Figure.savefig: Add a new test for the show parameter and simplify existing tests. (#3568)

* Get rid of try-except in test_figure_savefig_geotiff
* Simplify test_figure_savefig_unknown_extension
* Simplify test_figure_savefig with unittest.mock
* Add one more test for Figure.savefig(show=True)

Author: seisman

pygmt/tests/test_figure.py

@@ -17,6 +17,7 @@
 from pygmt.helpers import GMTTempFile
 
 _HAS_IPYTHON = bool(importlib.util.find_spec("IPython"))
+_HAS_RIOXARRAY = bool(importlib.util.find_spec("rioxarray"))
 
 
 def test_figure_region():
@@ -100,7 +101,7 @@ def test_figure_savefig_geotiff():
     geofname = Path("test_figure_savefig_geotiff.tiff")
     fig.savefig(geofname)
     assert geofname.exists()
-    # The .pgw should not exist
+    # The .pgw file should not exist
     assert not geofname.with_suffix(".pgw").exists()
 
     # Save as TIFF
@@ -109,7 +110,7 @@ def test_figure_savefig_geotiff():
     assert fname.exists()
 
     # Check if a TIFF is georeferenced or not
-    try:
+    if _HAS_RIOXARRAY:
         import rioxarray
         from rasterio.errors import NotGeoreferencedWarning
         from rasterio.transform import Affine
@@ -147,8 +148,6 @@ def test_figure_savefig_geotiff():
                     a=1.0, b=0.0, c=0.0, d=0.0, e=1.0, f=0.0
                 )
             assert len(record) == 1
-    except ImportError:
-        pass
     geofname.unlink()
     fname.unlink()
 
@@ -170,9 +169,7 @@ def test_figure_savefig_unknown_extension():
     """
     fig = Figure()
     fig.basemap(region="10/70/-300/800", projection="X3i/5i", frame="af")
-    prefix = "test_figure_savefig_unknown_extension"
-    fmt = "test"
-    fname = f"{prefix}.{fmt}"
+    fname = "test_figure_savefig_unknown_extension.test"
     with pytest.raises(GMTInvalidInput, match="Unknown extension '.test'."):
         fig.savefig(fname)
 
@@ -223,69 +220,23 @@ def test_figure_savefig():
     """
     Check if the arguments being passed to psconvert are correct.
     """
-    kwargs_saved = []
-
-    def mock_psconvert(*args, **kwargs):  # noqa: ARG001
-        """
-        Just record the arguments.
-        """
-        kwargs_saved.append(kwargs)
-
-    fig = Figure()
-    fig.psconvert = mock_psconvert
-
     prefix = "test_figure_savefig"
-
-    fname = f"{prefix}.png"
-    fig.savefig(fname)
-    assert kwargs_saved[-1] == {
-        "prefix": prefix,
-        "fmt": "g",
-        "crop": True,
-        "Qt": 2,
-        "Qg": 2,
-    }
-
-    fname = f"{prefix}.pdf"
-    fig.savefig(fname)
-    assert kwargs_saved[-1] == {
-        "prefix": prefix,
-        "fmt": "f",
-        "crop": True,
-        "Qt": 2,
-        "Qg": 2,
+    common_kwargs = {"prefix": prefix, "crop": True, "Qt": 2, "Qg": 2}
+    expected_kwargs = {
+        "png": {"fmt": "g", **common_kwargs},
+        "pdf": {"fmt": "f", **common_kwargs},
+        "eps": {"fmt": "e", **common_kwargs},
+        "kml": {"fmt": "g", "W": "+k", **common_kwargs},
     }
 
-    fname = f"{prefix}.png"
-    fig.savefig(fname, transparent=True)
-    assert kwargs_saved[-1] == {
-        "prefix": prefix,
-        "fmt": "G",
-        "crop": True,
-        "Qt": 2,
-        "Qg": 2,
-    }
-
-    fname = f"{prefix}.eps"
-    fig.savefig(fname)
-    assert kwargs_saved[-1] == {
-        "prefix": prefix,
-        "fmt": "e",
-        "crop": True,
-        "Qt": 2,
-        "Qg": 2,
-    }
+    with patch.object(Figure, "psconvert") as mock_psconvert:
+        fig = Figure()
+        for fmt, expected in expected_kwargs.items():
+            fig.savefig(f"{prefix}.{fmt}")
+            mock_psconvert.assert_called_with(**expected)
 
-    fname = f"{prefix}.kml"
-    fig.savefig(fname)
-    assert kwargs_saved[-1] == {
-        "prefix": prefix,
-        "fmt": "g",
-        "crop": True,
-        "Qt": 2,
-        "Qg": 2,
-        "W": "+k",
-    }
+        fig.savefig(f"{prefix}.png", transparent=True)
+        mock_psconvert.assert_called_with(fmt="G", **common_kwargs)
 
 
 def test_figure_savefig_worldfile():
@@ -309,6 +260,19 @@ def test_figure_savefig_worldfile():
                 fig.savefig(fname=imgfile.name, worldfile=True)
 
 
+def test_figure_savefig_show():
+    """
+    Check if the external viewer is launched when the show parameter is specified.
+    """
+    fig = Figure()
+    fig.basemap(region=[0, 1, 0, 1], projection="X1c/1c", frame=True)
+    prefix = "test_figure_savefig_show"
+    with patch("pygmt.figure.launch_external_viewer") as mock_viewer:
+        with GMTTempFile(prefix=prefix, suffix=".png") as imgfile:
+            fig.savefig(imgfile.name, show=True)
+        assert mock_viewer.call_count == 1
+
+
 @pytest.mark.skipif(not _HAS_IPYTHON, reason="run when IPython is installed")
 def test_figure_show():
     """