Feature : provide Path accesssors

[SSE4]

closes: #11304

Changelog: Feature: Provide Path accessors in Conanfile.
Docs: omit

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[memsharded]

Please add some basic integration test that checks these added methods.

[memsharded]

This one disappears in 2.0, better remove it.

[SSE4]

removed

[memsharded]

This one disappears in 2.0, better remove it.

[SSE4]

removed

[memsharded]

This one disappears in 2.0, better remove it.

[SSE4]

removed

[memsharded]

I'd say that the Folders xxxx_folder are not intended nor documented for users yet.
If anything we want to replace the xxx_folder for the path alternatives. But this is not necessary in this PR, as this is intended only for user recipes which is always self.xxxx_path, and not self.folders.xxxx_path.

So maybe leave this file untouched.

[SSE4]

okay, I left it untouched

[SSE4]

Please add some basic integration test that checks these added methods.

added (updated an existing test with more checks)

[ytimenkov]

Out of curiosity: why not to change existing fields but add new ones? What are the potential issues with changing the type?

[SSE4]

Out of curiosity: why not to change existing fields but add new ones? What are the potential issues with changing the type?

it may break existing recipes. e.g. the one doing something like isinstance(self.package_folder, str) or similar.

[ytimenkov]

it may break existing recipes. e.g. the one doing something like isinstance(self.package_folder, str) or similar.

Thank you for quick reply. That part I have figured out. Was more interested if there are recipes which do this and why.

In my limited python experience calling isinstance is discouraged. The most common check for type I know is str vs list of strings (where str is converted to a single-element list, but the check is for list, because it can be something else) for caller convenience. Other examples str vs bytes - just call encode, and there is is None for optionals.

[SSE4]

I don't know any recipe doing it out of my mind. still, it's possible, some recipe does some_python_func(self.package_folder) where some_python_func calls is_instance under the hood.

nethertheless, there could be other breaking cases, e.g.:

var = self.package_folder.replace("foo", "bar")

will crash if self.package_folder is pathlib.Path, but it will work if it's just a regular string. and replace for sure is done in many recipes.
an example: https://github.com/conan-io/conan-center-index/blob/c102ed11805c88f636198d1feec892eea8c20579/recipes/bison/all/conanfile.py#L156

for sure it could be changed in 2.0, but for 1.x I would say it's too risky.

[memsharded]

I am merging this because it is done, but after talking to the team, please let me clarify:

• We really, really need to stop adding new things to Conan 1.X. Only add things that are strictly necessary for the migration to 2.0. This was clearly not necessary.
• We will not document it yet, now things added to 1.X basically need to be documented twice, and in 2.0 is complicated because we are still discussing many things around the docs.
• This will be there as experimental and not supported yet. If it becomes a maintenance or support burden, we will remove it, but we will not invest more time in things that could derive from this feature, until Conan 2.X

Thanks for understanding