TST: reintroduce coverage measurement and improve coverage to 100% (e…

…xcluding defensive programming lines)

.github/workflows/test.yml

@@ -72,9 +72,49 @@ jobs:
       shell: bash # for windows-compat
       run: |
         source .venv/${{matrix.venv-loc}}/activate
-        coverage run -m pytest --color=yes --mpl
+        coverage run --parallel-mode -m pytest --color=yes --mpl
 
-        # TODO: add coverage report + upload step (use parallel mode)
+    - name: Upload coverage data
+      # only using reports from ubuntu because
+      # combining reports from multiple platforms is tricky (or impossible ?)
+      if: startsWith( matrix.os, 'ubuntu' )
+      uses: actions/upload-artifact@b4b15b8c7c6ac21ea08fcf65892d2ee8f75cf882 # v4.4.3
+      with:
+        name: cmasher_coverage_data-${{ matrix.os }}-${{ matrix.python-version }}
+        path: .coverage.*
+        if-no-files-found: ignore
+        include-hidden-files: true
+
+
+  coverage:
+    name: Combine & check coverage
+    runs-on: ubuntu-latest
+    needs: build
+
+    steps:
+    - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+    - uses: astral-sh/setup-uv@3b9817b1bf26186f03ab8277bab9b827ea5cc254 # v3.2.0
+    - run: | # uv sync --only-group covcheck
+        uv venv
+        uv pip install . -r requirements/dev.txt
+
+    - uses: actions/download-artifact@fa0a91b85d4f404e444e00e005971372dc801d16 # v4.1.8
+      with:
+        pattern: cmasher_coverage_data-*
+        merge-multiple: true
+
+    - name: Check coverage
+      run: |
+        uv run coverage combine
+        uv run coverage html --skip-covered --skip-empty
+        uv run coverage report --fail-under=100
+
+    - name: Upload HTML report if check failed.
+      uses: actions/upload-artifact@b4b15b8c7c6ac21ea08fcf65892d2ee8f75cf882 # v4.4.3
+      with:
+        name: cmasher_coverage_report
+        path: htmlcov
+      if: ${{ failure() }}
 
   type-check:
     name: type check w/ Python ${{ matrix.python-version }}

conftest.py

@@ -28,7 +28,7 @@ def pytest_sessionstart(session):
 
 def pytest_sessionfinish(session, exitstatus):
     AT_END = set(mpl.colormaps.keys())
-    if diff := (AT_END - AT_START):
+    if diff := (AT_END - AT_START):  # pragma: no cover
         print(
             f"The following colormaps appear to have leaked during test session {diff}",
             file=sys.stderr,

pyproject.toml

@@ -64,11 +64,29 @@ filterwarnings = [
   'ignore:datetime\.datetime\.utcfromtimestamp\(\) is deprecated:DeprecationWarning',
 ]
 
+[tool.coverage.report]
+show_missing = true
+skip_covered = true
+exclude_lines = [
+    # a more strict default pragma
+    "\\# pragma: no cover\\b",
+
+    # allow defensive code
+    "^\\s*raise NotImplementedError\\b",
+
+    # typing-related code
+    "^if TYPE_CHECKING:",
+    ": \\.\\.\\.(\\s*#.*)?$",
+    "^ +\\.\\.\\.$",
+    "-> ['\"]?NoReturn['\"]?:",
+]
+
 [tool.coverage.run]
-include = ["cmasher/*"]
 omit = [
-    "cmasher/__version__*",
-    "cmasher/app_usage.py",
+  "scripts/*",
+  "src/cmasher/__version__*",
+  "src/cmasher/app_usage.py",
+  "*_test_copy.py",
 ]
 
 [tool.ruff.lint]

src/cmasher/tests/test_utils.py

@@ -1,8 +1,10 @@
 # %% IMPORTS
 # Built-in imports
 import os
+import shutil
 from importlib.util import find_spec, module_from_spec, spec_from_file_location
 from os import path
+from pathlib import Path
 
 # Package imports
 import matplotlib as mpl
@@ -38,12 +40,14 @@ def _MPL38_colormap_eq(cmap, other) -> bool:
     # had the exact same name, which is not what we care about here
     from matplotlib.colors import Colormap
 
-    if not isinstance(other, Colormap) or cmap.colorbar_extend != other.colorbar_extend:
+    if (
+        not isinstance(other, Colormap) or cmap.colorbar_extend != other.colorbar_extend
+    ):  # pragma: no cover
         return False
     # To compare lookup tables the Colormaps have to be initialized
     if not cmap._isinit:
         cmap._init()
-    if not other._isinit:  # type: ignore [attr-defined]
+    if not other._isinit:  # type: ignore [attr-defined] # pragma: no cover
         other._init()  # type: ignore [attr-defined]
     return np.array_equal(cmap._lut, other._lut)  # type: ignore [attr-defined]
 
@@ -63,6 +67,7 @@ def _MPL38_colormap_eq(cmap, other) -> bool:
 
 # Obtain list of all colormaps registered in MPL
 mpl_cmaps = plt.colormaps()
+mpl_cmaps_as_str: list[str] = list(mpl_cmaps)
 
