Support specifying the license file in the pyproject.toml file

changes/1812.feature.rst

@@ -0,0 +1 @@
+The name of the license file can now be specified using a PEP 621-compliant format for the ``license`` setting.

changes/1812.removal.rst

@@ -0,0 +1 @@
+The format for the ``license`` field has been converted to PEP 621 format. Existing projects that specify ``license`` as a string should update their configurations to point at the generated license file using ``license.file = "LICENSE"``.

src/briefcase/commands/base.py

@@ -831,6 +831,7 @@ def parse_config(self, filename, overrides):
                     config_file,
                     platform=self.platform,
                     output_format=self.output_format,
+                    logger=self.logger,
                 )
 
                 # Create the global config

src/briefcase/commands/convert.py

@@ -647,16 +647,8 @@ def migrate_necessary_files(self, project_dir, test_source_dir, module_name):
 
         # Copy license file if not already there
         license_file = self.pep621_data.get("license", {}).get("file")
-        if license_file is not None and Path(license_file).name != "LICENSE":
-            self.logger.warning(
-                f"\nLicense file found in '{self.base_path}', but its name is "
-                f"'{Path(license_file).name}', not 'LICENSE'. Briefcase will create a "
-                "template 'LICENSE' file, but you might want to consider renaming the "
-                "existing file."
-            )
-            copy2(project_dir / "LICENSE", self.base_path / "LICENSE")
 
-        elif not (self.base_path / "LICENSE").exists():
+        if license_file is None and not (self.base_path / "LICENSE").exists():
             self.logger.warning(
                 f"\nLicense file not found in '{self.base_path}'. "
                 "Briefcase will create a template 'LICENSE' file."

src/briefcase/config.py

@@ -154,6 +154,7 @@ def __init__(
         project_name,
         version,
         bundle,
+        license=None,
         url=None,
         author=None,
         author_email=None,
@@ -166,6 +167,7 @@ def __init__(
         self.url = url
         self.author = author
         self.author_email = author_email
+        self.license = license
 
         # Version number is PEP440 compliant:
         if not is_pep440_canonical_version(self.version):
@@ -187,6 +189,7 @@ def __init__(
         bundle,
         description,
         sources,
+        license,
         formal_name=None,
         url=None,
         author=None,
@@ -228,6 +231,7 @@ def __init__(
         self.test_requires = test_requires
         self.supported = supported
         self.long_description = long_description
+        self.license = license
 
         if not is_valid_app_name(self.app_name):
             raise BriefcaseConfigError(
@@ -393,7 +397,7 @@ def maybe_update(field, *project_fields):
 
     # Keys that map directly
     maybe_update("description", "description")
-    maybe_update("license", "license", "text")
+    maybe_update("license", "license")
     maybe_update("url", "urls", "Homepage")
     maybe_update("version", "version")
 
@@ -426,7 +430,7 @@ def maybe_update(field, *project_fields):
         pass
 
 
-def parse_config(config_file, platform, output_format):
+def parse_config(config_file, platform, output_format, logger):
     """Parse the briefcase section of the pyproject.toml configuration file.
 
     This method only does basic structural parsing of the TOML, looking for,
@@ -551,4 +555,17 @@ def parse_config(config_file, platform, output_format):
         # of configurations that are being handled.
         app_configs[app_name] = config
 
+    old_license_format = False
+    for config in [global_config, *app_configs.values()]:
+        if isinstance(config.get("license"), str):
+            config["license"] = {"file": "LICENSE"}
+            old_license_format = True
+
+    if old_license_format:
+        logger.warning(
+            "Your app configuration has a `license` field that is specified as a string. "
+            "Briefcase now uses PEP 621 format for license definitions. To silence this "
+            'warning, replace the `license` declaration with `license.file = "LICENSE".'
+        )
+
     return global_config, app_configs

src/briefcase/platforms/linux/system.py

@@ -704,16 +704,38 @@ def build_app(self, app: AppConfig, **kwargs):
         doc_folder.mkdir(parents=True, exist_ok=True)
 
         with self.input.wait_bar("Installing license..."):
-            license_file = self.base_path / "LICENSE"
-            if license_file.is_file():
-                self.tools.shutil.copy(license_file, doc_folder / "copyright")
+            if license_file := app.license.get("file"):
+                license_file = self.base_path / license_file
+                if license_file.is_file():
+                    self.tools.shutil.copy(license_file, doc_folder / "copyright")
+                else:
+                    raise BriefcaseCommandError(
+                        f"""\
+Your `pyproject.toml` specifies a license file of {str(license_file.relative_to(self.base_path))!r}.
+However, this file does not exist.
+
+Ensure you have correctly spelled the filename in your `license.file` setting.
+
+"""
+                    )
+            elif license_text := app.license.get("text"):
+                (doc_folder / "copyright").write_text(license_text, encoding="utf-8")
+                if len(license_text.splitlines()) <= 1:
+                    self.logger.warning(
+                        """
+Your app specifies a license using `license.text`, but the value doesn't appear to be a
+full license. Briefcase will generate a `copyright` file for your project; you should
+ensure that the contents of this file is adequate.
+"""
+                    )
             else:
                 raise BriefcaseCommandError(
                     """\
-Your project does not contain a LICENSE file.
+Your project does not contain a LICENSE definition.
 
