Add basic Goto Implementation Request support

CONFIGURATION.md

@@ -72,6 +72,7 @@ This server can be configured using the `workspace/didChangeConfiguration` metho
 | `pylsp.plugins.rope_autoimport.memory` | `boolean` | Make the autoimport database memory only. Drastically increases startup time. | `false` |
 | `pylsp.plugins.rope_completion.enabled` | `boolean` | Enable or disable the plugin. | `false` |
 | `pylsp.plugins.rope_completion.eager` | `boolean` | Resolve documentation and detail eagerly. | `false` |
+| `pylsp.plugins.rope_implementation.enabled` | `boolean` | Enable or disable the plugin. | `true` |
 | `pylsp.plugins.yapf.enabled` | `boolean` | Enable or disable the plugin. | `true` |
 | `pylsp.rope.extensionModules` | `string` | Builtin and c-extension modules that are allowed to be imported and inspected by rope. | `null` |
 | `pylsp.rope.ropeFolder` | `array` of unique `string` items | The name of the folder in which rope stores project configurations and data. Pass `null` for not using such a folder at all. | `null` |

README.md

@@ -15,7 +15,7 @@ pip install python-lsp-server
 This will expose the command `pylsp` on your PATH. Confirm that installation succeeded by running `pylsp --help`.
 
 If the respective dependencies are found, the following optional providers will be enabled:
-- [Rope](https://github.com/python-rope/rope) for Completions and renaming
+- [Rope](https://github.com/python-rope/rope) for Completions, Goto Implementation, and renaming
 - [Pyflakes](https://github.com/PyCQA/pyflakes) linter to detect various errors
 - [McCabe](https://github.com/PyCQA/mccabe) linter for complexity checking
 - [pycodestyle](https://github.com/PyCQA/pycodestyle) linter for style checking
@@ -151,7 +151,7 @@ pip install 'python-lsp-server[websockets]'
 * Code Linting
 * Code actions
 * Signature Help
-* Go to definition
+* Go to definition or implementation
 * Hover
 * Find References
 * Document Symbols

pylsp/config/schema.json

@@ -487,6 +487,11 @@
  "default": false,
  "description": "Resolve documentation and detail eagerly."
  },
+ "pylsp.plugins.rope_implementation.enabled": {
+ "type": "boolean",
+ "default": true,
+ "description": "Enable or disable the plugin."
+ },
  "pylsp.plugins.yapf.enabled": {
  "type": "boolean",
  "default": true,

pylsp/hookspecs.py

@@ -93,6 +93,11 @@ def pylsp_hover(config, workspace, document, position) -> None:
  pass
 
 
+@hookspec
+def pylsp_implementations(config, workspace, document, position) -> None:
+ pass
+
+
 @hookspec
 def pylsp_initialize(config, workspace) -> None:
  pass

