Overhaul the query history tab to allow browsing of the history and full query text. Fixes #2282

Patch by Joao and the team at Pivotal.

web/regression/javascript/code_mirror_spec.jsx

@@ -0,0 +1,68 @@
+/////////////////////////////////////////////////////////////
+//
+// pgAdmin 4 - PostgreSQL Tools
+//
+// Copyright (C) 2013 - 2017, The pgAdmin Development Team
+// This software is released under the PostgreSQL Licence
+//
+//////////////////////////////////////////////////////////////
+
+import React from 'react';
+import $ from '../../pgadmin/static/vendor/jquery/jquery-1.11.2';
+import CodeMirror from '../../pgadmin/static/jsx/history/detail/code_mirror';
+import jasmineEnzyme from 'jasmine-enzyme';
+
+import {shallow} from 'enzyme';
+
+
+describe('CodeMirror', () => {
+  beforeEach(() => {
+    jasmineEnzyme();
+  });
+
+  describe('#hydrateWhenBecomesVisible', () => {
+    let codeMirror, isVisibleSpy;
+
+    beforeEach(() => {
+      codeMirror = shallow(<CodeMirror />).instance();
+      isVisibleSpy = spyOn($.fn, 'is');
+      spyOn(codeMirror, 'hydrate');
+    });
+
+    describe('when component is visible', () => {
+      beforeEach(() => {
+        isVisibleSpy.and.returnValue(true);
+      });
+
+      it('should hydrate the codemirror element', () => {
+        codeMirror.hydrateWhenBecomesVisible();
+        expect(codeMirror.hydrate).toHaveBeenCalledTimes(1);
+      });
+    });
+
+    describe('when component is not visible', () => {
+      beforeEach(() => {
+        isVisibleSpy.and.returnValue(false);
+      });
+
+      it('should not hydrate the codemirror element', () => {
+        codeMirror.hydrateWhenBecomesVisible();
+        expect(codeMirror.hydrate).not.toHaveBeenCalled();
+      });
+
+      describe('when becomes visible', () => {
+        beforeEach(() => {
+          isVisibleSpy.and.returnValue(true);
+        });
+
+        it('should hydrate the codemirror element', (done) => {
+          setTimeout(() => {
+            codeMirror.hydrateWhenBecomesVisible();
+            expect(codeMirror.hydrate).toHaveBeenCalledTimes(1);
+            done();
+          }, 150);
+        });
+      });
+    });
+  });
+});