Fix addElement to put element in proper place (#137)

In cases where the element id is a substring of another element id (but the same number of parts), it was possible for the element to be placed in the wrong location (after the element with the id its own id is a substring of).  This fixes that.

Fixes #122

src/fhirtypes/StructureDefinition.ts

@@ -119,7 +119,10 @@ export class StructureDefinition {
       const currentId = this.elements[i].id;
       if (element.id.startsWith(`${currentId}.`) || element.id.startsWith(`${currentId}:`)) {
         lastMatchId = currentId;
-      } else if (!currentId.startsWith(lastMatchId)) {
+      } else if (
+        !currentId.startsWith(`${lastMatchId}.`) &&
+        !currentId.startsWith(`${lastMatchId}:`)
+      ) {
         break;
       }
     }

test/fhirtypes/ElementDefinition.test.ts

@@ -363,6 +363,112 @@ describe('ElementDefinition', () => {
       );
     });
 
+    it('should add children in the right location when one slicename is a substring of another', () => {
+      // Tests bug reported here: https://github.com/FHIR/sushi/issues/122
+      const numOriginalElements = observation.elements.length;
+      const component = observation.elements.find(e => e.path === 'Observation.component');
+      component.slicing = {
+        ordered: false,
+        rules: 'open',
+        discriminator: [{ type: 'value', path: 'code' }]
+      };
+      // Set up the slices first
+      const fooSlice = component.addSlice('FooSlice');
+      const fooSliceBar = component.addSlice('FooSliceBar');
+      // Then unfold them
+      const newFooSliceElements = fooSlice.unfold(fisher);
+      expect(newFooSliceElements).toHaveLength(8);
+      expect(newFooSliceElements[0].id).toBe('Observation.component:FooSlice.id');
+      expect(newFooSliceElements[1].id).toBe('Observation.component:FooSlice.extension');
+      expect(newFooSliceElements[2].id).toBe('Observation.component:FooSlice.modifierExtension');
+      expect(newFooSliceElements[3].id).toBe('Observation.component:FooSlice.code');
+      expect(newFooSliceElements[4].id).toBe('Observation.component:FooSlice.value[x]');
+      expect(newFooSliceElements[5].id).toBe('Observation.component:FooSlice.dataAbsentReason');
+      expect(newFooSliceElements[6].id).toBe('Observation.component:FooSlice.interpretation');
+      expect(newFooSliceElements[7].id).toBe('Observation.component:FooSlice.referenceRange');
+      const newFooSliceBarElements = fooSliceBar.unfold(fisher);
+      expect(newFooSliceBarElements).toHaveLength(8);
+      expect(newFooSliceBarElements[0].id).toBe('Observation.component:FooSliceBar.id');
+      expect(newFooSliceBarElements[1].id).toBe('Observation.component:FooSliceBar.extension');
+      expect(newFooSliceBarElements[2].id).toBe(
+        'Observation.component:FooSliceBar.modifierExtension'
+      );
+      expect(newFooSliceBarElements[3].id).toBe('Observation.component:FooSliceBar.code');
+      expect(newFooSliceBarElements[4].id).toBe('Observation.component:FooSliceBar.value[x]');
+      expect(newFooSliceBarElements[5].id).toBe(
+        'Observation.component:FooSliceBar.dataAbsentReason'
+      );
+      expect(newFooSliceBarElements[6].id).toBe('Observation.component:FooSliceBar.interpretation');
+      expect(newFooSliceBarElements[7].id).toBe('Observation.component:FooSliceBar.referenceRange');
+      expect(observation.elements).toHaveLength(numOriginalElements + 18);
+      // Then check they are in right order, starting with plain old Observation.component
+      const componentIdx = observation.elements.findIndex(e => e.id === 'Observation.component');
+      expect(observation.elements[componentIdx + 1].id).toBe('Observation.component.id');
+      expect(observation.elements[componentIdx + 2].id).toBe('Observation.component.extension');
+      expect(observation.elements[componentIdx + 3].id).toBe(
+        'Observation.component.modifierExtension'
+      );
+      expect(observation.elements[componentIdx + 4].id).toBe('Observation.component.code');
+      expect(observation.elements[componentIdx + 5].id).toBe('Observation.component.value[x]');
+      expect(observation.elements[componentIdx + 6].id).toBe(
+        'Observation.component.dataAbsentReason'
+      );
+      expect(observation.elements[componentIdx + 7].id).toBe(
+        'Observation.component.interpretation'
+      );
+      expect(observation.elements[componentIdx + 8].id).toBe(
+        'Observation.component.referenceRange'
+      );
+      expect(observation.elements[componentIdx + 9].id).toBe('Observation.component:FooSlice');
+      expect(observation.elements[componentIdx + 10].id).toBe('Observation.component:FooSlice.id');
+      expect(observation.elements[componentIdx + 11].id).toBe(
+        'Observation.component:FooSlice.extension'
+      );
+      expect(observation.elements[componentIdx + 12].id).toBe(
+        'Observation.component:FooSlice.modifierExtension'
+      );
+      expect(observation.elements[componentIdx + 13].id).toBe(
+        'Observation.component:FooSlice.code'
+      );
+      expect(observation.elements[componentIdx + 14].id).toBe(
+        'Observation.component:FooSlice.value[x]'
+      );
+      expect(observation.elements[componentIdx + 15].id).toBe(
+        'Observation.component:FooSlice.dataAbsentReason'
+      );
+      expect(observation.elements[componentIdx + 16].id).toBe(
+        'Observation.component:FooSlice.interpretation'
+      );
+      expect(observation.elements[componentIdx + 17].id).toBe(
+        'Observation.component:FooSlice.referenceRange'
+      );
+      expect(observation.elements[componentIdx + 18].id).toBe('Observation.component:FooSliceBar');
+      expect(observation.elements[componentIdx + 19].id).toBe(
+        'Observation.component:FooSliceBar.id'
+      );
+      expect(observation.elements[componentIdx + 20].id).toBe(
+        'Observation.component:FooSliceBar.extension'
+      );
+      expect(observation.elements[componentIdx + 21].id).toBe(
+        'Observation.component:FooSliceBar.modifierExtension'
+      );
+      expect(observation.elements[componentIdx + 22].id).toBe(
+        'Observation.component:FooSliceBar.code'
+      );
+      expect(observation.elements[componentIdx + 23].id).toBe(
+        'Observation.component:FooSliceBar.value[x]'
+      );
+      expect(observation.elements[componentIdx + 24].id).toBe(
+        'Observation.component:FooSliceBar.dataAbsentReason'
+      );
+      expect(observation.elements[componentIdx + 25].id).toBe(
+        'Observation.component:FooSliceBar.interpretation'
+      );
+      expect(observation.elements[componentIdx + 26].id).toBe(
+        'Observation.component:FooSliceBar.referenceRange'
+      );
+    });
+
     it('should not add any children when an element has multiple types', () => {
       const numOriginalElements = observation.elements.length;
       const valueIdx = observation.elements.findIndex(e => e.path === 'Observation.value[x]');