 
 # %% PYTEST CLASSES AND FUNCTIONS
@@ -186,21 +191,26 @@ def test_invalid_nodes(self, cmaps, nodes):
 
 # Pytest class for create_cmap_mod
 class Test_create_cmap_mod:
-    # Test if a standalone module of rainforest can be created
-    def test_standalone_rainforest(self):
+    # Test if a standalone module can be created
+    @pytest.mark.parametrize("name", ["rainforest", "infinity"])
+    def test_standalone_copy(self, name, tmp_path):
         # Obtain the currently registered version of rainforest
-        cmap_old = mpl.colormaps["cmr.rainforest"]
+        cmap_old = mpl.colormaps[f"cmr.{name}"]
 
         # Create standalone module for rainforest
-        cmap_path = create_cmap_mod("rainforest", _copy_name="rainforest_copy")
+        cmap_path = create_cmap_mod(
+            name,
+            save_dir=tmp_path,
+            _copy_name=f"{name}_test_copy",
+        )
 
         # Try to import this module
-        spec = spec_from_file_location("rainforest_copy", cmap_path)
+        spec = spec_from_file_location(f"{name}_test_copy", cmap_path)
         mod = module_from_spec(spec)
         spec.loader.exec_module(mod)
 
         # Check if the colormap in MPL has been updated
-        cmap_new = mpl.colormaps["cmr.rainforest_copy"]
+        cmap_new = mpl.colormaps[f"cmr.{name}_test_copy"]
 
         # identity equality isn't achievable since mpl.colormaps.__getitem__
         # may return a copy
@@ -214,39 +224,18 @@ def test_standalone_rainforest(self):
         # Check if the values in both colormaps are the same
         assert np.allclose(cmap_old.colors, cmap_new.colors)
 
-    # Test if a standalone module of infinity can be created
-    def test_standalone_infinity(self):
-        # Obtain the currently registered version of infinity
-        cmap_old = mpl.colormaps["cmr.infinity"]
-
-        # Create standalone module for infinity
-        cmap_path = create_cmap_mod("infinity", _copy_name="inifinity_copy")
-
-        # Try to import this module
-        spec = spec_from_file_location("infinity_copy", cmap_path)
-        mod = module_from_spec(spec)
-        spec.loader.exec_module(mod)
-
-        # Check if the colormap in MPL has been updated
-        cmap_new = mpl.colormaps["cmr.infinity"]
-        if mpl.__version_info__ >= (3, 8):
-            assert cmap_old == cmap_new
-        else:
-            assert _MPL38_colormap_eq(cmap_old, cmap_new)
-
-        assert cmap_old == cmap_new
-
-        # Check if the values in both colormaps are the same
-        assert np.allclose(cmap_old.colors, cmap_new.colors)
-
-        # Check that the shifted version of infinity also exists
-        assert "cmr.infinity_s" in plt.colormaps()
+        if name == "infinity":
+            # Check that the shifted version of infinity also exists
+            assert "cmr.infinity_s" in plt.colormaps()
 
     # Test if providing an invalid colormap name fails
-    def test_invalid_cmap(self):
+    def test_invalid_cmap(self, tmp_path):
         # Check if a ValueError is raised
         with pytest.raises(ValueError):
-            create_cmap_mod("this is an incorrect colormap name")
+            create_cmap_mod(
+                "this is an incorrect colormap name",
+                save_dir=tmp_path,
+            )
 
 
 # Pytest class for create_cmap_overview
@@ -267,13 +256,16 @@ def test_list_cat(self):
         create_cmap_overview(["cmr.rainforest"])
 
     # Test if providing all MPL colormap objects works
-    def test_mpl_cmaps_objs(self):
+    @pytest.mark.parametrize("sort", ["perceptual", "lightness"])
+    def test_mpl_cmaps_objs(self, sort):
         cmaps = map(mpl.colormaps.__getitem__, mpl_cmaps)
-        create_cmap_overview(cmaps, sort="perceptual")
+        create_cmap_overview(cmaps, sort=sort)
 
     # Test if providing all MPL colormap names works
-    def test_mpl_cmaps_names(self):
-        create_cmap_overview(mpl_cmaps, sort="lightness")
+    @pytest.mark.parametrize("cmaps", [mpl_cmaps, mpl_cmaps_as_str])
+    @pytest.mark.parametrize("sort", ["perceptual", "lightness"])
+    def test_mpl_cmaps_names(self, cmaps, sort):
+        create_cmap_overview(cmaps, sort=sort)
 
     # Test if the lightness profiles can be plotted
     def test_lightness_profiles(self):
@@ -381,6 +373,18 @@ def test_cmap_file_npy(self):
             _skip_registration=True,
         )
 
