adding part of a test

jdaviz/configs/specviz/plugins/unit_conversion/tests/test_unit_conversion.py

@@ -198,6 +198,11 @@ def test_sb_unit_conversion(cubeviz_helper):
     viewer_1d = cubeviz_helper.app.get_viewer(
         cubeviz_helper._default_spectrum_viewer_reference_name)
 
+    assert label_mouseover.as_text() == (
+            "Pixel x=00010.0 y=00008.0 Value +1.00000e+06 MJy / sr",
+            "World 13h39m59.7037s +27d00m03.2400s (ICRS)",
+            "204.9987654313 27.0008999946 (deg)")
+
     uc_plg.flux_or_sb.selected = 'Surface Brightness'
 
     # Surface Brightness conversion
@@ -251,3 +256,51 @@ def test_sb_unit_conversion(cubeviz_helper):
 
     la = cubeviz_helper.plugins['Line Analysis']._obj
     assert la.dataset.get_selected_spectrum(use_display_units=True)
+
+def test_mouseover_display_unit(cubeviz_helper):
+
+        # custom cube to have Surface Brightness units
+    wcs_dict = {"CTYPE1": "WAVE-LOG", "CTYPE2": "DEC--TAN", "CTYPE3": "RA---TAN",
+                "CRVAL1": 4.622e-7, "CRVAL2": 27, "CRVAL3": 205,
+                "CDELT1": 8e-11, "CDELT2": 0.0001, "CDELT3": -0.0001,
+                "CRPIX1": 0, "CRPIX2": 0, "CRPIX3": 0, "PIXAR_SR": 8e-11}
+    w = WCS(wcs_dict)
+    flux = np.zeros((30, 20, 3001), dtype=np.float32)
+    flux[5:15, 1:11, :] = 1
+    cube = Spectrum1D(flux=flux * (u.MJy / u.sr), wcs=w, meta=wcs_dict)
+    cubeviz_helper.load_data(cube, data_label="test")
+
+    uc_plg = cubeviz_helper.plugins['Unit Conversion']
+    uc_plg.open_in_tray()
+
+    # ensure that per solid angle cube defaults to Flux spectrum
+    assert uc_plg.flux_or_sb == 'Flux'
+
+    # make sure the mouseover display unit for a cube loaded in surface
+    # brighntess units reflects the selected 'flux' unit
+
+
+    # test mouseover while spectral y axis is in 'Flux'
+    # coords_info should pick up the selected flux unit to display the
+    # data unit, which is in surface brightness
+    label_mouseover._viewer_mouse_event(
+        flux_viewer, {"event": "mousemove", "domain": {"x": 10, "y": 8}}
+    )
+
+    assert label_mouseover.as_text() == (
+            "Pixel x=00010.0 y=00008.0 Value +1.00000e+00 MJy / sr",
+            "World 13h39m59.7037s +27d00m03.2400s (ICRS)",
+            "204.9987654313 27.0008999946 (deg)")
+
+    # change unit, but spectral y axis is still in 'flux'
+    # make sure surface brightness display unit still updates
+    # accordingly 
+    uc_plg.flux_unit = 'Jy'
+
+    assert label_mouseover.as_text() == (
+            "Pixel x=00010.0 y=00008.0 Value +1.00000e+06 Jy / sr",
+            "World 13h39m59.7037s +27d00m03.2400s (ICRS)",
+            "204.9987654313 27.0008999946 (deg)")
+
+
+