test/fhirtypes/StructureDefinition.test.ts

@@ -139,6 +139,27 @@ describe('StructureDefinition', () => {
       expect(observation.elements[3].id).toBe('Observation.meta.id');
     });
 
+    it('should add an element in the right place even with substrings involved', () => {
+      // Tests bug reported here: https://github.com/FHIR/sushi/issues/122
+      observation.addElement(new ElementDefinition('Observation.component:FooBefore'));
+      observation.addElement(new ElementDefinition('Observation.component:Foo'));
+      observation.addElement(new ElementDefinition('Observation.component:FooAfter'));
+      observation.addElement(new ElementDefinition('Observation.component:Foo.id'));
+      observation.addElement(new ElementDefinition('Observation.component:FooAfter.id'));
+      observation.addElement(new ElementDefinition('Observation.component:FooBefore.id'));
+      expect(observation.elements).toHaveLength(56);
+      const getIdx = (id: string) => {
+        return observation.elements.findIndex(e => e.id === id);
+      };
+      expect(getIdx('Observation.component')).toBe(41);
+      expect(getIdx('Observation.component:FooBefore')).toBe(50);
+      expect(getIdx('Observation.component:FooBefore.id')).toBe(51);
+      expect(getIdx('Observation.component:Foo')).toBe(52);
+      expect(getIdx('Observation.component:Foo.id')).toBe(53);
+      expect(getIdx('Observation.component:FooAfter')).toBe(54);
+      expect(getIdx('Observation.component:FooAfter.id')).toBe(55);
+    });
+
     it('should add explicit choice element in the right place', () => {
       observation.addElement(new ElementDefinition('Observation.value[x]:valueQuantity'));
       expect(observation.elements).toHaveLength(51);