Selecting a regulon causes an infinite loop in the backend

[KrisDavie]

After selecting a regulon on the regulon tab, after loading the 3 plotsm the backend ends up in a (possibly) infinite loop reloading the loom file and causes performance issues.

[dweemx]

This issue is not trivial and is in fact a double infinite loop each triggered by a listener function call.

When a user select a result from the Search results, it dispatches the following action:

SCope/src/components/Search/FeatureSearchBox.tsx

Line 117 in 3821798

dispatch(Action.select(props.field, selection));

This will render the FeatureSearchBox component and since selected is now defined, Legacy.updateFeature will be called:

SCope/src/components/Search/FeatureSearchBox.tsx

Lines 158 to 164 in 3821798

	LegacyAPI.updateFeature(
	legacyFeatureIndex,
	props.filter,
	state.selected.title,
	state.selected.category,
	state.selected.description
	);

The two problematic listeners are getting called inside setActiveFeature function:

SCope/src/components/common/API.jsx

Lines 424 to 428 in 69a2bff

	this.getMaxScale(featureId, (customValues, maxValues) => {
	(this.featureChangeListeners[page] || []).forEach((listener) => {
	listener(selectedFeatures, featureId, customValues, maxValues);
	});
	});

and are the following:

• From Regulon.jsx:
  

  SCope/src/components/pages/Regulon.jsx

  Lines 26 to 28 in 3821798

  	this.activeFeaturesListener = (features, featureID) => {
  	this.setState({ activeFeatures: features });
  	};

• From ViewSideBar.jsx:
  

  SCope/src/components/common/ViewerSidebar.jsx

  Lines 60 to 67 in 3821798

  	this.activeFeaturesListener = (features, id) => {
  	this.props.onActiveFeaturesChange(features, id);
  	console.log('ViewerSidebar features changed:', features, id);
  	this.setState({
  	activeFeatures: features,
  	activeTab: parseInt(id) + 1,
  	});
  	};

Each of them will trigger a re-render of FeatureSearchBox and since !R.equals(currentFeature, legacyFeature) is true:

hence the infinite loop

[MaybeJustJames]

Fixed in #451