[refactor] Create a file for set comparison in assertion

Author: Pierre-Sassoulas

src/_pytest/assertion/_compare_set.py

@@ -0,0 +1,77 @@
+from __future__ import annotations
+
+from collections.abc import Callable
+from collections.abc import Set as AbstractSet
+from typing import Any
+
+from _pytest._io.saferepr import saferepr
+from _pytest.assertion._typing import _HighlightFunc
+
+
+def _set_one_sided_diff(
+    posn: str,
+    set1: AbstractSet[Any],
+    set2: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+) -> list[str]:
+    explanation = []
+    diff = set1 - set2
+    if diff:
+        explanation.append(f"Extra items in the {posn} set:")
+        for item in diff:
+            explanation.append(highlighter(saferepr(item)))
+    return explanation
+
+
+def _compare_eq_set(
+    left: AbstractSet[Any],
+    right: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+    verbose: int = 0,
+) -> list[str]:
+    explanation = []
+    explanation.extend(_set_one_sided_diff("left", left, right, highlighter))
+    explanation.extend(_set_one_sided_diff("right", right, left, highlighter))
+    return explanation
+
+
+def _compare_gt_set(
+    left: AbstractSet[Any],
+    right: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+    verbose: int = 0,
+) -> list[str]:
+    explanation = _compare_gte_set(left, right, highlighter)
+    if not explanation:
+        return ["Both sets are equal"]
+    return explanation
+
+
+def _compare_lt_set(
+    left: AbstractSet[Any],
+    right: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+    verbose: int = 0,
+) -> list[str]:
+    explanation = _compare_lte_set(left, right, highlighter)
+    if not explanation:
+        return ["Both sets are equal"]
+    return explanation
+
+
+def _compare_gte_set(
+    left: AbstractSet[Any],
+    right: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+    verbose: int = 0,
+) -> list[str]:
+    return _set_one_sided_diff("right", right, left, highlighter)
+
+
+def _compare_lte_set(
+    left: AbstractSet[Any],
+    right: AbstractSet[Any],
+    highlighter: _HighlightFunc,
+    verbose: int = 0,
+) -> list[str]:
+    return _set_one_sided_diff("left", left, right, highlighter)

src/_pytest/assertion/_typing.py

@@ -0,0 +1,9 @@
+from __future__ import annotations
+
+from typing import Literal
+from typing import Protocol
+
+
+class _HighlightFunc(Protocol):  # noqa: PYI046
+    def __call__(self, source: str, lexer: Literal["diff", "python"] = "python") -> str:
+        """Apply highlighting to the given source."""

src/_pytest/assertion/util.py

@@ -8,19 +8,23 @@
 from collections.abc import Iterable
 from collections.abc import Mapping
 from collections.abc import Sequence
-from collections.abc import Set as AbstractSet
 import os
 import pprint
 from typing import Any
 from typing import Literal
-from typing import Protocol
 from unicodedata import normalize
 
 from _pytest import outcomes
 import _pytest._code
 from _pytest._io.pprint import PrettyPrinter
 from _pytest._io.saferepr import saferepr
 from _pytest._io.saferepr import saferepr_unlimited
+from _pytest.assertion._compare_set import _compare_eq_set
+from _pytest.assertion._compare_set import _compare_gt_set
+from _pytest.assertion._compare_set import _compare_gte_set
+from _pytest.assertion._compare_set import _compare_lt_set
+from _pytest.assertion._compare_set import _compare_lte_set
+from _pytest.assertion._typing import _HighlightFunc
 from _pytest.config import Config
 
 
@@ -38,11 +42,6 @@
 _config: Config | None = None
 
 
-class _HighlightFunc(Protocol):
-    def __call__(self, source: str, lexer: Literal["diff", "python"] = "python") -> str:
-        """Apply highlighting to the given source."""
-
-
 def dummy_highlighter(source: str, lexer: Literal["diff", "python"] = "python") -> str:
     """Dummy highlighter that returns the text unprocessed.
 
@@ -426,75 +425,6 @@ def _compare_eq_sequence(
     return explanation
 
 
-def _compare_eq_set(
-    left: AbstractSet[Any],
-    right: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-    verbose: int = 0,
-) -> list[str]:
-    explanation = []
-    explanation.extend(_set_one_sided_diff("left", left, right, highlighter))
-    explanation.extend(_set_one_sided_diff("right", right, left, highlighter))
-    return explanation
-
-
-def _compare_gt_set(
-    left: AbstractSet[Any],
-    right: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-    verbose: int = 0,
-) -> list[str]:
-    explanation = _compare_gte_set(left, right, highlighter)
-    if not explanation:
-        return ["Both sets are equal"]
-    return explanation
-
-
-def _compare_lt_set(
-    left: AbstractSet[Any],
-    right: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-    verbose: int = 0,
-) -> list[str]:
-    explanation = _compare_lte_set(left, right, highlighter)
-    if not explanation:
-        return ["Both sets are equal"]
-    return explanation
-
-
-def _compare_gte_set(
-    left: AbstractSet[Any],
-    right: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-    verbose: int = 0,
-) -> list[str]:
-    return _set_one_sided_diff("right", right, left, highlighter)
-
-
-def _compare_lte_set(
-    left: AbstractSet[Any],
-    right: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-    verbose: int = 0,
-) -> list[str]:
-    return _set_one_sided_diff("left", left, right, highlighter)
-
-
-def _set_one_sided_diff(
-    posn: str,
-    set1: AbstractSet[Any],
-    set2: AbstractSet[Any],
-    highlighter: _HighlightFunc,
-) -> list[str]:
-    explanation = []
-    diff = set1 - set2
-    if diff:
-        explanation.append(f"Extra items in the {posn} set:")
-        for item in diff:
-            explanation.append(highlighter(saferepr(item)))
-    return explanation
-
-
 def _compare_eq_dict(
     left: Mapping[Any, Any],
     right: Mapping[Any, Any],