Monday, September 12, 2016

QA: Decision Tables as specification-based test design technique

Let's start with definitions, per ISTQB glossary:
Decision Table Testing: A black-box test design technique in which test cases are designed to execute the combinations of inputs and/or stimuli (causes) shown in a decision table.
Decision Table: A table showing combinations of inputs and/or stimuli (causes) with their associated outputs and/or actions (effects), which can be used to design test cases.
This technique is using to test all possible combination of conditions, relationships, and constraints. Decision tables usually applied for the integration, system and acceptance test levels. Also, this technique could be used for component testing.
The table should describe relationships between conditions and actions.

Template of Decision Table:
Decision Table Template

Decision Table Example

At least one test case should be created for each column. The number of tests will increase in case of boundaries values in conditions. Boundary Value Analysis and Equivalence Partitioning are additional to the Decision Table technique

Type of defects: functional and non-functional defects

Wednesday, September 7, 2016

Setting up Visual Studio Code for TypeScript development

Install TypeScript compiler

To setup TypeScript on your computer, you need to setup node.js with npm. There is a good article, which will help you to do that, please find it using following link: Installing Node.js and updating npm. 
We just installed node.js and updated npm. So we are ready to install TypeScript on your computer. If you want you can install the latest build of TypeScript. To do that you have to run following command:

npm install -g typescript@next #install nightly build

Although you have the possibility to install nightly builds, I would recommend installing the latest stable version of the language. To do that type following command in cmd.exe and hit enter:

npm install -g typescript #install the latest stable version

Install Visual Studio Code with extensions

GulpTsLintVisual Studio Code

Visual Studio Code

Let's install Visual Studio Code first. You can download and install it from


An extensible linter for the TypeScript language. TSLint supports:
  • custom lint rules
  • custom formatters (failure reporters)
  • inline disabling / enabling of rules
  • configuration presets (tslint:latest, tslint-react, etc.) & composition
For more info please use

To install TSLint extension: Open Visual Studio Code → Navigate to Extensions tab on left sidebar → Type 'TsLint' in search text-box → Install extension.

To make extension work you need to install tslint globally. To do that run in cmd.exe tool the command:

npm install -g tslint #installing tslint globally

Gulp Snippets

We are going to use Gulp to compile our TypeScript code, so let's install Visual Studio Code extension to help us with Gulp syntax.
Open Visual Studio Code → Navigate to Extensions tab on left sidebar → Type 'Gulp Snippets' in search text-box → Install extension.

Creating the project

First of all, you need to create the project folder. I will create mine with the name "TypeScriptBlog". Create the folder and open it in cmd.exe tool. Now we need to create package.json file. To do that run in cmd.exe command:

cd path/to/project
npm init

Open created folder in Visual Studio Code and check created file. It should contain something like this:

  "name": "typescriptblog",
  "version": "1.0.0",
  "description": "Blog engine written on TypeScript",
  "main": "main.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  "author": "",
  "license": "MIT"

We are now ready to install the third party dependencies:

npm install  --save-dev typescript
npm install  --save-dev tslint 
npm install  --save-dev gulp
npm install  --save-dev gulp-tslint
npm install  --save-dev gulp-typescript

Compiling the project

Create gulpfile.js in the project's  folder and copy following  content to it:

var gulp = require("gulp"),
    tslint = require("gulp-tslint"),
    tsc = require("gulp-typescript");

var tsProject = tsc.createProject("tsconfig.json");

gulp.task("build-app", function () {
    return gulp.src([

// Rebuild project on any ts file changed
gulp.task('watch', function() {"app/**/**.ts", ['build-app']);

Create tsconfig.json file and copy following content to it:

    "compilerOptions": {
        "sourceMap":  true

Now we can build our application. Press Ctrl + Shift + P in Visual Studio Code → Type "Run Task" → run "build-app" task. If you want to rebuild your code each time when any file changed, execute task with name "watch".

To test that the Gulp is working you can use following files. Create app folder in the root folder and add files to app folder.


class Greeter {
    constructor(public greeting: string) { }
    greet() {
        return "<h1>" + this.greeting + "</h1>";

var greeter = new Greeter("Hello, world!");
document.body.innerHTML = greeter.greet();


<!DOCTYPE html>
  <head><title> TypeScript Greeter </title></head>
    <script src='greeter.js'></script>

Project structure

Linting the project

Earlier we installed all necessary tools for linting. Now it is time to configure them. Open cmd.exe and execute command:

cd path/to/project
tslint --init

After that you can find that tslint.json file was added to the solution. This file contains default linting settings, if you would like to extend or change them, please use for more info.
One more thing what we can do. We want tslint be executed using Gulp, so open gulpfile.js file and add the following code to it:

// Linting the project
gulp.task("lint", function () {
    return gulp.src([
            formatter: "verbose"

If 'lint' task does not appear in the task list, restart Visual Studio Code and try again.


Now we know how to setup Visual Studio Code with TypeScript. With this article, I open a cycle of articles about TypeScript, in which we are going to create blog engine written on TypeScript. All the code you can find under repository

Thursday, September 1, 2016

QA: Boundary Value Analysis as specification-based test design technique

Let start from definition, per ISTQB glossary:
Boundary value analysis (BVA): a black-box design technique in which test cases are designed based on boundary values.
 Boundary Value: an input or output value which is an the edge of an equivalence partition or at the smallest incremental distance on either side of an edge, for example the minimum and maximum value of a range
This technique is an extension of equivalence partitioning technique.  There are two approaches of BVA exists:
  • Two values testing.  Only two values selected for each boundary: one value on the boundary and the previous/following value outside the partition. For example, if an equivalent partition is integer range from 10 to 15, the following values should be tested: 9 (outside of the partition), 10 (boundary); 15 (boundary), 16 (outside of partition). Short description: MIN-1; MIN; MAX; MAX+1; Where "1" is the minimal incremental value
  • Three values testing. This approach uses 3 value as the basis. One value outside of the boundary, the second value is boundary value, and the third value is inside of partition. For example, if the equivalent partition is an integer from 10 to 15, the following value should be tested: 9 (outside of the partition), 10 (boundary), 11 (inside of boundary); 14 (inside of boundary), 15 (boundary), 16 (outside of partition).Short description: MIN-1; MIN; MIN+1; MAX-1; MAX; MAX+1; Where "1" is the minimal incremental value 
Which approach to select? The approach should be selected based on Risks which are associated to tested items. 3-values approach should be selected for the highest risks.
VBA could be applied for ONLY for ordered equivalent partitions. Type of ordered equivalent partitions:
  • Numeric attributes of non-numeric variables (e.g., length) 
  • Loops, including those in use cases 
  • Stored data structures 
  • Physical objects (including memory) 
  • Time-determined activities

Type of defects: functional and non-functional