[RFC] code location as a namedtuple

Author: RonnyPfannschmidt

src/_pytest/compat.py

@@ -11,6 +11,7 @@
 from typing import Any
 from typing import Callable
 from typing import Generic
+from typing import NamedTuple
 from typing import Optional
 from typing import Tuple
 from typing import TYPE_CHECKING
@@ -76,18 +77,35 @@ def is_async_function(func: object) -> bool:
     return iscoroutinefunction(func) or inspect.isasyncgenfunction(func)
 
 
-def getlocation(function, curdir: Optional[str] = None) -> str:
+class CodeLocation(NamedTuple):
+    path: Path
+    lineno: int
+
+
+def CodeLocation__str__(self: CodeLocation) -> str:
+    """Python 3.6 hack for NamedTuple __str__"""
+    return f"{self.path}:{self.lineno}"
+
+
+setattr(CodeLocation, "__str__", CodeLocation__str__)
+
+
+def getlocation(function, curdir: Optional[Path]) -> CodeLocation:
     function = get_real_func(function)
     fn = Path(inspect.getfile(function))
     lineno = function.__code__.co_firstlineno
+
+    # TODO: this cycle indicates a larger issue
+    from .pathlib import bestrelpath
+
     if curdir is not None:
         try:
-            relfn = fn.relative_to(curdir)
+            relfn = Path(bestrelpath(curdir, fn))
         except ValueError:
             pass
         else:
-            return "%s:%d" % (relfn, lineno + 1)
-    return "%s:%d" % (fn, lineno + 1)
+            return CodeLocation(relfn, lineno + 1)
+    return CodeLocation(fn, lineno + 1)
 
 
 def num_mock_patch_args(function) -> int:

src/_pytest/fixtures.py

@@ -660,7 +660,7 @@ def _compute_fixture_value(self, fixturedef: "FixtureDef[object]") -> None:
                     "\n\nRequested here:\n{}:{}".format(
                         funcitem.nodeid,
                         fixturedef.argname,
-                        getlocation(fixturedef.func, funcitem.config.rootdir),
+                        getlocation(fixturedef.func, funcitem.config.rootpath),
                         source_path_str,
                         source_lineno,
                     )
@@ -1202,7 +1202,7 @@ def __call__(self, function: _FixtureFunction) -> _FixtureFunction:
 
         name = self.name or function.__name__
         if name == "request":
-            location = getlocation(function)
+            location = getlocation(function, None)
             fail(
                 "'request' is a reserved word for fixtures, use another name:\n  {}".format(
                     location

src/_pytest/pathlib.py

@@ -32,7 +32,7 @@
 
 import py
 
-from _pytest.compat import assert_never
+from _pytest import compat
 from _pytest.outcomes import skip
 from _pytest.warning_types import PytestWarning
 
@@ -526,7 +526,7 @@ def import_path(
         if str(pkg_root) != sys.path[0]:
             sys.path.insert(0, str(pkg_root))
     else:
-        assert_never(mode)
+        compat.assert_never(mode)
 
     importlib.import_module(module_name)
 

src/_pytest/python.py

@@ -4,12 +4,14 @@
 import inspect
 import itertools
 import os
+import pathlib
 import sys
 import types
 import warnings
 from collections import Counter
 from collections import defaultdict
 from functools import partial
+from pathlib import Path
 from typing import Any
 from typing import Callable
 from typing import Dict
@@ -38,6 +40,7 @@
 from _pytest._io import TerminalWriter
 from _pytest._io.saferepr import saferepr
 from _pytest.compat import ascii_escaped
+from _pytest.compat import CodeLocation
 from _pytest.compat import final
 from _pytest.compat import get_default_arg_names
 from _pytest.compat import get_real_func
@@ -1405,13 +1408,12 @@ def _show_fixtures_per_test(config: Config, session: Session) -> None:
     import _pytest.config
 
     session.perform_collect()
-    curdir = py.path.local()
+    curdir = pathlib.Path.cwd()
     tw = _pytest.config.create_terminal_writer(config)
     verbose = config.getvalue("verbose")
 
     def get_best_relpath(func):
-        loc = getlocation(func, str(curdir))
-        return curdir.bestrelpath(py.path.local(loc))
+        return getlocation(func, curdir)
 
     def write_fixture(fixture_def: fixtures.FixtureDef[object]) -> None:
         argname = fixture_def.argname
@@ -1461,29 +1463,29 @@ def _showfixtures_main(config: Config, session: Session) -> None:
     import _pytest.config
 
     session.perform_collect()
-    curdir = py.path.local()
+    curdir = Path.cwd()
     tw = _pytest.config.create_terminal_writer(config)
     verbose = config.getvalue("verbose")
 
     fm = session._fixturemanager
 
     available = []
-    seen: Set[Tuple[str, str]] = set()
+    seen: Set[Tuple[str, CodeLocation]] = set()
 
     for argname, fixturedefs in fm._arg2fixturedefs.items():
         assert fixturedefs is not None
         if not fixturedefs:
             continue
         for fixturedef in fixturedefs:
-            loc = getlocation(fixturedef.func, str(curdir))
+            loc = getlocation(fixturedef.func, curdir)
             if (fixturedef.argname, loc) in seen:
                 continue
             seen.add((fixturedef.argname, loc))
             available.append(
                 (
                     len(fixturedef.baseid),
                     fixturedef.func.__module__,
-                    curdir.bestrelpath(py.path.local(loc)),
+                    loc,
                     fixturedef.argname,
                     fixturedef,
                 )
@@ -1503,9 +1505,9 @@ def _showfixtures_main(config: Config, session: Session) -> None:
         if fixturedef.scope != "function":
             tw.write(" [%s scope]" % fixturedef.scope, cyan=True)
         if verbose > 0:
-            tw.write(" -- %s" % bestrel, yellow=True)
+            tw.write(" -- %s" % str(bestrel), yellow=True)
         tw.write("\n")
-        loc = getlocation(fixturedef.func, str(curdir))
+        loc = getlocation(fixturedef.func, curdir)
         doc = inspect.getdoc(fixturedef.func)
         if doc:
             write_docstring(tw, doc)