Add methods getOrDefault and getOrThrow

src/Model/collections.ts

@@ -77,16 +77,17 @@ declare module './Model' {
     getOrCreateDoc(collectionName: string, id: string, data: any);
 
     /**
-     * Get a value that may be undefined but ensure value is returned
+     * Gets value at the path if not nullish, otherwise returns provided default value
      *
      * @param subpath
      * @param defaultValue value to return if no value at subpath
      */
     getOrDefault<S>(subpath: Path, defaultValue: S): ReadonlyDeep<S>;
 
     /**
-     * Get a value and throw error if undefined
+     * Gets the value located at this model's path or a relative subpath.
      *
+     * If no value exists at the path, or the value is nullish (null or undefined), this will throw an error.
      * @param subpath
      */
     getOrThrow<S>(subpath: Path): ReadonlyDeep<S>;
@@ -174,8 +175,8 @@ Model.prototype.getOrDefault = function<S>(subpath: Path, defaultValue: S) {
 
 Model.prototype.getOrThrow = function<S>(subpath?: Path) {
   const value = this.get(subpath);
-  if (value === undefined) {
-    const fullpath = [this._at, subpath].filter(Boolean).join('.');
+  if (value == null) {
+    const fullpath = this.path(subpath);
     throw new Error(`No value at path ${fullpath}`)
   }
   return value;

test/Model/collections.js

@@ -18,20 +18,37 @@ describe('collections', () => {
       expect(value.name).to.equal('bar');
       expect(value).to.eql(defaultValue);
     });
+
+    it('returns defult value if null', () => {
+      const model = new RootModel();
+      const id = model.add('_test_doc', {name: null});
+      const defaultValue = 'bar';
+      const value = model.getOrDefault(`_test_doc.${id}.name`, defaultValue);
+      expect(value).not.to.be.null;
+      expect(value).to.equal('bar');
+      expect(value).to.eql(defaultValue);
+    });
   });
 
   describe('getOrThrow', () => {
     it('returns value if defined', () => {
       const model = new RootModel();
       model.add('_test_doc', {name: 'foo'});
-      const value = model.getOrThrow('_test_doc', {name: 'bar'});
+      const value = model.getOrThrow('_test_doc');
       expect(value).not.to.be.undefined;
     });
 
-    it('thows if value undefined', () => {
+    it('throws if value undefined', () => {
+      const model = new RootModel();
+      expect(() => model.getOrThrow('_test_doc')).to.throw(`No value at path _test_doc`);
+      expect(() => model.scope('_test').getOrThrow('doc.1')).to.throw(`No value at path _test.doc.1`);
+    });
+
+    it('throws if value null', () => {
       const model = new RootModel();
-      expect(() => model.getOrThrow('_test_doc', {name: 'bar'})).to.throw(`No value at path _test_doc`);
-      expect(() => model.scope('_test').getOrThrow('doc.1', {name: 'bar'})).to.throw(`No value at path _test.doc.1`);
+      const id = model.add('_test_doc', {name: null});
+      expect(model.getOrThrow(`_test_doc.${id}`)).to.eql({id, name: null});
+      expect(() => model.getOrThrow(`_test_doc.${id}.name`)).to.throw(`No value at path _test_doc`);
     });
   });
 });