Ruff rip

.github/scripts/type_completeness.py

@@ -2,21 +2,19 @@
 Builds a Markdown summary comparing pyright `--verifytypes` reports for a
 PR's base and head commits, for posting as a PR comment.
 """
+
 from __future__ import annotations
 
 import argparse
 import json
 from pathlib import Path
-from typing import (
-    Any,
-    Literal
-)
+from typing import Any, Literal
 
 # Decorates the patch coverage table.
 STATUS_ICON = {"known": "✅", "ambiguous": "⚠️", "unknown": "❌"}
 
 
-def status_of(symbol: dict[str, Any]) -> Literal['known', 'ambiguous', 'unknown']:
+def status_of(symbol: dict[str, Any]) -> Literal["known", "ambiguous", "unknown"]:
     """
     Maps the --verifytypes JSON boolean flags, isTypeKnown and isTypeAmbiguous, to internal
     representation in script: known, ambiguous, and unknown.
@@ -306,7 +304,8 @@ def build_summary(base_path: Path, head_path: Path, run_url: str | None = None)
         if removed_names:
             parts.append(f"{len(removed_names)} no longer exported")
         sections += [
-            "**Patch (exported symbols added or changed by this PR):** " + "; ".join(parts),
+            "**Patch (exported symbols added or changed by this PR):** "
+            + "; ".join(parts),
             "",
             render_counts_table([("Patch", patch_counts)]),
             "",

.github/workflows/ruff.yml

@@ -20,52 +20,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-        with:
-          fetch-depth: 0
-
-      - name: Determine changed Python/notebook files
-        id: changed
-        run: |
-          if [ "${{ github.event_name }}" = "pull_request" ]; then
-            base="origin/${{ github.event.pull_request.base.ref }}"
-          elif [ "${{ github.ref }}" = "refs/heads/main" ]; then
-            # origin/main already reflects this push after checkout, so diffing
-            # against it here would always be empty. Use the pre-push state instead.
-            base="${{ github.event.before }}"
-            # New branch or force-push: 'before' may not exist locally (or be all-zeros).
-            if ! git cat-file -e "$base" 2>/dev/null; then
-              base="HEAD^"
-              git cat-file -e "$base" 2>/dev/null || base=""
-            fi
-          else
-            base="origin/main"
-          fi
-
-          # Base ref not fetched/available for some reason: fall back to checking everything.
-          if [ -n "$base" ] && ! git cat-file -e "$base" 2>/dev/null; then
-            base=""
-          fi
-
-          if [ -z "$base" ]; then
-            files=$(git ls-files '*.py' '*.ipynb' | xargs)
-          else
-            files=$(git diff --name-only --diff-filter=ACMR "$base"...HEAD -- '*.py' '*.ipynb' | xargs)
-          fi
-
-          echo "files=$files" >> "$GITHUB_OUTPUT"
 
       - name: Install uv
-        if: steps.changed.outputs.files != ''
         uses: astral-sh/setup-uv@v7
         with:
           version: "latest"
 
       - name: Run ruff
-        if: steps.changed.outputs.files != ''
         run: |
-          uvx ruff@0.16.1 check --force-exclude --config lint.per-file-ignores={} --output-format=github ${{ steps.changed.outputs.files }}
+          uvx ruff@0.16.1 check --force-exclude --output-format=github .
 
       - name: Run ruff format
-        if: (success() || failure()) && steps.changed.outputs.files != ''
+        if: success() || failure()
         run: |
-          uvx ruff@0.16.1 format --check --diff --force-exclude ${{ steps.changed.outputs.files }}
+          uvx ruff@0.16.1 format --check --diff --force-exclude .

