check for empty Structures

src/mol-model-props/pdbe/themes/structure-quality-report.ts

@@ -31,7 +31,7 @@ const ValidationColorTable: [string, Color][] = [
 export function StructureQualityReportColorTheme(ctx: ThemeDataContext, props: {}): ColorTheme<{}> {
     let color: LocationColor
 
-    if (ctx.structure && ctx.structure.models[0].customProperties.has(StructureQualityReport.Descriptor)) {
+    if (ctx.structure && !ctx.structure.isEmpty && ctx.structure.models[0].customProperties.has(StructureQualityReport.Descriptor)) {
         const getIssues = StructureQualityReport.getIssues;
         color = (location: Location) => {
             if (StructureElement.isLocation(location)) {

src/mol-model-props/rcsb/themes/assembly-symmetry-cluster.ts

@@ -47,7 +47,7 @@ export function AssemblySymmetryClusterColorTheme(ctx: ThemeDataContext, props:
 
     const { symmetryId } = props
 
-    if (ctx.structure && ctx.structure.models[0].customProperties.has(AssemblySymmetry.Descriptor)) {
+    if (ctx.structure && !ctx.structure.isEmpty && ctx.structure.models[0].customProperties.has(AssemblySymmetry.Descriptor)) {
         const assemblySymmetry = AssemblySymmetry.get(ctx.structure.models[0])!
 
         const s = assemblySymmetry.db.rcsb_assembly_symmetry
@@ -99,5 +99,5 @@ export const AssemblySymmetryClusterColorThemeProvider: ColorTheme.Provider<Asse
     factory: AssemblySymmetryClusterColorTheme,
     getParams: getAssemblySymmetryClusterColorThemeParams,
     defaultValues: PD.getDefaultValues(AssemblySymmetryClusterColorThemeParams),
-    isApplicable: (ctx: ThemeDataContext) => !!ctx.structure && ctx.structure.models[0].customProperties.has(AssemblySymmetry.Descriptor)
+    isApplicable: (ctx: ThemeDataContext) => !!ctx.structure && !ctx.structure.isEmpty && ctx.structure.models[0].customProperties.has(AssemblySymmetry.Descriptor)
 }

src/mol-model/structure/structure/structure.ts

@@ -72,6 +72,10 @@ class Structure {
         return prc && ec ? ec / prc < 2 : false
     }
 
+    get isEmpty() {
+        return this.units.length === 0;
+    }
+
     get hashCode() {
         if (this._props.hashCode !== -1) return this._props.hashCode;
         return this.computeHash();

src/mol-plugin/behavior/dynamic/custom-props/pdbe/structure-quality-report.ts

@@ -40,7 +40,7 @@ export const PDBeStructureQualityReport = PluginBehavior.create<{ autoAttach: bo
                 factory: StructureQualityReportColorTheme,
                 getParams: () => ({}),
                 defaultValues: {},
-                isApplicable: (ctx: ThemeDataContext) => !!ctx.structure && ctx.structure.models[0].customProperties.has(StructureQualityReport.Descriptor)
+                isApplicable: (ctx: ThemeDataContext) => !!ctx.structure && !ctx.structure.isEmpty && ctx.structure.models[0].customProperties.has(StructureQualityReport.Descriptor)
             })
         }