Broken Import Hooks for Editable Installs?

[rmorshea]

Right now, I have a package which installs a in import hook. That is, it includes a .pth file. The normal install works great via pip install .. However, the editable install via pip install -e . or the version installed by hatch shell is broken. When the import hook is triggered it complains that it cannot find my package. I suspect this is a bug or a limitation. Any help is appreciated.

Useful Links:

• pyproject.toml
• src/ directory
• .pth file

[ofek]

You need a custom build hook in order to use the force_include_editable option.

[project]
name = "tagstr"
readme = "README.md"
dynamic = ["version"]
requires-python = ">=3.8"
description = "Tagged template literals for Python"

[tool.hatch.version]
path = "src/tagstr/__init__.py"

[tool.hatch.build.targets.wheel.hooks.custom]

[build-system]
requires = ["hatchling"]
build-backend = "hatchling.build"

hatch_build.py:

from hatchling.builders.hooks.plugin.interface import BuildHookInterface

class CustomBuildHook(BuildHookInterface):
    def initialize(self, version, build_data):
        if version == 'editable':
            build_data['force_include_editable'] = {'src/tagstr.pth': 'tagstr.pth'}

[ofek]

For editable installs the only file that gets included in site-packages is a generated PTH file that points to, in your case, the src directory. As far as I know recursive PTH loading is not a thing which is why you have to define extra files to ship.

[ofek]

Oh I see, the PTH file that Hatchling creates uses the package name and your file overwrites that.

[project]
name = "tagstr"
readme = "README.md"
dynamic = ["version"]
requires-python = ">=3.8"
description = "Tagged template literals for Python"

[tool.hatch.version]
path = "src/tagstr/__init__.py"

[tool.hatch.build.targets.wheel.force-include]
"src/tagstr.pth" = "_tagstr.pth"

[build-system]
requires = ["hatchling"]
build-backend = "hatchling.build"

[rmorshea]

I have no idea why, but it seems like I need to name my .pth file such that it comes alphabetically after the one inserted by Hatch. So instead of naming it _tagstr.pth I need to name it z_tagstr.pth. Somehow this seems to make the tagstr.pth inserted by Hatch get evaluated first so that tagstr is in the PATH before my import hook tries to load it.

[rmorshea]

There is mention in the docs of behavior that depends on the alphabetical order of the .pth files:

Note that bletch is omitted because it doesn’t exist; the bar directory precedes the foo directory because bar.pth comes alphabetically before foo.pth; and spam is omitted because it is not mentioned in either path configuration file.

This suggests that it might be better for the .pth file inserted by Hatch to be named something like _<the-package-name>.pth since the purpose of a .pth file is often to import the associated package.

[rmorshea]

Took a shot in the dark at a possible fix: #828