Address comments and add directive

Update

Author: yushan8

CHANGELOG.md

@@ -72,6 +72,10 @@ END_UNRELEASED_TEMPLATE
 * (py_wheel) py_wheel always creates zip64-capable wheel zips
 * (providers) (experimental) {obj}`PyInfo.venv_symlinks` replaces
   `PyInfo.site_packages_symlinks`
+* (gazelle) For package mode, resolve dependencies when imports are relative
+  to the package path. This is enabled via the
+  `# gazelle:experimental_allow_relative_imports` true directive.
+  (https://github.com/bazel-contrib/rules_python/issues/2203)
 
 {#v0-0-0-fixed}
 ### Fixed

gazelle/README.md

@@ -121,12 +121,12 @@ gazelle_python_manifest(
     requirements = "//:requirements_lock.txt",
     # include_stub_packages: bool (default: False)
     # If set to True, this flag automatically includes any corresponding type stub packages
-    # for the third-party libraries that are present and used. For example, if you have 
+    # for the third-party libraries that are present and used. For example, if you have
     # `boto3` as a dependency, and this flag is enabled, the corresponding `boto3-stubs`
     # package will be automatically included in the BUILD file.
     #
-    # Enabling this feature helps ensure that type hints and stubs are readily available 
-    # for tools like type checkers and IDEs, improving the development experience and 
+    # Enabling this feature helps ensure that type hints and stubs are readily available
+    # for tools like type checkers and IDEs, improving the development experience and
     # reducing manual overhead in managing separate stub packages.
     include_stub_packages = True
 )
@@ -220,6 +220,8 @@ Python-specific directives are as follows:
 | Defines the format of the distribution name in labels to third-party deps. Useful for using Gazelle plugin with other rules with different repository conventions (e.g. `rules_pycross`). Full label is always prepended with (pip) repository name, e.g. `@pip//numpy`.                        |
 | `# gazelle:python_label_normalization`                                                                                                                                                                                                                                                          | `snake_case` |
 | Controls how distribution names in labels to third-party deps are normalized. Useful for using Gazelle plugin with other rules with different label conventions (e.g. `rules_pycross` uses PEP-503). Can be "snake_case", "none", or "pep503".                                                  |
+| `# gazelle:experimental_allow_relative_imports`          | `false` |
+| Controls whether Gazelle resolves dependencies for import statements that use paths relative to the current package. Can be "true" or "false".|
 
 #### Directive: `python_root`:
 
@@ -468,7 +470,7 @@ def py_test(name, main=None, **kwargs):
             name = "__test__",
             deps = ["@pip_pytest//:pkg"],  # change this to the pytest target in your repo.
         )
-    
+
         deps.append(":__test__")
         main = ":__test__.py"
 