.pre-commit-config.yaml

@@ -6,14 +6,8 @@ repos:
       - id: ruff
         name: ruff
         entry: bash -c '
-          base=$(git rev-parse --verify --quiet origin/main || git rev-parse --verify --quiet main) &&
-          files=$(git diff --name-only --diff-filter=ACMR "$base"...HEAD -- "*.py" "*.ipynb") &&
-          if [ -z "$files" ]; then
-            echo "ruff - no changed files to check";
-          else
-            uv run ruff check --force-exclude --config lint.per-file-ignores={} $files &&
-            uv run ruff format --check --diff --force-exclude $files;
-          fi'
+          uv run ruff check --force-exclude . &&
+          uv run ruff format --check --diff --force-exclude .'
         language: system
         pass_filenames: false
         always_run: true

ARCHITECTURE.md

@@ -166,10 +166,12 @@ from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
     from chainladder.core.typing import TriangleProtocol
+
     _MixinBase = TriangleProtocol
 else:
     _MixinBase = object
 
+
 class TriangleMixin(_MixinBase):
     # Pyright sees TriangleProtocol as the base — self has .shape, .values, .sum, etc.
     # At runtime the base is object — no Protocol stubs in the MRO.
@@ -191,8 +193,8 @@ if TYPE_CHECKING:
     from chainladder import Triangle
     from chainladder.core.typing import TriangleProtocol
 
