TST: test against minimal env

.github/workflows/test.yml

@@ -20,6 +20,9 @@ jobs:
         - '3.10'
         - '3.11'
         - '3.12'
+        include:
+        - os: ubuntu-20.04
+          python-version: '3.9'
       fail-fast: false
 
     steps:
@@ -28,15 +31,26 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
+    - if: ${{ matrix.os == 'ubuntu-20.04' }}
+      name: Install minimal env
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install tomli tomli_w
+        python scripts/pin_requirements.py
+        python -m pip uninstall --yes tomli tomli_w
+        python -m pip install -e . --only-binary ':all:'
+        python -m pip install pytest pytest-mpl pytest-cov
+    - if: ${{ matrix.os != 'ubuntu-20.04' }}
+      name: Install full test env
       run: |
         python -m pip install --upgrade pip setuptools wheel
         pip install -r requirements_dev.txt
     - name: Test deployment
       run: |
-        check-manifest
+        pipx run check-manifest
         pipx run build --sdist
-        twine check dist/*
+        pipx run twine check dist/*
+    - run: python -m pip freeze
     - name: Test package
       run: |
         pytest --color=yes

MANIFEST.in

@@ -8,7 +8,7 @@ recursive-include cmasher data/*
 recursive-exclude cmasher/colormaps *
 recursive-include cmasher/colormaps cm_*
 
-exclude docs joss_paper .git*
+exclude docs joss_paper .git* scripts/*
 recursive-exclude docs *
 recursive-exclude joss_paper *
 recursive-exclude .github *

cmasher/tests/test_utils.py

@@ -1,11 +1,10 @@
 # %% IMPORTS
 # Built-in imports
 import os
-from importlib.util import module_from_spec, spec_from_file_location
+from importlib.util import find_spec, module_from_spec, spec_from_file_location
 from os import path
 
 # Package imports
-import cmocean as cmo
 import matplotlib as mpl
 import matplotlib.pyplot as plt
 import numpy as np
@@ -28,6 +27,26 @@
     view_cmap,
 )
 
+HAS_VISCM = find_spec("viscm") is not None
+
+
+def _MPL38_colormap_eq(cmap, other) -> bool:
+    # equality check for two colormaps
+    # this is adapted from Colormap.__eq__ (mpl 3.8)
+    # in previous versions, colormaps compared as != unless they
+    # 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:
+        return False
+    # To compare lookup tables the Colormaps have to be initialized
+    if not cmap._isinit:
+        cmap._init()
+    if not other._isinit:
+        other._init()
+    return np.array_equal(cmap._lut, other._lut)
+
+
 # Save the path to this directory
 dirpath = path.dirname(__file__)
 
@@ -70,7 +89,11 @@ def test_standalone_rainforest(self):
         # identity equality isn't achievable since mpl.colormaps.__getitem__
         # may return a copy
         assert cmap_new == mod.cmap
-        assert cmap_old == cmap_new
+
+        if mpl.__version_info__ >= (3, 8):
+            assert cmap_old == cmap_new
+        else:
+            assert _MPL38_colormap_eq(cmap_old, cmap_new)
 
         # Check if the values in both colormaps are the same
         assert np.allclose(cmap_old.colors, cmap_new.colors)
@@ -90,7 +113,11 @@ def test_standalone_infinity(self):
 
         # Check if the colormap in MPL has been updated
         cmap_new = mpl.colormaps["cmr.infinity"]
-        assert cmap_new == mod.cmap
+        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
@@ -247,6 +274,7 @@ def test_cmap_file_HEX(self):
         import_cmaps(path.join(dirpath, "data/cm_hex.txt"))
 
     # Test if providing a cmap .jscm-file works
+    @pytest.mark.skipif(not HAS_VISCM, reason="viscm is required")
     def test_cmap_file_jscm(self):
         cmap_path = path.join(dirpath, "data/cm_rainforest_jscm.jscm")
         import_cmaps(cmap_path)

pyproject.toml

@@ -68,6 +68,7 @@ addopts = "--mpl -v --cov --cov-config=pyproject.toml --cov-report=term-missing"
 filterwarnings = [
   "error",
   "ignore:FigureCanvasAgg is non-interactive:UserWarning",
+  "ignore:Matplotlib is currently using agg, which is a non-GUI backend:UserWarning",
   # this future warning is internal to viscm
   "ignore: Deprecated. CatmulClark builds nicer splines.:FutureWarning",
   # internal to colorspacious

requirements_dev.txt

@@ -1,6 +1,4 @@
 -e .
-check-manifest
-cmocean>=2.0
 pyqt5>=5.12
 pytest>=4.6.0
 pytest-cov
@@ -9,6 +7,5 @@ pytest-mpl
 readme_renderer[md]
 scipy>=1.0.0
 setuptools>=38.6.0
-twine>=1.13.0
 viscm>=0.10
 wheel>=0.31.0

scripts/pin_requirements.py

@@ -0,0 +1,19 @@
+import sys
+
+import tomli_w
+
+if sys.version_info >= (3, 11):
+    import tomllib
+else:
+    import tomli as tomllib
+
+
+with open("pyproject.toml", "rb") as fr:
+    conf = tomllib.load(fr)
+
+conf["project"]["dependencies"] = [
+    req.replace(">=", "==") for req in conf["project"]["dependencies"]
+]
+
+with open("pyproject.toml", "wb") as fw:
+    tomli_w.dump(conf, fw)