+    def test_resilience(self, tmp_path):
+        # check that, in the presence of a npy and a txt,
+        # import_cmaps ignores the second
+        src = Path(dirpath).parent.joinpath("colormaps", "cm_rainforest.npy")
+        shutil.copy(src, tmp_path / "cm_rainforest.npy")
+        shutil.copy(src, tmp_path / "cm_rainforest.txt")
+
+        import_cmaps(
+            tmp_path,
+            _skip_registration=True,
+        )
+
     # Test if providing a cmap .txt-file with 8-bit values works
     def test_cmap_file_8bit(self):
         import_cmaps(path.join(dirpath, "data/cm_8bit.txt"))

src/cmasher/utils.py

@@ -7,7 +7,7 @@
 
 # %% IMPORTS
 # Built-in imports
-import sys
+import os
 from collections import OrderedDict
 from collections.abc import Callable
 from glob import glob
@@ -72,14 +72,16 @@
 
 # %% HELPER FUNCTIONS
 # Define function for obtaining the sorting order for lightness ranking
-def _get_cmap_lightness_rank(cmap: CMAP) -> tuple[int, int, float, float, float, str]:
+def _get_cmap_lightness_rank(
+    cmap: Colormap,
+) -> tuple[int, int, float, float, float, str]:
     """
     Returns a tuple of objects used for sorting the provided `cmap` based
     on its lightness profile.
 
     Parameters
     ----------
-    cmap : str or :obj:`~matplotlib.colors.Colormap` object
+    cmap : :obj:`~matplotlib.colors.Colormap` object
         The registered name of the colormap in :mod:`matplotlib.cm` or its
         corresponding :obj:`~matplotlib.colors.Colormap` object.
 
@@ -105,9 +107,6 @@ def _get_cmap_lightness_rank(cmap: CMAP) -> tuple[int, int, float, float, float,
 
     """
     # Obtain the colormap
-    if isinstance(cmap, str):
-        cmap = mpl.colormaps[cmap]
-
     cm_type = get_cmap_type(cmap)
 
     # Determine lightness profile stats for sequential/diverging/cyclic
@@ -177,7 +176,7 @@ def _get_cmap_lightness_rank(cmap: CMAP) -> tuple[int, int, float, float, float,
 
 # Define function for obtaining the sorting order for perceptual ranking
 def _get_cmap_perceptual_rank(
-    cmap: CMAP,
+    cmap: Colormap,
 ) -> tuple[int, int, float, float, float, float, str]:
     """
     In addition to returning the lightness rank as given by
@@ -187,7 +186,7 @@ def _get_cmap_perceptual_rank(
 
     Parameters
     ----------
-    cmap : str or :obj:`~matplotlib.colors.Colormap` object
+    cmap : :obj:`~matplotlib.colors.Colormap` object
         The registered name of the colormap in :mod:`matplotlib.cm` or its
         corresponding :obj:`~matplotlib.colors.Colormap` object.
 
@@ -205,9 +204,6 @@ def _get_cmap_perceptual_rank(
 
     """
     # Obtain the colormap
-    if isinstance(cmap, str):
-        cmap = mpl.colormaps[cmap]
-
     cm_type = get_cmap_type(cmap)
 
     # Determine perceptual range for sequential/diverging/cyclic
@@ -342,7 +338,10 @@ def combine_cmaps(
 
 # This function creates a standalone module of a CMasher colormap
 def create_cmap_mod(
-    cmap: str, *, save_dir: str = ".", _copy_name: str | None = None
+    cmap: str,
+    *,
+    save_dir: str | os.PathLike[str] = ".",
+    _copy_name: str | None = None,
 ) -> str:
     """
     Creates a standalone Python module of the provided *CMasher* `cmap` and
@@ -361,7 +360,7 @@ def create_cmap_mod(
 
     Optional
     --------
-    save_dir : str. Default: '.'
+    save_dir: os.PathLike Default: '.'
         The path to the directory where the module must be saved.
         By default, the current directory is used.
 
@@ -911,7 +910,7 @@ def sort_key(x):
                     fontsize=10,
                     c=text_color,
                 )
-        else:
+        else:  # pragma: no cover
             raise RuntimeError
 
     # If savefig is not None, save the figure
@@ -1055,7 +1054,7 @@ def get_cmap_type(cmap: CMAP) -> str:
 
     # MISC 1
     # If the colormap has only a single lightness, it is misc
-    elif np.allclose(diff_L, 0):
+    elif np.allclose(diff_L, 0):  # pragma: no cover
         return "misc"
 
     # SEQUENTIAL
@@ -1622,16 +1621,14 @@ def view_cmap(
 
     # If show_grayscale is True, show both plots instead of just one
     if show_grayscale:
-        if isinstance(ax, Axes):
-            # defensive programming
+        if isinstance(ax, Axes):  # pragma: no cover
             raise RuntimeError
         ax[0].imshow(data, cmap=cmap, aspect="auto")
         ax[0].set_axis_off()
         ax[1].imshow(data, cmap=cmap_L, aspect="auto")
         ax[1].set_axis_off()
     else:
-        if not isinstance(ax, Axes):
-            # defensive programming
+        if not isinstance(ax, Axes):  # pragma: no cover
             raise RuntimeError
         ax.imshow(data, cmap=cmap, aspect="auto")
         ax.set_axis_off()