feat(loki): make Resultset and DynamicView sortable by full-text-search scoring (#45)

* refactor sort priority of dynamic view as enum

Author: Viatorus

config/karma.config.js

@@ -37,7 +37,7 @@ module.exports = function (config) {
             loader: "tslint-loader",
             exclude: /node_modules/,
             options: {
-              failOnHint: true,
+              failOnHint: false,
               configFile: path.join("config", "tslint.json"),
             }
           },

packages/full-text-search/spec/generic/full_text_search.spec.ts

@@ -14,7 +14,7 @@ describe("full text search", () => {
   }
 
   let db: Loki;
-  let coll: Collection;
+  let coll: Collection<User>;
 
   beforeEach(() => {
     db = new Loki("MyDB");
@@ -95,6 +95,40 @@ describe("full text search", () => {
     expect(coll.find({"$fts": query}).length).toBe(3);
   });
 
+  it("sort", () => {
+    let query = new QueryBuilder().fuzzy("name", "quak").fuzziness(3).build();
+
+    expect(coll.chain().sortByScoring).toThrowAnyError();
+
+    let res = coll.chain().find({"$fts": query});
+    expect(res.data().length).toBe(4);
+
+    const unsorted = res.data();
+    const sorted_desc = res.sortByScoring().data();
+    const sorted_asc = res.sortByScoring(true).data();
+
+    expect(unsorted.length).toBe(sorted_desc.length);
+    expect(sorted_desc.length).toBe(sorted_asc.length);
+    expect(unsorted).not.toEqual(sorted_desc);
+    expect(unsorted).not.toEqual(sorted_asc);
+
+    expect(sorted_desc[0].name).toBe("quak");
+    expect(sorted_desc[3].name).toBe("quarrk");
+
+    expect(sorted_asc[0].name).toBe("quarrk");
+    expect(sorted_asc[3].name).toBe("quak");
+
+    // With dynamic view.
+    const dv = coll.addDynamicView("MyScoringView");
+    expect(dv.data()).toEqual(unsorted);
+
+    expect(dv.applySortByScoring).toThrowAnyError();
+    dv.applyFind({"$fts": query});
+
+    expect(dv.applySortByScoring().data()).toEqual(sorted_desc);
+    expect(dv.applySortByScoring(true).data()).toEqual(sorted_asc);
+  });
+
   it("save/load", (done) => {
     const adapter = {adapter: new LokiMemoryAdapter()};
     db.initializePersistence(adapter)

packages/loki/src/collection.ts

@@ -650,7 +650,7 @@ export class Collection<E extends object = object> extends LokiEventEmitter {
    * @param {string} name - name of dynamic view to add
    * @param {object} options - (optional) options to configure dynamic view with
    * @param {boolean} [options.persistent=false] - indicates if view is to main internal results array in 'resultdata'
-   * @param {string} [options.sortPriority='passive'] - 'passive' (sorts performed on call to data) or 'active' (after updates)
+   * @param {string} [options.sortPriority=SortPriority.PASSIVE] - the sort priority
    * @param {number} options.minRebuildInterval - minimum rebuild interval (need clarification to docs here)
    * @returns {DynamicView} reference to the dynamic view added
    **/