What the difference between "step" and "next" in "byebug".
When should one use one over the other?
step: Step execution into the next line or method. Takes an optional numeric argument to step multiple times.
next: Step over to the next line within the same frame. Also takes an optional numeric argument to step multiple lines.
Please check through pry-byebug gem documentation for futher details:
https://github.com/deivid-rodriguez/pry-byebug#commands
Related
What is the difference between "step over" and "step over expression" in debugging of NetBeans? I have clicked on both of them, but I can't find a difference?
From Netbeans wiki:
Step Over Expression enables you to proceed through each method call in an expression and view the input parameters as well as resulting output values of each method call (...) If there are no further method calls, Step Over Expression behaves like the Step Over command.
If we use Step Over Expression, we will see input/ output of expression. In this image, I have expression String name = debug.getName("A") + debug.getName("B");.
When run we will see in image.
But with Step Over is not. We only see value of name.
According to NetBeans 6 in Simple Steps (p. 193),
Step Over (F8): Executes the current line then moves to the next line.
If any line contains call to a method or constructor then executes the
entire method or constructor without stepping into them.
Step Over Expression (SHIFT+F8): Steps through an expression and view
the value of each method call in the expression. If a line has
multiple calls to the methods or constructors, you can use the Step
Over Expression. The Step Over Expression command performs like Step
Over command if there are no multiple method calls.
What is the actual syntax for writing step definitions in Cucumber? I have seen it being written in different ways. Is there no definite syntax? I know the anchors are not compulsory, but is there a basic rule?
I am new to Cucumber and will appreciate baby step information to help me understand the basics. Thanks guys!
I was planning to point you to online documentation, but the online documentation I know about (at cucumber.io and at relishapp.com) doesn't actually answer your question well. (It does contain many examples, though, and is well worth reading.)
In the Ruby implementation of Cucumber, step definition files are .rb files in the features/step_definition directory. They contain a series of calls to methods that each define an implementation of a Gherkin step. Here's an example:
Given /^there is a user named "(.*)"$/ do |username|
# code that creates a user with the given username
end
There are several methods that define steps: Given, When, Then, And and But. They all do exactly the same thing, and you can use any one to define any step. The best practice is to use the one that reads best with the step you're defining (never And or But).
The argument passed to the step-defining method is a regular expression intended to match one or more steps in Gherkin .feature files. The above example matches the following step:
Given there is a user named "Ade Tester"
("Ade Tester" could be anything).
The block passed to the step-defining method is run when Cucumber executes a step which the regular expression matches. It can contain any Ruby code you like.
Matching groups (enclosed in parentheses) in the regular expression are passed to the block as block parameters. The number of matching groups must match the number of block parameters, or you'll get an error. A common convention is to enclose matching groups that match strings in quotes to visually separate them from the fixed part of the step, as I did above, but this is purely convention and you can choose not to do it.
The regexp need not match the entire step by default. If you want a definition to match only the entire step you must enforce that in the regular expression, as I did in the example above with ^ and $. Do that unless you have a good reason not to. This step definition (without $)
Given /^there is a user named "(.*)"/ do |username|
create :user, username: username
end
would match
Given there is a user named "Ade Tester" on weekdays but "Dave Schweisguth" on weekends
which would probably be a bad idea. Worse, if you had definitions for both steps, Cucumber would not be able to tell which definition to use and you'd get an error.
In features/step_definitions/documentation.rb:
When /^I go to the "([^"]+)" documentation$/ do |section|
path_part =
case section
when "Documentation"
"documentation"
else
raise "Unknown documentation section: #{section}"
end
visit "/documentation/#{path_part}/topics"
end
Then /^I should see the "([^"]+) documentation"$/ do |section|
expect(page).to have_css('h2.doctag_title a', text: section)
end
These steps exercise a web application. They are about as simple as they can be while still being practical.
A good step definition should have in its block a single method call e.g.