-def transform(X: TriangleProtocol) -> Triangle:
-    ...
+
+def transform(X: TriangleProtocol) -> Triangle: ...
 ```
 
 - **Input typed as `TriangleProtocol`**: accepts any object that structurally satisfies the protocol (a real `Triangle`, a mock in tests, a future subclass) without requiring a concrete import.

chainladder/adjustments/__init__.py

@@ -11,5 +11,5 @@
     "ParallelogramOLF",
     "Trend",
     "TrendConstant",
-    "DisposalRate"
+    "DisposalRate",
 ]

chainladder/adjustments/tests/test_trend.py

@@ -5,12 +5,14 @@
 def test_trend1(clrd):
     tri = clrd[["CumPaidLoss", "EarnedPremDIR"]].sum()
     lhs = (
-        cl.CapeCod(0.05)
+        cl
+        .CapeCod(0.05)
         .fit(tri["CumPaidLoss"], sample_weight=tri["EarnedPremDIR"].latest_diagonal)
         .ibnr_
     )
     rhs = (
-        cl.CapeCod()
+        cl
+        .CapeCod()
         .fit(
             cl.Trend(0.05).fit_transform(tri["CumPaidLoss"]),
             sample_weight=tri["EarnedPremDIR"].latest_diagonal,
@@ -24,7 +26,8 @@ def test_trend2(raa):
     tri = raa
     assert (
         abs(
-            cl.Trend(
+            cl
+            .Trend(
                 trends=[0.05, 0.05],
                 dates=[(None, "1985"), ("1985", None)],
                 axis="origin",

chainladder/core/io.py

@@ -1,6 +1,7 @@
 """
 Support Triangle I/O capabilities.
 """
+
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at https://mozilla.org/MPL/2.0/.
@@ -13,7 +14,7 @@
 
 class TriangleIO:
     def to_pickle(self, path, protocol=None):
-        """ Serializes triangle object to pickle.
+        """Serializes triangle object to pickle.
 
         Parameters
         ----------
@@ -53,7 +54,7 @@ def to_pickle(self, path, protocol=None):
             dill.dump(self, pkl)
 
     def to_json(self):
-        """ Serializes triangle object to json format
+        """Serializes triangle object to json format
 
         Returns
         -------
@@ -88,8 +89,13 @@ def to_json(self):
             "is_pattern": self.is_pattern,
             "columns": list(self.columns),
         }
-        out = self.cum_to_incr().dev_to_val().to_frame(
-            keepdims=True, origin_as_datetime=True).fillna(0)
+        out = (
+            self
+            .cum_to_incr()
+            .dev_to_val()
+            .to_frame(keepdims=True, origin_as_datetime=True)
+            .fillna(0)
+        )
         x = out.reset_index().to_json(orient="split", date_unit="ns")
         json_dict = {"metadata": json.dumps(metadata), "data": x}
         sub_tris = [k for k, v in vars(self).items() if isinstance(v, TriangleIO)]
@@ -99,17 +105,17 @@ def to_json(self):
         dfs = [k for k, v in vars(self).items() if isinstance(v, pd.DataFrame)]
         json_dict["dfs"] = {df: getattr(self, df).to_json() for df in dfs}
         dfs = [k for k, v in vars(self).items() if isinstance(v, pd.Series)]
-        json_dict["dfs"].update(
-            {df: getattr(self, df).to_frame().to_json() for df in dfs}
-        )
+        json_dict["dfs"].update({
+            df: getattr(self, df).to_frame().to_json() for df in dfs
+        })
         return json.dumps(json_dict)
 
 
 class EstimatorIO:
-    """ Class intended to allow persistence of estimator objects """
+    """Class intended to allow persistence of estimator objects"""
 
     def to_pickle(self, path, protocol=None):
-        """ Serializes triangle object to pickle.
+        """Serializes triangle object to pickle.
 
         Parameters
         ----------
@@ -149,7 +155,7 @@ def to_pickle(self, path, protocol=None):
             dill.dump(self, pkl)
 
     def to_json(self):
-        """ Serializes triangle object to json format
+        """Serializes triangle object to json format
 
         Returns
         -------

chainladder/core/slice.py

@@ -562,6 +562,16 @@ def __setitem__(
         -------
         None
         """
+        # Case full slice, e.g. tri[:] = value: mirror pandas' df[:] = value by
+        # broadcasting across every cell rather than treating ":" as a column label.
+        if isinstance(key, slice):
+            if key == slice(None, None, None):
+                self.iloc[:] = value
+                return
+            raise TypeError(
+                "Partial slicing is not supported for Triangle column assignment. "
+                "Use tri.iloc[...] or tri.loc[...] to set values by position or label."
+            )
         xp: ModuleType = self.get_array_module()
         # Case callable, create lazy-eval virtual columns, but do not compute.
         if callable(value):

chainladder/core/tests/test_correlation.py

@@ -3,18 +3,23 @@
 
 raa = cl.load_sample("RAA")
 
+
 def test_val_corr_total_true():
     assert raa.valuation_correlation(p_critical=0.5, total=True)
 
+
 def test_val_corr_total_false():
     assert raa.valuation_correlation(p_critical=0.5, total=False)
 
+
 def test_dev_corr():
     assert raa.development_correlation(p_critical=0.5)
 
+
 def test_dev_corr_sparse():
-    assert raa.set_backend('sparse').development_correlation(p_critical=0.5)
+    assert raa.set_backend("sparse").development_correlation(p_critical=0.5)
+
 
 def test_validate_critical():
     with pytest.raises(ValueError):
-        raa.valuation_correlation(p_critical=1.5, total=True)
+        raa.valuation_correlation(p_critical=1.5, total=True)

chainladder/core/tests/test_slicing.py

@@ -689,6 +689,48 @@ def test_setitem_existing_column_array_value(raa: Triangle) -> None:
     assert tri["values"] == raa["values"] * 3
 
 
+def test_setitem_full_slice_broadcasts_value(raa: Triangle) -> None:
+    """
+    Assigning through a bare full slice, e.g. tri[:] = 0, should broadcast the
+    value across every cell like pandas' df[:] = value, rather than being
+    misread as a column label.
+
+    Parameters
+    ----------
+    raa: Triangle
+        The raa sample data set fixture.
+
+    Returns
+    -------
+    None
+    """
+    tri = raa.copy()
+    if tri.array_backend == "sparse":
+        pytest.skip("Test is specific to the numpy backend.")
+    tri[:] = 0
+    assert list(tri.columns) == list(raa.columns)
+    assert np.nansum(tri.values) == 0
+
+
+def test_setitem_partial_slice_raises(raa: Triangle) -> None:
+    """
+    Assigning through a partial slice key is ambiguous for column assignment
+    and should raise rather than silently creating a bogus column.
+
+    Parameters
+    ----------
+    raa: Triangle
+        The raa sample data set fixture.
+
+    Returns
+    -------
+    None
+    """
+    tri = raa.copy()
+    with pytest.raises(TypeError):
+        tri[1:3] = 0
+
+
 def test_sparse_column_assignment(prism):
     t = prism.copy()
     out = t["Paid"]