pylsp/plugins/rope_implementation.py

@@ -0,0 +1,74 @@
+# Copyright 2017-2020 Palantir Technologies, Inc.
+# Copyright 2021- Python Language Server Contributors.
+import logging
+import os
+from typing import Any, Dict, Tuple
+
+from rope.base.project import Project
+from rope.base.resources import Resource
+from rope.contrib.findit import Location, find_implementations
+
+from pylsp import hookimpl, uris
+
+log = logging.getLogger(__name__)
+
+
+@hookimpl
+def pylsp_settings():
+ # Default to enabled (no reason not to)
+ return {"plugins": {"rope_implementation": {"enabled": True}}}
+
+
+@hookimpl
+def pylsp_implementations(config, workspace, document, position):
+ offset = document.offset_at_position(position)
+ rope_config = config.settings(document_path=document.path).get("rope", {})
+ rope_project = workspace._rope_project_builder(rope_config)
+ rope_resource = document._rope_resource(rope_config)
+
+ try:
+ impls = find_implementations(rope_project, rope_resource, offset)
+ except Exception as e:
+ log.debug("Failed to run Rope implementations finder: %s", e)
+ return []
+
+ return [
+ {
+ "uri": uris.uri_with(
+ document.uri,
+ path=os.path.join(workspace.root_path, impl.resource.path),
+ ),
+ "range": _rope_location_to_range(impl, rope_project),
+ }
+ for impl in impls
+ ]
+
+
+def _rope_location_to_range(
+ location: Location, rope_project: Project
+) -> Dict[str, Any]:
+ # NOTE: This assumes the result is confined to a single line, which should
+ # always be the case here because Python doesn't allow splitting up
+ # identifiers across more than one line.
+ start_column, end_column = _rope_region_to_columns(
+ location.region, location.lineno, location.resource, rope_project
+ )
+ return {
+ "start": {"line": location.lineno - 1, "character": start_column},
+ "end": {"line": location.lineno - 1, "character": end_column},
+ }
+
+
+def _rope_region_to_columns(
+ offsets: Tuple[int, int], line: int, rope_resource: Resource, rope_project: Project
+) -> Tuple[int, int]:
+ """
+ Convert pair of offsets from start of file to columns within line.
+
+ Assumes both offsets reside within the same line and will return nonsense
+ for the end offset if this isn't the case.
+ """
+ line_start_offset = rope_project.get_pymodule(rope_resource).lines.get_line_start(
+ line
+ )
+ return offsets[0] - line_start_offset, offsets[1] - line_start_offset

pylsp/python_lsp.py

@@ -280,6 +280,7 @@ def capabilities(self):
  "commands": flatten(self._hook("pylsp_commands"))
  },
  "hoverProvider": True,
+ "implementationProvider": True, # only when Rope is installed
  "referencesProvider": True,
  "renameProvider": True,
  "foldingRangeProvider": True,
@@ -436,6 +437,9 @@ def highlight(self, doc_uri, position):
  def hover(self, doc_uri, position):
  return self._hook("pylsp_hover", doc_uri, position=position) or {"contents": ""}
 
+ def implementations(self, doc_uri, position):
+ return flatten(self._hook("pylsp_implementations", doc_uri, position=position))
+
  @_utils.debounce(LINT_DEBOUNCE_S, keyed_by="doc_uri")
  def lint(self, doc_uri, is_saved) -> None:
  # Since we're debounced, the document may no longer be open
@@ -762,6 +766,10 @@ def m_text_document__definition(self, textDocument=None, position=None, **_kwarg
  return self._cell_document__definition(document, position, **_kwargs)
  return self.definitions(textDocument["uri"], position)
 
+ def m_text_document__implementation(self, textDocument=None, position=None, **_kwargs):
+ # textDocument here is just a dict with a uri
+ return self.implementations(textDocument["uri"], position)
+
  def m_text_document__document_highlight(
  self, textDocument=None, position=None, **_kwargs
  ):

pyproject.toml

@@ -80,6 +80,7 @@ pyflakes = "pylsp.plugins.pyflakes_lint"
 pylint = "pylsp.plugins.pylint_lint"
 rope_completion = "pylsp.plugins.rope_completion"
 rope_autoimport = "pylsp.plugins.rope_autoimport"
+rope_implementation = "pylsp.plugins.rope_implementation"
 yapf = "pylsp.plugins.yapf_format"
 
 [project.scripts]

test/data/implementations_examples/example.py

@@ -0,0 +1,30 @@
+from abc import ABC, abstractmethod
+
+
+class Animal(ABC):
+ @abstractmethod
+ def breathe(self):
+ pass
+
+ @property
+ @abstractmethod
+ def size(self) -> str:
+ pass
+
+class WingedAnimal(Animal):
+ @abstractmethod
+ def fly(self, destination):
+ pass
+
+class Bird(WingedAnimal):
+ def breathe(self):
+ print("*inhales like a bird*")
+
+ def fly(self, destination):
+ print("*flies like a bird*")
+
+ @property
+ def size(self) -> str:
+ return "bird-sized"
+
+print("not a method at all")

