feat(loki): rename collection (#32)

(from techfort/LokiJS#611)

Author: Viatorus

packages/loki/spec/generic/collection.spec.js

@@ -31,6 +31,20 @@ describe("collection", () => {
     expect(coll.data.length).toEqual(1);
   });
 
+  it("collection rename works", function () {
+    const db = new loki("test.db");
+    db.addCollection("coll1");
+
+    let result = db.getCollection("coll1");
+    expect(result.name).toEqual("coll1");
+
+    db.renameCollection("coll1", "coll2");
+    result = db.getCollection("coll1");
+    expect(result).toBeNull();
+    result = db.getCollection("coll2");
+    expect(result.name).toEqual("coll2");
+  });
+
   it("findAndUpdate works", () => {
     const db = new loki("test.db");
     const coll = db.addCollection("testcoll");

packages/loki/src/loki.js

@@ -283,6 +283,21 @@ export class Loki extends LokiEventEmitter {
     return null;
   }
 
+  /**
+   * Renames an existing loki collection
+   * @param {string} oldName - name of collection to rename
+   * @param {string} newName - new name of collection
+   * @returns {Collection} reference to the newly renamed collection
+   */
+  renameCollection(oldName, newName) {
+    const c = this.getCollection(oldName);
+    if (c) {
+      c.name = newName;
+    }
+    
+    return c;
+  }
+
   listCollections() {
     let i = this.collections.length;
     const colls = [];