Merge #1479

1479: Enable `extension-module` feature in `pyproject.toml` in project templates r=konstin a=messense

Implements #325 (comment).

Thanks for the idea `@jmhodges!`

Co-authored-by: messense <messense@icloud.com>

guide/src/tutorial.md

@@ -37,30 +37,42 @@ rand = "0.8.4"
 
 [dependencies.pyo3]
 version = "0.18.0"
-# "extension-module" tells pyo3 we want to build an extension module (skips linking against libpython.so)
 # "abi3-py37" tells pyo3 (and maturin) to build using the stable ABI with minimum Python version 3.7
-features = ["extension-module", "abi3-py37"]
+features = ["abi3-py37"]
+```
+
+Add a `pyproject.toml` to configure [PEP 518](https://peps.python.org/pep-0518/) build system requirements
+and enable the `extension-module` feature of pyo3.
+
+```toml
+[build-system]
+requires = ["maturin>=0.14,<0.15"]
+build-backend = "maturin"
+
+[tool.maturin]
+# "extension-module" tells pyo3 we want to build an extension module (skips linking against libpython.so)
+features = ["pyo3/extension-module"]
 ```
 
 ### Use `maturin new`
 
 New projects can also be quickly created using the `maturin new` command:
 
 ```bash
-USAGE:
-    maturin new [FLAGS] [OPTIONS] <path>
+maturin new --help
+Create a new cargo project
 
-FLAGS:
-    -h, --help       Prints help information
-        --mixed      Use mixed Rust/Python project layout
-    -V, --version    Prints version information
+Usage: maturin new [OPTIONS] <PATH>
 
-OPTIONS:
-    -b, --bindings <bindings>    Which kind of bindings to use [possible values: pyo3, rust-cpython, cffi, bin]
-        --name <name>            Set the resulting package name, defaults to the directory name
+Arguments:
+  <PATH>  Project path
 
-ARGS:
-    <path>    Project path
+Options:
+      --name <NAME>          Set the resulting package name, defaults to the directory name
+      --mixed                Use mixed Rust/Python project layout
+      --src                  Use Python first src layout for mixed Rust/Python project
+  -b, --bindings <BINDINGS>  Which kind of bindings to use [possible values: pyo3, rust-cpython, cffi, uniffi, bin]
+  -h, --help                 Print help information
 ```
 
 The above process can be achieved by running `maturin new -b pyo3 guessing_game`

src/templates/Cargo.toml.j2

@@ -12,9 +12,9 @@ crate-type = ["cdylib"]
 
 [dependencies]
 {% if bindings == "pyo3" -%}
-pyo3 = { version = "0.18.0", features = ["extension-module"] }
+pyo3 = "0.18.1"
 {% elif bindings == "rust-cpython" -%}
-cpython = { version = "0.7.1", features = ["extension-module"] }
+cpython = "0.7.1"
 {% elif bindings == "uniffi" -%}
 uniffi = "0.21.0"
 uniffi_macros = "0.21.0"

src/templates/pyproject.toml.j2

@@ -14,12 +14,17 @@ classifiers = [
 dependencies = ["cffi"]
 {%- endif %}
 
-{% if bindings == "cffi" or bindings == "bin" or mixed_non_src -%}
+{% if bindings in ["bin", "cffi", "pyo3", "rust-cpython"] or mixed_non_src -%}
 [tool.maturin]
 {% if bindings == "cffi" or bindings == "bin" -%}
 bindings = "{{ bindings }}"
 {% endif -%}
 {% if mixed_non_src -%}
 python-source = "python"
 {% endif -%}
+{% if bindings == "pyo3" -%}
+features = ["pyo3/extension-module"]
+{% elif bindings == "rust-cpython" -%}
+features = ["cpython/extension-module"]
+{% endif -%}
 {% endif -%}