Allow using an empty string for the sources option to add a prefix …

…to distribution paths (#1064) * Allow using empty string to add prefixes to the distribution path Closes #802 * update example Co-Authored-By: Vincent Hatakeyama <[email protected]> * add release note Co-Authored-By: Vincent Hatakeyama <[email protected]> * fix lint Co-Authored-By: Vincent Hatakeyama <[email protected]> --------- Co-authored-by: Vincent Hatakeyama <[email protected]> Co-authored-by: Vincent Hatakeyama <[email protected]>
pypa · Nov 26, 2023 · feacd65 · feacd65
1 parent 0326e47
commit feacd65
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Showing 4 changed files with 22 additions and 12 deletions.
diff --git a/backend/src/hatchling/builders/config.py b/backend/src/hatchling/builders/config.py
@@ -675,11 +675,7 @@ def sources(self) -> dict[str, str]:
 
                     sources[normalize_relative_directory(source)] = ''
             elif isinstance(raw_sources, dict):
-                for i, (source, path) in enumerate(raw_sources.items(), 1):
-                    if not source:
-                        message = f'Source #{i} in field `{sources_location}` cannot be an empty string'
-                        raise ValueError(message)
-
+                for source, path in raw_sources.items():
                     if not isinstance(path, str):
                         message = f'Path for source `{source}` in field `{sources_location}` must be a string'
                         raise TypeError(message)
@@ -690,7 +686,7 @@ def sources(self) -> dict[str, str]:
                     else:
                         normalized_path += os.sep
 
-                    sources[normalize_relative_directory(source)] = normalized_path
+                    sources[normalize_relative_directory(source) if source else source] = normalized_path
             else:
                 message = f'Field `{sources_location}` must be a mapping or array of strings'
                 raise TypeError(message)
@@ -806,6 +802,9 @@ def only_include(self) -> dict[str, str]:
     def get_distribution_path(self, relative_path: str) -> str:
         # src/foo/bar.py -> foo/bar.py
         for source, replacement in self.sources.items():
+            if not source:
+                return replacement + relative_path
+
             if relative_path.startswith(source):
                 return relative_path.replace(source, replacement, 1)
 

diff --git a/docs/config/build.md b/docs/config/build.md
@@ -152,6 +152,15 @@ If you want to remove path prefixes entirely, rather than setting each to an emp
 sources = ["src"]
 ```
 
+If you want to add a prefix to paths, you can use an empty string. For example, the following configuration:
+
+```toml config-example
+[tool.hatch.build.sources]
+"" = "foo"
+```
+
+would distribute the file `bar/file.ext` as `foo/bar/file.ext`.
+
 The [packages](#packages) option itself relies on sources. Defining `#!toml packages = ["src/foo"]` for the `wheel` target is equivalent to the following:
 
 ```toml config-example

diff --git a/docs/history/hatchling.md b/docs/history/hatchling.md
@@ -16,6 +16,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - Fix parsing dependencies for environments when warnings are emitted
 - Properly handle non-zero version epoch for the `standard` version scheme
+- Allow using an empty string for the `sources` option to add a prefix to distribution paths
 
 ## [1.18.0](https://github.com/pypa/hatch/releases/tag/hatchling-v1.18.0) - 2023-06-12 ## {: #hatchling-v1.18.0 }
 

diff --git a/tests/backend/builders/test_config.py b/tests/backend/builders/test_config.py
@@ -684,8 +684,10 @@ def test_global_mapping_source_empty_string(self, isolation):
         config = {'tool': {'hatch': {'build': {'sources': {'': 'renamed'}}}}}
         builder = MockBuilder(str(isolation), config=config)
 
-        with pytest.raises(ValueError, match='Source #1 in field `tool.hatch.build.sources` cannot be an empty string'):
-            _ = builder.config.sources
+        assert len(builder.config.sources) == 1
+        assert builder.config.sources[''] == pjoin('renamed', '')
+        assert builder.config.get_distribution_path('bar.py') == pjoin('renamed', 'bar.py')
+        assert builder.config.get_distribution_path(pjoin('foo', 'bar.py')) == pjoin('renamed', 'foo', 'bar.py')
 
     def test_global_mapping_path_empty_string(self, isolation):
         config = {'tool': {'hatch': {'build': {'sources': {'src/foo': ''}}}}}
@@ -757,10 +759,9 @@ def test_target_mapping_source_empty_string(self, isolation):
         builder = MockBuilder(str(isolation), config=config)
         builder.PLUGIN_NAME = 'foo'
 
-        with pytest.raises(
-            ValueError, match='Source #1 in field `tool.hatch.build.targets.foo.sources` cannot be an empty string'
-        ):
-            _ = builder.config.sources
+        assert len(builder.config.sources) == 1
+        assert builder.config.sources[''] == pjoin('renamed', '')
+        assert builder.config.get_distribution_path(pjoin('bar.py')) == pjoin('renamed', 'bar.py')
 
     def test_target_mapping_path_empty_string(self, isolation):
         config = {'tool': {'hatch': {'build': {'targets': {'foo': {'sources': {'src/foo': ''}}}}}}}