Outdated error message from hatchling when default module name selection fails during `hatch shell`

[petermorrowdev]

The error raised here appears to be out of date. I couldn't find any documentation or issues about this change to the build config, so I might be mistaken, but I felt like it was worth reaching out since hatch seems like it's not behaving as expected.

When a project name does not match the (snake_cased) module name hatch shell will throw this error recommend adding this kind of config to your pyproject.toml:

[tool.hatch.build.targets.wheel]
packages = ["src/foo"]

This appears to be incorrect and the correct recommendation seems to be:

[tool.hatch.build]
packages = ["src/foo"]

Looking through the issues I did see #1245 on improving documentation, so maybe this issue is already known. Or maybe I'm configuring hatch incorrectly..

Steps to reproduce issue

I'm using the latest version of hatch.

hatch --version
# Hatch, version 1.13.0

First, create a fresh hatch project called exampleprefix-foo with one module foo.

hatch new exampleprefix-foo
cd exampleprefix-foo
mv src/exampleprefix_foo src/foo

Then adjust the pyproject.toml to reflect the new module name foo removing unnecessary configs along the way.

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

[project]
name = "exampleprefix-foo"
dynamic = ["version"]
description = ''
readme = "README.md"
requires-python = ">=3.8"
license = "MIT"
keywords = []
authors = []
dependencies = []

[tool.hatch.version]
path = "src/foo/__about__.py"

hatch shell with the project in this state will throw the error mentioned above, as expected.

Next, inject the recommended TOML into pyproject.toml

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

[project]
name = "exampleprefix-foo"
dynamic = ["version"]
description = ''
readme = "README.md"
requires-python = ">=3.8"
license = "MIT"
keywords = []
authors = []
dependencies = []

[tool.hatch.version]
path = "src/foo/__about__.py"

# Since we have a module named `foo` in this example we can copy/paste verbatim
[tool.hatch.build.targets.wheel]
packages = ["src/foo"]

This will setup the default env successfully, but the foo package is not installed.

hatch shell
python -c 'import foo'
# Traceback (most recent call last):
#   File "<string>", line 1, in <module>
#     import foo
# ModuleNotFoundError: No module named 'foo'

How to resolve

Swap [tool.hatch.build.targets.wheel] for [tool.hatch.build]

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

[project]
name = "exampleprefix-foo"
dynamic = ["version"]
description = ''
readme = "README.md"
requires-python = ">=3.8"
license = "MIT"
keywords = []
authors = []
dependencies = []

[tool.hatch.version]
path = "src/foo/__about__.py"

[tool.hatch.build]
packages = ["src/foo"]

Then rebuild the hatch shell environment and try again.

hatch env remove
hatch shell
python -c 'import foo'

This works!