Implement PEP 723 support (script dependencies in a TOML block)

README.rst

@@ -209,6 +209,12 @@ variable or ``# Requirements:`` section to the script:
     # Requirements:
     # requests
 
+    # or (PEP 723)
+
+    # /// script
+    # dependencies = ['requests']
+    # ///
+
     import requests
 
     req = requests.get('https://pypi.org/project/pip-run')

newsfragments/+96.feature.rst

@@ -0,0 +1 @@
+Add support for script dependencies in a TOML block per PEP 723.

pip_run/compat/py310.py

@@ -0,0 +1,8 @@
+"""
+Compatibility for Python 3.10 and earlier.
+"""
+
+try:
+    import tomllib  # type: ignore
+except ImportError:  # pragma: no cover
+    import tomli as tomllib  # type: ignore

pip_run/scripts.py

@@ -11,6 +11,9 @@
 from jaraco.context import suppress
 from jaraco.functools import compose
 
+from .compat.py310 import tomllib
+
+
 ValidRequirementString = compose(str, packaging.requirements.Requirement)
 
 
@@ -73,7 +76,39 @@ def search(cls, params):
         return cls.try_read(next(files, None)).params()
 
     def read(self):
-        return self.read_comments() or self.read_python()
+        return self.read_toml() or self.read_comments() or self.read_python()
+
+    def read_toml(self):
+        r"""
+        >>> DepsReader('# /// script\n# dependencies = ["foo", "bar"]\n# ///\n').read()
+        ['foo', 'bar']
+        >>> DepsReader('# /// pyproject\n# dependencies = ["foo", "bar"]\n# ///\n').read_toml()
+        []
+        >>> DepsReader('# /// pyproject\n#dependencies = ["foo", "bar"]\n# ///\n').read_toml()
+        []
+        >>> DepsReader('# /// script\n# dependencies = ["foo", "bar"]\n').read_toml()
+        []
+        >>> DepsReader('# /// script\n# ///\n\n# /// script\n# ///').read_toml()
+        Traceback (most recent call last):
+        ...
+        ValueError: Multiple script blocks found
+        """
+        TOML_BLOCK_REGEX = r'(?m)^# /// (?P<type>[a-zA-Z0-9-]+)$\s(?P<content>(^#(| .*)$\s)*)^# ///$'
+        name = 'script'
+        matches = list(
+            filter(lambda m: m.group('type') == name, re.finditer(TOML_BLOCK_REGEX, self.script))
+        )
+        if len(matches) > 1:
+            raise ValueError(f'Multiple {name} blocks found')
+        elif len(matches) == 1:
+            content = ''.join(
+                line[2:] if line.startswith('# ') else line[1:]
+                for line in matches[0].group('content').splitlines(keepends=True)
+            )
+            deps = tomllib.loads(content).get("dependencies", [])
+        else:
+            deps = []
+        return Dependencies.load(deps)
 
     def read_comments(self):
         r"""

setup.cfg

@@ -26,6 +26,7 @@ install_requires =
 	jaraco.context
 	jaraco.text
 	platformdirs
+	tomli; python_version < "3.11"
 	importlib_resources; python_version < "3.9"
 	jaraco.functools >= 3.7
 	jaraco.env

tests/test_scripts.py

@@ -111,6 +111,19 @@ def test_comment_style(self):
         reqs = scripts.DepsReader(script).read()
         assert reqs == ['foo==3.1']
 
+    def test_toml_style(self):
+        script = textwrap.dedent(
+            """
+            #! shebang
+
+            # /// script
+            # dependencies = ["foo == 3.1"]
+            # ///
+            """
+        )
+        reqs = scripts.DepsReader(script).read()
+        assert reqs == ['foo==3.1']
+
     def test_search_long_parameter(self):
         """
         A parameter that is too long to be a filename should not fail.