build: make authors optional in setup converter

CHANGELOG.md

@@ -10,10 +10,15 @@ and this project adheres to
 
 ### Added
 
-- build::
+- build:
   - Support setuptools.packages.find.where directive in setup converter.
   - Support setuptools.data-files directives in setup converter.
 
+### Changed
+
+- build: Make `authors` optional in setup converter (omit `author` and
+  `author_email` when not specified).
+
 ## [1.8.0] - 2026-05-22
 
 ### Added

src/build/README.md

@@ -38,7 +38,7 @@ arguments:
 | Source | `setup()` argument |
 |--------|-------------------|
 | `[project]` `name`, `version` | `name`, `version` |
-| `[project]` `authors[0]` | `author`, `author_email` |
+| `[project]` `authors[0]` (optional) | `author`, `author_email` (each only when present) |
 | `[project]` `scripts` | `entry_points["console_scripts"]` |
 | `[project]` `dependencies` | `install_requires` |
 | `[project]` `optional-dependencies` | `extras_require` |
@@ -116,7 +116,9 @@ The converter is intentionally minimal. It does **not** map many common
 - `[tool.setuptools]` `package-dir` as an explicit pyproject key (only inferred from
   `where`)
 
-Only the first `[project]` author entry is used.
+When `[project].authors` is present, only the first entry is used; `name` and
+`email` are each passed to `setup()` only when specified. When `authors` is absent
+or empty, no author metadata is passed.
 
 The script must be executed from the directory that contains `pyproject.toml`. It
 requires `tomllib` (Python 3.11+) or the `tomli` package on older Python versions.

src/build/rfl/build/scripts/setup

@@ -166,11 +166,16 @@ elif "file" in pyproject["project"]["license"]:
 if "urls" in pyproject["project"]:
     kwargs["url"] = pyproject["project"]["urls"]["Homepage"]
 
+authors = pyproject["project"].get("authors") or []
+if authors:
+    if "name" in authors[0]:
+        kwargs["author"] = authors[0]["name"]
+    if "email" in authors[0]:
+        kwargs["author_email"] = authors[0]["email"]
+
 setup(
     name=pyproject["project"]["name"],
     version=pyproject["project"]["version"],
-    author=pyproject["project"]["authors"][0]["name"],
-    author_email=pyproject["project"]["authors"][0]["email"],
     platforms=["GNU/Linux"],
     **kwargs,
 )

src/build/rfl/tests/test_setup.py

@@ -29,18 +29,27 @@ def _run_setup_script():
     exec(compile(code, str(path), "exec"), {"__name__": "__main__"})
 
 
-def _minimal_pyproject(extra="", license_line='license = "LGPL-3.0-or-later"'):
+def _minimal_pyproject(
+    extra="",
+    license_line='license = "LGPL-3.0-or-later"',
+    authors_block=textwrap.dedent(
+        """\
+        authors = [
+            {name = "Test Author", email = "test@example.com"},
+        ]
+        """
+    ),
+):
     content = textwrap.dedent(
         f"""\
         [project]
         name = "test-pkg"
         version = "1.0.0"
         {license_line}
-        authors = [
-            {{name = "Test Author", email = "test@example.com"}},
-        ]
         """
     )
+    if authors_block:
+        content += textwrap.dedent(authors_block)
     if extra:
         content += textwrap.dedent(extra)
     return content
@@ -93,6 +102,61 @@ def test_minimal_project_metadata(self, mock_setup, mock_exit):
             platforms=["GNU/Linux"],
         )
 
+    @patch("sys.exit")
+    @patch("setuptools.setup")
+    def test_no_authors(self, mock_setup, mock_exit):
+        with _project_dir(_minimal_pyproject(authors_block="")):
+            _run_setup_script()
+
+        mock_exit.assert_not_called()
+        mock_setup.assert_called_once_with(
+            name="test-pkg",
+            version="1.0.0",
+            platforms=["GNU/Linux"],
+        )
+
+    @patch("sys.exit")
+    @patch("setuptools.setup")
+    def test_author_name_only(self, mock_setup, mock_exit):
+        authors_block = textwrap.dedent(
+            """\
+            authors = [
+                {name = "Test Author"},
+            ]
+            """
+        )
+        with _project_dir(_minimal_pyproject(authors_block=authors_block)):
+            _run_setup_script()
+
+        mock_exit.assert_not_called()
+        mock_setup.assert_called_once_with(
+            name="test-pkg",
+            version="1.0.0",
+            author="Test Author",
+            platforms=["GNU/Linux"],
+        )
+
+    @patch("sys.exit")
+    @patch("setuptools.setup")
+    def test_author_email_only(self, mock_setup, mock_exit):
+        authors_block = textwrap.dedent(
+            """\
+            authors = [
+                {email = "test@example.com"},
+            ]
+            """
+        )
+        with _project_dir(_minimal_pyproject(authors_block=authors_block)):
+            _run_setup_script()
+
+        mock_exit.assert_not_called()
+        mock_setup.assert_called_once_with(
+            name="test-pkg",
+            version="1.0.0",
+            author_email="test@example.com",
+            platforms=["GNU/Linux"],
+        )
+
     @patch("sys.exit")
     @patch("setuptools.setup")
     def test_console_scripts_entry_points(self, mock_setup, mock_exit):