 Create a file named `LICENSE` in the same directory as your `pyproject.toml`
-with your app's licensing terms.
+with your app's licensing terms, and set `license.file = 'LICENSE'` in your
+app's configuration.
 """
                 )
 
@@ -792,7 +814,11 @@ class LinuxSystemRunCommand(LinuxSystemMixin, RunCommand):
     supported_host_os_reason = "Linux system projects can only be executed on Linux."
 
     def run_app(
-        self, app: AppConfig, test_mode: bool, passthrough: list[str], **kwargs
+        self,
+        app: AppConfig,
+        test_mode: bool,
+        passthrough: list[str],
+        **kwargs,
     ):
         """Start the application.
 
@@ -1037,7 +1063,7 @@ def _package_rpm(self, app: AppConfig, **kwargs):  # pragma: no-cover-if-is-wind
                             f"Release:        {getattr(app, 'revision', 1)}%{{?dist}}",
                             f"Summary:        {app.description}",
                             "",
-                            f"License:        {getattr(app, 'license', 'Unknown')}",
+                            "License:        Unknown",  # TODO: Add license information (see #1829)
                             f"URL:            {app.url}",
                             "Source0:        %{name}-%{version}.tar.gz",
                             "",
@@ -1196,7 +1222,7 @@ def _package_pkg(self, app: AppConfig, **kwargs):  # pragma: no-cover-if-is-wind
                             f'pkgdesc="{app.description}"',
                             f"arch=('{self.pkg_abi(app)}')",
                             f'url="{app.url}"',
-                            f"license=('{app.license}')",
+                            "license=('Unknown')",
                             f"depends=({system_runtime_requires})",
                             "changelog=CHANGELOG",
                             'source=("$pkgname-$pkgver.tar.gz")',

tests/commands/base/conftest.py

@@ -114,4 +114,5 @@ def my_app():
         version="1.2.3",
         description="This is a simple app",
         sources=["src/my_app"],
+        license={"file": "LICENSE"},
     )

tests/commands/base/test_finalize.py

@@ -13,6 +13,7 @@ def first_app():
         version="0.0.1",
         description="The first simple app",
         sources=["src/first"],
+        license={"file": "LICENSE"},
     )
 
 
@@ -24,6 +25,7 @@ def second_app():
         version="0.0.2",
         description="The second simple app",
         sources=["src/second"],
+        license={"file": "LICENSE"},
     )
 
 

tests/commands/base/test_parse_config.py

@@ -23,6 +23,7 @@ def test_incomplete_global_config(base_command):
         [tool.briefcase]
         version = "1.2.3"
         description = "A sample app"
+        license.file = "LICENSE"
 
         [tool.briefcase.app.my-app]
     """,
@@ -47,6 +48,7 @@ def test_incomplete_config(base_command):
         version = "1.2.3"
         bundle = "com.example"
         description = "A sample app"
+        license.file = "LICENSE"
 
         [tool.briefcase.app.my-app]
     """,
@@ -71,6 +73,7 @@ def test_parse_config(base_command):
         description = "A sample app"
         bundle = "org.beeware"
         mystery = 'default'
+        license.file = "LICENSE"
 
         [tool.briefcase.app.firstapp]
         sources = ['src/firstapp']
@@ -127,6 +130,7 @@ def test_parse_config_with_overrides(base_command):
         description = "A sample app"
         bundle = "org.beeware"
         mystery = 'default'
+        license.file = "LICENSE"
 
         [tool.briefcase.app.firstapp]
         sources = ['src/firstapp']
@@ -197,6 +201,7 @@ def test_parse_config_with_invalid_override(base_command):
         description = "A sample app"
         bundle = "org.beeware"
         mystery = 'default'
+        license.file = "LICENSE"
 
         [tool.briefcase.app.firstapp]
         sources = ['src/firstapp']

tests/commands/build/conftest.py

@@ -95,6 +95,7 @@ def second_app_config():
         version="0.0.2",
         description="The second simple app",
         sources=["src/second"],
+        license={"file": "LICENSE"},
     )
 
