Fix __init__ signals when using attributes={'_lazy':True} as keywor…

…d argument

hyperspy/_signals/lazy.py

@@ -160,9 +160,8 @@ def __init__(self, *args, **kwargs):
         # the NumPy array originates from.
         self._cache_dask_chunk = None
         self._cache_dask_chunk_slice = None
-        if hasattr(self, "events"):
-            if not self._clear_cache_dask_data in self.events.data_changed._connected_all:
-                self.events.data_changed.connect(self._clear_cache_dask_data)
+        if not self._clear_cache_dask_data in self.events.data_changed.connected:
+            self.events.data_changed.connect(self._clear_cache_dask_data)
 
     def compute(self, close_file=False, show_progressbar=None, **kwargs):
         """Attempt to store the full signal in memory.
@@ -272,9 +271,7 @@ def _get_file_handle(self, warn=True):
                                     "an hdf5 file.")
 
     def _clear_cache_dask_data(self, obj=None):
-        if self._cache_dask_chunk is not None:
-            del self._cache_dask_chunk
-            self._cache_dask_chunk = None
+        self._cache_dask_chunk = None
         self._cache_dask_chunk_slice = None
 
     def _get_dask_chunks(self, axis=None, dtype=None):
@@ -498,8 +495,8 @@ def _get_cache_dask_chunk(self, indices):
         chunks = self._get_navigation_chunk_size()
         navigation_indices = indices[:-sig_dim]
         chunk_slice = _get_navigation_dimension_chunk_slice(navigation_indices, chunks)
-        if chunk_slice != self._cache_dask_chunk_slice:
-            self._clear_cache_dask_data()
+        if (chunk_slice != self._cache_dask_chunk_slice or
+                self._cache_dask_chunk is None):
             self._cache_dask_chunk = np.asarray(self.data.__getitem__(chunk_slice))
             self._cache_dask_chunk_slice = chunk_slice
 

hyperspy/_signals/signal2d.py

@@ -954,6 +954,3 @@ def find_peaks(self, method='local_max', interactive=True,
 class LazySignal2D(LazySignal, Signal2D):
 
     _lazy = True
-
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)

hyperspy/signal.py

@@ -2180,7 +2180,6 @@ class for more details).
             self.models = ModelManager(self)
             self.learning_results = LearningResults()
             kwds['data'] = data
-            self._load_dictionary(kwds)
             self._plot = None
             self.inav = SpecialSlicersSignal(self, True)
             self.isig = SpecialSlicersSignal(self, False)
@@ -2198,6 +2197,7 @@ class for more details).
                 Arguments:
                     obj: The signal that owns the data.
                 """, arguments=['obj'])
+            self._load_dictionary(kwds)
 
     def _create_metadata(self):
         self.metadata = DictionaryTreeBrowser()
@@ -5332,13 +5332,16 @@ def get_current_signal(self, auto_title=True, auto_filename=True):
                         key_dict[key] = marker.get_data_position(key)
                     marker.set_data(**key_dict)
 
-        cs = self.__class__(
+        class_ = hyperspy.io.assign_signal_subclass(
+            dtype=self.data.dtype,
+            signal_dimension=self.axes_manager.signal_dimension,
+            signal_type=self._signal_type,
+            lazy=False)
+
+        cs = class_(
             self(),
             axes=self.axes_manager._get_signal_axes_dicts(),
             metadata=metadata.as_dictionary())
-        if self._lazy:
-            cs._lazy = False
-            cs._assign_subclass()
 
         if cs.metadata.has_item('Markers'):
             temp_marker_dict = cs.metadata.Markers.as_dictionary()

hyperspy/tests/signals/test_assign_subclass.py

@@ -199,3 +199,8 @@ def test_complex_to_dielectric_function(self):
         assert isinstance(self.s, hs.signals.DielectricFunction)
         self.s.set_signal_type("")
         assert isinstance(self.s, hs.signals.ComplexSignal1D)
+
+
+def test_create_lazy_signal():
+    # Check that this syntax is working
+    _ = hs.signals.BaseSignal([0, 1, 2], attributes={'_lazy': True})

hyperspy/tests/signals/test_tools.py

@@ -24,7 +24,6 @@
 
 from hyperspy import signals
 from hyperspy.decorators import lazifyTestClass
-from hyperspy.signal_tools import SpikesRemoval, SpikesRemovalInteractive
 
 
 def _verify_test_sum_x_E(self, s):