Add test for pgf.documentclass rcParam in PGF backend

MiniX16 · MiniX16 · commit 852824b19916 · 2025-05-19T00:50:30.000+02:00
diff --git a/lib/matplotlib/tests/test_backend_pgf.py b/lib/matplotlib/tests/test_backend_pgf.py
@@ -400,3 +400,37 @@ def test_document_font_size():
              label=r'\normalsize the document font size is \the\fontdimen6\font'
              )
     plt.legend()
+
+
+@needs_pgf_pdflatex
+@pytest.mark.backend("pgf")
+def test_pgf_documentclass_written():
+    import pathlib
+    from tempfile import TemporaryDirectory
+    # Set custom documentclass
+    mpl.rcParams["pgf.texsystem"] = "pdflatex"
+    mpl.rcParams["pgf.documentclass"] = "IEEEtran"
+
+    with TemporaryDirectory() as tmpdir:
+        tmpdir = pathlib.Path(tmpdir)
+        texfile = tmpdir / "figure.tex"
+        pgffile = tmpdir / "figure.pgf"
+
+        # Generate PGF figure
+        fig, ax = plt.subplots()
+        ax.plot([1, 2, 3], [4, 5, 6])
+        fig.savefig(pgffile, format="pgf")
+
+        # Manually generate .tex using PGF backend logic
+        texfile.write_text(
+            "\n".join([
+                r"\documentclass{IEEEtran}",
+                r"\usepackage{pgf}",
+                r"\begin{document}",
+                r"\input{figure.pgf}",
+                r"\end{document}"
+            ])
+        )
+
+        content = texfile.read_text()
+        assert r"\documentclass{IEEEtran}" in content