When "Frank logs in" do
login user: #frank
end
Bad step definitions have lots of code in their block e.g
When "I login as Frank" do
visit root_path
fill_in login_email, with:
# lots of other stuff about HOW to login
...
end
Other bad step definitions use really complicated regex's with lots of arguments.
Terrible step definitions call other step definitions and do the things bad step definitions do.
This is a basic question on the use of Trace Tables to assist in a dry run of a simple algorithm.
What I find most tricky is when to take a new line in the trace table? For example, take the following question:
Here is the array of integers which it applies to:
The following trace table is presented as one completes a dry run. Here is the solution:
I understand that initialising the variables Number, Lower & Upper appear on the first line, but when I go into the While Loop, I am tempted to put the value 5 on the first line also, for the variable Current. In essence, this is what I am tempted to do:
Why does this solution require that the value for Current, which is 5, appear on the second line? I suppose the question could be rephrased to 'When do I take a new line in a trace table?'
Thanks.
I think there is no specific way to do trace table, which means you have to setup your rules before you work and go on.
consider this example:
and this also:
did you notice the difference between loop iterator in each one. In first example they put the initialization value of the iterator in first line, and in second example they put the initialization of the loop iterator in the second line.
also have a look at wiki they also put the loop initialization in the second line.
also this video has similar example to those I posted here and is always start loop iterator in the second line.
also this example has totally different approach, which is each line of code in a new line in the trace table.
you can find also another different approach for trace table here
Finally:
In my opinion chose the rules that make sense for you, for example:
1-first line will contain the default values for the variables.
2-regarding loop iterations, put loop iterator in the same line as the variables that affected by this iteration, like the second example I posted above.
regarding your question I think it's more clear to put Current first value 5 in the second line, so you can track what each loop iteration affect your variables in a clear way.
...
BREAKPOINT `int i = 10 + 12;`
...
When I add a break point to code in Android Studio as above, AS will run to the line I added the break point to, as expected. However, if there is no code after the break point line I can't see what i resolves to in the debugger. I can fix this problem by inserting a single line of dummy code, but there must be an easier/more elegant way to get around this problem that I'm missing.
How can I avoid adding a dummy line of code to view these values?
EDIT: I'm using the latest version of Android Studio (1.0.2)
It's possible to put a breakpoint on the line following the last line you want executed.
A breakpoint stops execution before the line under the breakpoint is executed.
In the example above, a new variable is introduced (i), which is as yet unknown to the interpreter. It's necessary to step-over (execute) the line of code in order for this variable to be initialized.
See the example below, in which there's a test function that contains the line of code from the question:
I've put breakpoints on the start brace of the function {, the line in question, and the end brace }. Note that there's an X on the first breakpoint, as it's invalid. The current execution point is on (or just before execution of) the dark-blue highlited line. Note that the variable i does not exist in the Variables window below.
When I step over (execute) the line of code, the active line is now over the final brace in the function }, and that the variable i is now initialized and set:
So, if you're interested in breaking after a given line of code, just put the breakpoint after that line of code, even if that line is the final brace of a function.
Note: this won't work if there is an exit statement (e.g. break, return etc.) as the final executed line of code in a function.
So I have a keyword driven framework that executes on keywords. In one of the functions I have a if element exist condition. Now if that element doesn't exist I want qtp to not execute the next 3 keyword functions following it. Is there a way to do this? Thank you!
You could a global variable that records the number of keywords that should be skipped. When your element doesn't exist, you could set the skip count to 3. In your framework that reads each keyword, you could first check the current skip count. If it's 0, you execute the keyword normally. Otherwise, you decrease the skip count by 1 and exit without executing that keyword.
Can you not insert a conditional statement?
Therefore if the element exists, you can put the next 3 statements within the loop? Else, do nothing. Then have the code follow on as normal?
If you aren't comfortable in expert view, this shows how to do it in keyword view also:
http://www.softwaretestinghelp.com/conditional-loop-statements-qtp-tutorial-4/