test/plugins/test_implementations.py

@@ -0,0 +1,102 @@
+# Copyright 2017-2020 Palantir Technologies, Inc.
+# Copyright 2021- Python Language Server Contributors.
+
+from pathlib import Path
+
+import pytest
+
+import test
+from pylsp import uris
+from pylsp.config.config import Config
+from pylsp.plugins.rope_implementation import pylsp_implementations
+from pylsp.workspace import Workspace
+
+
+# We use a real file because the part of Rope that this feature uses
+# (`rope.findit.find_implementations`) *always* loads files from the
+# filesystem, in contrast to e.g. `code_assist` which takes a `source` argument
+# that can be more easily faked.
+# An alternative to using real files would be `unittest.mock.patch`, but that
+# ends up being more trouble than it's worth...
+@pytest.fixture
+def examples_dir_path() -> Path:
+ # In Python 3.12+, this should be obtained using `importlib.resources`,
+ # but as we need to support older versions, we do it the hacky way:
+ return Path(test.__file__).parent / "data/implementations_examples"
+
+
+@pytest.fixture
+def doc_uri(examples_dir_path: Path) -> str:
+ return uris.from_fs_path(str(examples_dir_path / "example.py"))
+
+
+# Similarly to the above, we need our workspace to point to the actual location
+# on the filesystem containing the example modules, so we override the fixture:
+@pytest.fixture
+def workspace(examples_dir_path: Path, endpoint) -> None:
+ ws = Workspace(uris.from_fs_path(str(examples_dir_path)), endpoint)
+ ws._config = Config(ws.root_uri, {}, 0, {})
+ yield ws
+ ws.close()
+
+
+def test_implementations(config, workspace, doc_uri) -> None:
+ # Over 'fly' in WingedAnimal.fly
+ cursor_pos = {"line": 15, "character": 8}
+
+ # The implementation of 'Bird.fly'
+ def_range = {
+ "start": {"line": 22, "character": 8},
+ "end": {"line": 22, "character": 11},
+ }
+
+ doc = workspace.get_document(doc_uri)
+ assert [{"uri": doc_uri, "range": def_range}] == pylsp_implementations(
+ config, workspace, doc, cursor_pos
+ )
+
+
+def test_implementations_skipping_one_class(config, workspace, doc_uri) -> None:
+ # Over 'Animal.breathe'
+ cursor_pos = {"line": 5, "character": 8}
+
+ # The implementation of 'breathe', skipping intermediate classes
+ def_range = {
+ "start": {"line": 19, "character": 8},
+ "end": {"line": 19, "character": 15},
+ }
+
+ doc = workspace.get_document(doc_uri)
+ assert [{"uri": doc_uri, "range": def_range}] == pylsp_implementations(
+ config, workspace, doc, cursor_pos
+ )
+
+
+@pytest.mark.xfail(
+ reason="not implemented upstream (Rope)", strict=True, raises=AssertionError
+)
+def test_property_implementations(config, workspace, doc_uri) -> None:
+ # Over 'Animal.size'
+ cursor_pos = {"line": 10, "character": 9}
+
+ # The property implementation 'Bird.size'
+ def_range = {
+ "start": {"line": 26, "character": 8},
+ "end": {"line": 26, "character": 12},
+ }
+
+ doc = workspace.get_document(doc_uri)
+ assert [{"uri": doc_uri, "range": def_range}] == pylsp_implementations(
+ config, workspace, doc, cursor_pos
+ )
+
+
+def test_implementations_not_a_method(config, workspace, doc_uri) -> None:
+ # Over 'print(...)' call
+ cursor_pos = {"line": 29, "character": 0}
+
+ doc = workspace.get_document(doc_uri)
+
+ # Rope produces an error because we're not over a method, which we then
+ # turn into an empty result list:
+ assert [] == pylsp_implementations(config, workspace, doc, cursor_pos)