fix(empty transient arrays): #2145

Empty transient array block were not being read or written correctly.

Author: scottrp

autotest/regression/test_mf6.py

@@ -2062,7 +2062,7 @@ def test004_create_tests_bcfss(function_tmpdir, example_data_path):
         readasarrays=True,
         save_flows=True,
         auxiliary=[("var1", "var2")],
-        recharge={0: 0.004},
+        recharge={0: 0.004, 1: []},
         aux=aux,
     )  # *** test if aux works ***
     chk = rch_package.check()
@@ -2078,6 +2078,11 @@ def test004_create_tests_bcfss(function_tmpdir, example_data_path):
     assert aux_out[0][1][0, 0] == 1.3
     assert aux_out[1][0][0, 0] == 200.0
     assert aux_out[1][1][0, 0] == 1.5
+    # write test
+    sim.set_sim_path(function_tmpdir)
+    sim.write_simulation()
+    # update recharge
+    recharge = {0: 0.004, 1: 0.004}
 
     riv_period = {}
     riv_period_array = []

flopy/mf6/data/mfdataarray.py

@@ -1788,6 +1788,9 @@ def has_data(self, layer=None):
                 self.get_data_prep(sto_key)
                 if super().has_data():
                     return True
+            for val in self.empty_keys.values():
+                if val:
+                    return True
             return False
         else:
             self.get_data_prep(layer)
@@ -1918,7 +1921,11 @@ def _set_data_record(
                 if list_item is None:
                     self.remove_transient_key(key)
                     del_keys.append(key)
+                    self.empty_keys[key] = False
+                elif isinstance(list_item, list) and len(list_item) == 0:
+                    self.empty_keys[key] = True
                 else:
+                    self.empty_keys[key] = False
                     self._set_data_prep(list_item, key)
                     if is_record:
                         super().set_record(list_item)
@@ -1940,7 +1947,11 @@ def _set_data_record(
                     key = 0
             if data is None:
                 self.remove_transient_key(key)
+            elif isinstance(data, list) and len(data) == 0:
+                # add empty record
+                self.empty_keys[key] = True
             else:
+                self.empty_keys[key] = False
                 self._set_data_prep(data, key)
                 super().set_data(data, multiplier, layer)
 
@@ -1962,6 +1973,8 @@ def get_file_entry(
 
         """
 
+        if key in self.empty_keys and self.empty_keys[key]:
+            return ""
         self._get_file_entry_prep(key)
         return super().get_file_entry(ext_file_action=ext_file_action)
 

flopy/mf6/mfpackage.py

@@ -1037,7 +1037,7 @@ def load(self, block_header, fd, strict=True):
             for ds in self.datasets.values():
                 if isinstance(ds, mfdata.MFTransient):
                     transient_key = block_header.get_transient_key()
-                    ds.set_data(empty_arr, transient_key)
+                    ds.set_data(empty_arr, key=transient_key)
         self.loaded = True
         self.is_valid()