test: refactor list collections unit test

Author: durran

src/operations/list_collections.ts

@@ -90,14 +90,17 @@ export class ListCollectionsOperation extends CommandOperation<string[]> {
       return;
     }
 
-    const command = {
+    return super.executeCommand(server, session, this.generateCommand(), callback);
+  }
+
+  /** @internal */
+  generateCommand(): Document {
+    return {
       listCollections: 1,
       filter: this.filter,
       cursor: this.batchSize ? { batchSize: this.batchSize } : {},
       nameOnly: this.nameOnly
     };
-
-    return super.executeCommand(server, session, command, callback);
   }
 }
 

test/functional/unit_db_list_collections.test.js

@@ -0,0 +1,79 @@
+'use strict';
+
+const { expect } = require('chai');
+const { ListCollectionsOperation } = require('../../../src/operations/list_collections');
+
+describe('ListCollectionsOperation', function () {
+  const db = 'test';
+
+  describe('#constructor', function () {
+    context('when nameOnly is provided', function () {
+      context('when nameOnly is true', function () {
+        const operation = new ListCollectionsOperation(db, {}, { nameOnly: true, dbName: db });
+
+        it('sets nameOnly to true', function () {
+          expect(operation.nameOnly).to.be.true;
+        });
+      });
+
+      context('when nameOnly is false', function () {
+        const operation = new ListCollectionsOperation(db, {}, { nameOnly: false, dbName: db });
+
+        it('sets nameOnly to false', function () {
+          expect(operation.nameOnly).to.be.false;
+        });
+      });
+    });
+
+    context('when nameOnly is not provided', function () {
+      const operation = new ListCollectionsOperation(db, {}, { dbName: db });
+
+      it('sets nameOnly to false', function () {
+        expect(operation.nameOnly).to.be.false;
+      });
+    });
+  });
+
+  describe('#generateCommand', function () {
+    context('when nameOnly is provided', function () {
+      context('when nameOnly is true', function () {
+        const operation = new ListCollectionsOperation(db, {}, { nameOnly: true, dbName: db });
+
+        it('sets nameOnly to true', function () {
+          expect(operation.generateCommand()).to.deep.equal({
+            listCollections: 1,
+            cursor: {},
+            filter: {},
+            nameOnly: true
+          });
+        });
+      });
+
+      context('when nameOnly is false', function () {
+        const operation = new ListCollectionsOperation(db, {}, { nameOnly: false, dbName: db });
+
+        it('sets nameOnly to false', function () {
+          expect(operation.generateCommand()).to.deep.equal({
+            listCollections: 1,
+            cursor: {},
+            filter: {},
+            nameOnly: false
+          });
+        });
+      });
+    });
+
+    context('when nameOnly is not provided', function () {
+      const operation = new ListCollectionsOperation(db, {}, { dbName: db });
+
+      it('sets nameOnly to false', function () {
+        expect(operation.generateCommand()).to.deep.equal({
+          listCollections: 1,
+          cursor: {},
+          filter: {},
+          nameOnly: false
+        });
+      });
+    });
+  });
+});