Minor tweaks to warning and error messages.

changes/1812.feature.rst

@@ -1 +1 @@
-The name of the LICENSE file can now be specified in the PEP621-section of the pyproject.toml file
+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/config.py

@@ -560,12 +560,12 @@ def parse_config(config_file, platform, output_format, logger):
         if isinstance(config.get("license"), str):
             config["license"] = {"file": "LICENSE"}
             old_license_format = True
+
     if old_license_format:
         logger.warning(
-            "The license was specified using a string, however Briefcase prefers a PEP621 "
-            "compatible dictionary on the form {'file': '{filename}'} or {'text': '{license_text}'}.\n"
-            "Therefore, when given the license as a string, Briefcase ignores the license string and "
-            "defaults to {'file': 'LICENSE'}."
+            "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

@@ -711,28 +711,31 @@ def build_app(self, app: AppConfig, **kwargs):
                 else:
                     raise BriefcaseCommandError(
                         f"""\
-You specified that the license file is {license_file}. However, this file does not exist.
+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.
 
-Make sure you spelled the name of the license file correctly in `pyproject.toml`.
 """
                     )
             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(
                         """
-You specified the license using a text string. However, this string is only one line.
-
-Make sure that the license text is a full license (or specify a license file).
+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.
 """
                 )
 
@@ -811,7 +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.
 

tests/commands/convert/test_migrate_necessary_files.py

@@ -143,6 +143,34 @@ def test_pep621_specified_license_filename(
     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 not found in '{convert_command.base_path}'. "
+        "Briefcase will create a template 'LICENSE' file."
+    )
+
+
 @pytest.mark.parametrize("test_source_dir", ["tests"])
 def test_warning_without_changelog_file(
     convert_command,

tests/config/test_parse_config.py

@@ -13,7 +13,10 @@ def test_invalid_toml():
 
     with pytest.raises(BriefcaseConfigError, match="Invalid pyproject.toml"):
         parse_config(
-            config_file, platform="macOS", output_format="Xcode", logger=Mock()
+            config_file,
+            platform="macOS",
+            output_format="Xcode",
+            logger=Mock(),
         )
 
 
@@ -29,7 +32,10 @@ def test_no_briefcase_section():
 
     with pytest.raises(BriefcaseConfigError, match="No tool.briefcase section"):
         parse_config(
-            config_file, platform="macOS", output_format="Xcode", logger=Mock()
+            config_file,
+            platform="macOS",
+            output_format="Xcode",
+            logger=Mock(),
         )
 
 
@@ -45,7 +51,10 @@ def test_no_apps():
 
     with pytest.raises(BriefcaseConfigError, match="No Briefcase apps defined"):
         parse_config(
-            config_file, platform="macOS", output_format="Xcode", logger=Mock()
+            config_file,
+            platform="macOS",
+            output_format="Xcode",
+            logger=Mock(),
         )
 
 
@@ -62,7 +71,10 @@ def test_single_minimal_app():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # There's a single global option
@@ -71,7 +83,11 @@ def test_single_minimal_app():
     # The app gets the name from its header line.
     # It inherits the value from the base definition.
     assert apps == {
-        "my_app": {"app_name": "my_app", "value": 42, "license": {"file": "LICENSE"}}
+        "my_app": {
+            "app_name": "my_app",
+            "value": 42,
+            "license": {"file": "LICENSE"},
+        }
     }
 
 
@@ -91,7 +107,10 @@ def test_multiple_minimal_apps():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # There are no global options
@@ -137,7 +156,10 @@ def test_platform_override():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -200,7 +222,10 @@ def test_platform_override_ordering():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -279,7 +304,10 @@ def test_format_override():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="app", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="app",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -359,7 +387,10 @@ def test_format_override_ordering():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="app", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="app",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -427,7 +458,10 @@ def test_requires():
 
     # Request a macOS app
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="app", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="app",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -464,7 +498,10 @@ def test_requires():
     # Request a macOS xcode project
     config_file.seek(0)
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -500,7 +537,10 @@ def test_requires():
 
     config_file.seek(0)
     global_options, apps = parse_config(
-        config_file, platform="linux", output_format="appimage", logger=Mock()
+        config_file,
+        platform="linux",
+        output_format="appimage",
+        logger=Mock(),
     )
 
     # The global options are exactly as specified
@@ -561,7 +601,10 @@ def test_document_types():
 
     # Request a macOS app
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="Xcode", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="Xcode",
+        logger=Mock(),
     )
 
     # The macOS my_app app specifies a full inherited chain.
@@ -632,7 +675,10 @@ def test_pep621_defaults():
     )
 
     global_options, apps = parse_config(
-        config_file, platform="macOS", output_format="app", logger=Mock()
+        config_file,
+        platform="macOS",
+        output_format="app",
+        logger=Mock(),
     )
 
     awesome = apps["awesome"]
@@ -683,8 +729,7 @@ def test_license_is_string():
         "license": {"file": "LICENSE"},
     }
     logger.warning.assert_called_once_with(
-        "The license was specified using a string, however Briefcase prefers a PEP621 "
-        "compatible dictionary on the form {'file': '{filename}'} or {'text': '{license_text}'}.\n"
-        "Therefore, when given the license as a string, Briefcase ignores the license string and "
-        "defaults to {'file': 'LICENSE'}."
+        "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".'
     )

tests/platforms/linux/system/test_build.py

@@ -118,7 +118,7 @@ def test_missing_license(build_command, first_app, tmp_path):
     # Build the app; it will fail
     with pytest.raises(
         BriefcaseCommandError,
-        match=r"You specified that the license file is ",
+        match=r"Your `pyproject.toml` specifies a license file of 'LICENSE'",
     ):
         build_command.build_app(first_app)
 
@@ -183,22 +183,23 @@ def test_license_text_warns_with_single_line_license(build_command, first_app):
 
     build_command.logger.warning.assert_called_once_with(
         """
-You specified the license using a text string. However, this string is only one line.
-
-Make sure that the license text is a full license (or specify a license file).
+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.
 """
     )
 
 
 def test_exception_with_no_license(build_command, first_app):
-    """An exception is raised if there is no license."""
+    """An exception is raised if there is no license defined."""
 
     first_app.license = {}
     build_command.logger.warning = mock.MagicMock()
 
     # Build the app
     with pytest.raises(
-        BriefcaseCommandError, match="Your project does not contain a LICENSE file."
+        BriefcaseCommandError,
+        match="Your project does not contain a LICENSE definition.",
     ):
         build_command.build_app(first_app)