@@ -581,6 +583,44 @@ deps = [
 ]
 ```
 
+#### Annotation: `experimental_allow_relative_imports`
+Enables experimental support for resolving relative imports in
+`python_generation_mode package`.
+
+By default, when `# gazelle:python_generation_mode package` is enabled,
+relative imports (e.g., from .library import foo) are not added to the
+deps field of the generated target. This results in incomplete py_library
+rules that lack required dependencies on sibling packages.
+
+Example:
+Given this Python file import:
+```python
+from .library import add as _add
+from .library import subtract as _subtract
+```
+
+Expected BUILD file output:
+```starlark
+py_library(
+    name = "py_default_library",
+    srcs = ["__init__.py"],
+    deps = [
+        "//example/library:py_default_library",
+    ],
+    visibility = ["//visibility:public"],
+)
+```
+
+Actual output without this annotation:
+```starlark
+py_library(
+    name = "py_default_library",
+    srcs = ["__init__.py"],
+    visibility = ["//visibility:public"],
+)
+```
+If the directive is set to `true`, gazelle will resolve imports
+that are relative to the current package.
 
 ### Libraries
 

gazelle/python/configure.go

@@ -68,6 +68,7 @@ func (py *Configurer) KnownDirectives() []string {
 		pythonconfig.TestFilePattern,
 		pythonconfig.LabelConvention,
 		pythonconfig.LabelNormalization,
+		pythonconfig.ExperimentalAllowRelativeImports,
 	}
 }
 
@@ -222,6 +223,13 @@ func (py *Configurer) Configure(c *config.Config, rel string, f *rule.File) {
 			default:
 				config.SetLabelNormalization(pythonconfig.DefaultLabelNormalizationType)
 			}
+		case pythonconfig.ExperimentalAllowRelativeImports:
+			v, err := strconv.ParseBool(strings.TrimSpace(d.Value))
+			if err != nil {
+				log.Printf("invalid value for gazelle:%s in %q: %q",
+					pythonconfig.ExperimentalAllowRelativeImports, rel, d.Value)
+			}
+			config.SetExperimentalAllowRelativeImports(v)
 		}
 	}
 

gazelle/python/resolve.go

@@ -71,7 +71,6 @@ func (py *Resolver) Imports(c *config.Config, r *rule.Rule, f *rule.File) []reso
 		}
 		pythonProjectRoot := cfg.PythonProjectRoot()
 		provide := importSpecFromSrc(pythonProjectRoot, f.Pkg, src)
-		// log.Printf("import to index: %v", provide.Imp)
 		provides = append(provides, provide)
 	}
 	if len(provides) == 0 {
@@ -158,18 +157,14 @@ func (py *Resolver) Resolve(
 			moduleName := mod.Name
 			// Transform relative imports `.` or `..foo.bar` into the package path from root.
 			if strings.HasPrefix(mod.From, ".") {
-				if !isPackageGeneration {
+				if !cfg.ExperimentalAllowRelativeImports() || !isPackageGeneration {
 					continue MODULES_LOOP
 				}
 
 				// Count number of leading dots in mod.From (e.g., ".." = 2, "...foo.bar" = 3)
-				relativeDepth := 0
-				for i := 0; i < len(mod.From); i++ {
-					if mod.From[i] == '.' {
-						relativeDepth++
-					} else {
-						break
-					}
+				relativeDepth := strings.IndexFunc(mod.From, func(r rune) bool { return r != '.' })
+				if relativeDepth == -1 {
+					relativeDepth = len(mod.From)
 				}
 
 				// Extract final symbol (e.g., "some_function") from mod.Name

gazelle/python/testdata/relative_imports_package_mode/BUILD.in

@@ -1 +1,2 @@
 # gazelle:python_generation_mode package
+# gazelle:experimental_allow_relative_imports true

gazelle/python/testdata/relative_imports_package_mode/BUILD.out

@@ -1,6 +1,7 @@
 load("@rules_python//python:defs.bzl", "py_binary")
 
 # gazelle:python_generation_mode package
+# gazelle:experimental_allow_relative_imports true
 
 py_binary(
     name = "relative_imports_package_mode_bin",

gazelle/python/testdata/relative_imports_package_mode/README.md

@@ -1,3 +1,6 @@
 # Resolve deps for relative imports
 
-This test case verifies that the generated targets correctly handle relative imports in Python. Specifically, when the Python generation mode is set to "package," it ensures that relative import statements such as from .foo import X are properly resolved to their corresponding modules.
+This test case verifies that the generated targets correctly handle relative imports in
+Python. Specifically, when the Python generation mode is set to "package," it ensures
+that relative import statements such as from .foo import X are properly resolved to
+their corresponding modules.

gazelle/python/testdata/relative_imports_package_mode/package1/subpackage1/subpackage2/script.py

@@ -1,6 +1,11 @@
-
-from ...my_library import some_function # Import path should be package1.my_library.some_function
-from ...my_library.foo import some_function # Import path should be package1.my_library.foo.some_function
-from .library import other_module # Import path should be package1.subpackage1.subpackage2.library.other_module
-from .. import some_module # Import path should be package1.subpackage1.some_module
-from .. import some_function # Import path should be package1.subpackage1.some_function
+from ...my_library import (
+    some_function,
+)  # Import path should be package1.my_library.some_function
+from ...my_library.foo import (
+    some_function,
+)  # Import path should be package1.my_library.foo.some_function
+from .library import (
+    other_module,
+)  # Import path should be package1.subpackage1.subpackage2.library.other_module
+from .. import some_module  # Import path should be package1.subpackage1.some_module
+from .. import some_function  # Import path should be package1.subpackage1.some_function

gazelle/python/testdata/relative_imports_project_mode/README.md

@@ -1,4 +1,5 @@
 # Relative imports
 
 This test case asserts that the generated targets handle relative imports in
-Python correctly. This tests that if python generation mode is project, the relative paths are included in the subdirectories.
+Python correctly. This tests that if python generation mode is project,
+the relative paths are included in the subdirectories.

gazelle/pythonconfig/pythonconfig.go

@@ -91,6 +91,9 @@ const (
 	// names of labels to third-party dependencies are normalized. Supported values
 	// are 'none', 'pep503' and 'snake_case' (default). See LabelNormalizationType.
 	LabelNormalization = "python_label_normalization"
+	// ExperimentalAllowRelativeImports represents the directive that controls
+	// whether relative imports are allowed.
+	ExperimentalAllowRelativeImports = "experimental_allow_relative_imports"
 )
 
 // GenerationModeType represents one of the generation modes for the Python
@@ -177,6 +180,7 @@ type Config struct {
 	testFilePattern                           []string
 	labelConvention                           string
 	labelNormalization                        LabelNormalizationType
+	experimentalAllowRelativeImports          bool
 }
 
 type LabelNormalizationType int
@@ -212,6 +216,7 @@ func New(
 		testFilePattern:                           strings.Split(DefaultTestFilePatternString, ","),
 		labelConvention:                           DefaultLabelConvention,
 		labelNormalization:                        DefaultLabelNormalizationType,
+		experimentalAllowRelativeImports:          false,
 	}
 }
 
@@ -244,6 +249,7 @@ func (c *Config) NewChild() *Config {
 		testFilePattern:                           c.testFilePattern,
 		labelConvention:                           c.labelConvention,
 		labelNormalization:                        c.labelNormalization,
+		experimentalAllowRelativeImports:          c.experimentalAllowRelativeImports,
 	}
 }
 
@@ -520,6 +526,16 @@ func (c *Config) LabelNormalization() LabelNormalizationType {
 	return c.labelNormalization
 }
 
+// SetExperimentalAllowRelativeImports sets whether relative imports are allowed.
+func (c *Config) SetExperimentalAllowRelativeImports(allowRelativeImports bool) {
+	c.experimentalAllowRelativeImports = allowRelativeImports
+}
+
+// ExperimentalAllowRelativeImports returns whether relative imports are allowed.
+func (c *Config) ExperimentalAllowRelativeImports() bool {
+	return c.experimentalAllowRelativeImports
+}
+
 // FormatThirdPartyDependency returns a label to a third-party dependency performing all formating and normalization.
 func (c *Config) FormatThirdPartyDependency(repositoryName string, distributionName string) label.Label {
 	conventionalDistributionName := strings.ReplaceAll(c.labelConvention, distributionNameLabelConventionSubstitution, distributionName)