 

tests/commands/convert/test_migrate_necessary_files.py

@@ -102,12 +102,31 @@ def test_warning_without_license_file(
 
 
 @pytest.mark.parametrize("test_source_dir", ["tests"])
-def test_pep621_wrong_license_filename(
+def test_file_is_copied_if_no_license_file_specified(
     convert_command,
     project_dir_with_files,
     dummy_app_name,
     test_source_dir,
 ):
+    """A license file is copied if no license file is specified in pyproject.toml."""
+    create_file(convert_command.base_path / "CHANGELOG", "")
+    assert not (convert_command.base_path / "LICENSE").exists()
+    convert_command.migrate_necessary_files(
+        project_dir_with_files,
+        test_source_dir,
+        dummy_app_name,
+    )
+    assert (convert_command.base_path / "LICENSE").exists()
+
+
+@pytest.mark.parametrize("test_source_dir", ["tests"])
+def test_pep621_specified_license_filename(
+    convert_command,
+    project_dir_with_files,
+    dummy_app_name,
+    test_source_dir,
+):
+    """No license file is copied if a license file is specified in pyproject.toml."""
     convert_command.logger.warning = mock.MagicMock()
     license_name = "LICENSE.txt"
     create_file(convert_command.base_path / license_name, "")
@@ -121,10 +140,34 @@ def test_pep621_wrong_license_filename(
         test_source_dir,
         dummy_app_name,
     )
+    assert not (convert_command.base_path / "LICENSE").exists()
+
+
+@pytest.mark.parametrize("test_source_dir", ["tests"])
+def test_pep621_specified_license_text(
+    convert_command,
+    project_dir_with_files,
+    dummy_app_name,
+    test_source_dir,
+):
+    """A license file is copied if the license is specified as text and no LICENSE file
+    exists."""
+    convert_command.logger.warning = mock.MagicMock()
+    create_file(
+        convert_command.base_path / "pyproject.toml",
+        '[project]\nlicense = { text = "New BSD" }',
+    )
+    create_file(convert_command.base_path / "CHANGELOG", "")
+    convert_command.migrate_necessary_files(
+        project_dir_with_files,
+        test_source_dir,
+        dummy_app_name,
+    )
+    assert (convert_command.base_path / "LICENSE").exists()
+
     convert_command.logger.warning.assert_called_once_with(
-        f"\nLicense file found in '{convert_command.base_path}', but its name is "
-        f"'{license_name}', not 'LICENSE'. Briefcase will create a template 'LICENSE' "
-        "file, but you might want to consider renaming the existing file."
+        f"\nLicense file not found in '{convert_command.base_path}'. "
+        "Briefcase will create a template 'LICENSE' file."
     )
 
 
@@ -162,7 +205,11 @@ def test_no_warning_with_license_and_changelog_file(
     """No warning is raised if both license file and changelog file is present."""
     convert_command.logger.warning = mock.MagicMock()
 
-    create_file(convert_command.base_path / "LICENSE", "")
+    create_file(
+        convert_command.base_path / "pyproject.toml",
+        '[project]\nlicense = { file = "LICENSE.txt" }',
+    )
+    create_file(convert_command.base_path / "LICENSE.txt", "")
     create_file(convert_command.base_path / "CHANGELOG", "")
     convert_command.migrate_necessary_files(
         project_dir_with_files,

tests/commands/create/conftest.py

@@ -199,13 +199,15 @@ def tracking_create_command(tmp_path, mock_git, monkeypatch_tool_host_os):
                 version="0.0.1",
                 description="The first simple app",
                 sources=["src/first"],
+                license={"file": "LICENSE"},
             ),
             "second": AppConfig(
                 app_name="second",
                 bundle="com.example",
                 version="0.0.2",
                 description="The second simple app",
                 sources=["src/second"],
+                license={"file": "LICENSE"},
             ),
         },
     )
@@ -223,6 +225,7 @@ def myapp():
         url="https://example.com",
         author="First Last",
         author_email="first@example.com",
+        license={"file": "LICENSE"},
     )
 
 

tests/commands/create/test_create_app.py

@@ -155,6 +155,7 @@ def test_create_app_not_supported(tracking_create_command, tmp_path):
                 description="The third simple app",
                 sources=["src/third"],
                 supported=False,
+                license={"file": "LICENSE"},
             )
         )
 

tests/commands/create/test_generate_app_template.py

@@ -41,6 +41,7 @@ def full_context():
         "custom_permissions": {},
         "requests": {},
         "document_types": {},
+        "license": {"file": "LICENSE"},
         # Properties of the generating environment
         "python_version": platform.python_version(),
         "host_arch": "gothic",