Tutorial 13 - Data Driven Testing in Behave BDD
Welcome to the 13th article in Behave BDD series!
What you will Learn:
Data Driven Testing using ‘Examples’ keyword and ‘Scenario Outline’
Data Driven Testing using ‘Examples’ keyword and ‘Scenario Outline’
For data driven testing, we need the help of ‘Examples’ keyword and ‘Scenario Outline’. These 2 go hand-in-hand. You cannot use ‘Examples’ keyword with normal ‘Scenario’ that we have been writing so far.
Let us create a brand new ‘Login’ feature feature file
The ‘Examples’ table acts like a test data table for us. It contains multiple set of test data to test our application
Now, in the above ‘Scenario Outline’, look at line numbers 7 and 8. We have written “<Username>” and “<Password>”. So these are string values because these are written within double quotes
Now, the <Username> that you see in the figure above is actually the column name that we have written in the ‘Examples’ table. Similar is the case with <Password>. These should be an exact match. You cannot write <Username> in line number 7 and USERNAME in ‘Examples’ table. 
So the entire scenario will be executed 2 times since we have 2 rows in our ‘Examples’ table
So, this is the concept of data driven testing.
Let us see a practical example using selenium.
Write the feature file as see below
Save the file
Write the step definition file
Run the feature file
Notice the console output. The scenario got executed twice. The username/password was picked up from the ‘Examples’ table.
Also, 10 steps got passed since we have 5 steps in a scenario. This would be multiplied by 2 rows in the table, hence 10 steps.
So, testuser3@gmail.com/ testuser3 was picked up in first scenario execution and testuser4@gmail.com/ testuser4 was picked up in second scenario execution
Below are the screenshots during run execution. As you notice, the first firefox browser executes the first set of test data. Once this gets over, another firefox browser opens to execute 2nd set of data
Another browser opens
This is how we perform data driven testing using behave.
Thank you for reading!