]

@fweimer-rh, would it be possible to add quotes if the argument does not start with " either <?

[abravalheri]

Should I send a PR to fix this?

I believe that a PR to pypa/distutils mentioning this bug in setuptools should be the way to go.

[fweimer-rh]

@fweimer-rh, would it be possible to add quotes if the argument does not start with " either <?

I would prefer to fix just this bug, it's an obsolete feature anyway because the headers won't work for function that take any parameters (and most functions do). Sorry for messing this up.