Create private method for importing spectral region objects (#2941)

* Create private method for importing spectral region objects

* Address review comments

* Add tests for list of modes and single SpectralRegion

* Fix style

jdaviz/configs/default/plugins/subset_plugin/subset_plugin.py

@@ -6,7 +6,7 @@
 import astropy.units as u
 from glue.core.message import EditSubsetMessage, SubsetUpdateMessage
 from glue.core.edit_subset_mode import (AndMode, AndNotMode, OrMode,
-                                        ReplaceMode, XorMode)
+                                        ReplaceMode, XorMode, NewMode)
 from glue.core.roi import CircularROI, CircularAnnulusROI, EllipticalROI, RectangularROI
 from glue.core.subset import RoiSubsetState, RangeSubsetState, CompositeSubsetState
 from glue.icons import icon_path
@@ -655,3 +655,33 @@ def _set_value_in_subset_definition(self, index, name, desired_key, new_value):
             if self.subset_definitions[index][i]['name'] == name:
                 self.subset_definitions[index][i]['value'] = new_value
                 break
+
+    def _import_spectral_regions(self, spec_region, mode=NewMode, viewer=None):
+        """
+        Method for importing a SpectralRegion object or list of SpectralRegion objects.
+
+        Parameters
+        ----------
+        spec_region : ~`specutils.SpectralRegion` object or list
+            The object that contains bounds for the spectral region or regions
+        mode : AndMode, AndNotMode, OrMode, ReplaceMode, XorMode, NewMode, or list
+            By default this is set to NewMode which creates a new subset per subregion.
+            OrMode will create a composite subset with each subregion corresponding
+            to a subregion of a single subset.
+        """
+        viewer_name = viewer or self.app._jdaviz_helper._default_spectrum_viewer_reference_name
+        range_viewer = self.app.get_viewer(viewer_name)
+        for index, sub_region in enumerate(spec_region):
+            if isinstance(mode, list):
+                if len(mode) != (len(spec_region) - 1):
+                    raise ValueError("list of mode must be size of spec_region minus one")
+                if index == 0:
+                    m = NewMode
+                else:
+                    m = mode[index - 1]
+            else:
+                m = mode
+            self.app.session.edit_subset_mode.mode = m
+            s = RangeSubsetState(lo=sub_region.lower.value, hi=sub_region.upper.value,
+                                 att=range_viewer.slice_component_label)
+            range_viewer.apply_subset_state(s)

jdaviz/configs/default/plugins/subset_plugin/tests/test_subset_plugin.py

@@ -3,7 +3,10 @@
 
 import numpy as np
 from astropy.nddata import NDData
+import astropy.units as u
+from specutils import SpectralRegion
 from glue.core.roi import EllipticalROI, CircularROI, CircularAnnulusROI, RectangularROI, XRangeROI
+from glue.core.edit_subset_mode import OrMode, NewMode, AndNotMode
 from numpy.testing import assert_allclose
 
 from jdaviz.configs.default.plugins.subset_plugin import utils
@@ -168,3 +171,29 @@ def test_circle_recenter_linking(roi_class, subset_info, imviz_helper, image_2d_
     for i, attr in enumerate(subset_info):
         assert subset_defs[0][i+1]['name'] == subset_info[attr]['wcs_name']
         assert_allclose(subset_defs[0][i+1]['value'], true_values_final[i]['value'])
+
+
+@pytest.mark.parametrize(
+    ('spec_regions', 'mode', 'len_subsets', 'len_subregions'),
+    [([SpectralRegion(5.772486091213352 * u.um, 6.052963676101135 * u.um),
+       SpectralRegion(6.494371022809778 * u.um, 6.724270682553864 * u.um),
+       SpectralRegion(7.004748267441649 * u.um, 7.3404016303483965 * u.um)], NewMode, 3, 1),
+     ((SpectralRegion(5.772486091213352 * u.um, 6.052963676101135 * u.um) +
+       SpectralRegion(6.494371022809778 * u.um, 6.724270682553864 * u.um) +
+       SpectralRegion(7.004748267441649 * u.um, 7.3404016303483965 * u.um)), OrMode, 1, 3),
+     ((SpectralRegion(5.772486091213352 * u.um, 6.052963676101135 * u.um) +
+       SpectralRegion(5.8 * u.um, 5.9 * u.um) +
+       SpectralRegion(6.494371022809778 * u.um, 6.724270682553864 * u.um) +
+       SpectralRegion(7 * u.um, 7.2 * u.um)), [AndNotMode, OrMode, OrMode], 1, 4),
+     (SpectralRegion(5.8 * u.um, 5.9 * u.um), None, 1, 1)
+     ]
+)
+def test_import_spectral_region(cubeviz_helper, spectrum1d_cube, spec_regions, mode, len_subsets,
+                                len_subregions):
+    cubeviz_helper.load_data(spectrum1d_cube)
+    cubeviz_helper.app.get_tray_item_from_name('g-subset-plugin')
+    plg = cubeviz_helper.plugins['Subset Tools']._obj
+    plg._import_spectral_regions(spec_region=spec_regions, mode=mode)
+    subsets = cubeviz_helper.app.get_subsets()
+    assert len(subsets) == len_subsets
+    assert len(subsets['Subset 1']) == len_subregions