So here's the anti traceback we get the assertion error, we get the assertion that failed.

The assertion cannot fail.

Therefore, the assertion would fail.

Therefore, the assertion would hold.

The assertion in the end passes.

There is identification the built in assertion typically tells you which assertion failed.

This is coming from the assertion.

At the end, we have an assertion.

Why does the assertion above it failed.

Nobody will believe his assertion that he is innocent.

So we've seen the list of callers, the location of the assertion of the program, and the failing assertion itself.

What you do instead is you put the functionality into code that is outside of the assertion and then use the assertion only for checking the result.

It is important to note that his assertion is groundless.

So now here we have the correct assertion.

There is location that tell you where the assertion failed that is where in the code.

And we start with the assertion that, again, testing the entire input should fail.

Here as well, a simple assertion would have sufficed to catch the error, mainly an assertion that checks for the non existence of HTML tags in the output.

The assertion has failed, and the assertion fails precisely on our buggy input, double quote followed by a less than sign.

Do you feel the boredom contained in this assertion?

That is, the opening tag was probably stripped, and of course, the assertion didn't fire.

The question is whether Pex can now find an input that makes the assertion fail.

Generally speaking, if anything in your assertion has side effects such as this one, don't put it into the assertion.

Second, we raise an assertion exception. We knew that the program will immediately abort.

Certainly you have made an abominable assertion

Since the markup characters are being added, the assertion finally fails.

You will get the precise assertion that failed and you won't implant any time bombs

This is the input which should cause the assertion to fail, press and run, and as you can see down here, the assertion actually failed.

That's the whole point of debugging, trying to find the defect that causes an assertion to fail.

If your program fails with an assertion, you know that there's an error.

If the condition is false, then we raise an assertion error.

Indeed, with this fix applied, the assertion can no longer fail.

The location of the assertion in the program. In our case, line 1.

The contents of a lookbehind assertion are restricted such that all the strings it matches must have a fixedThe contents of a lookbehind assertion are restricted such that all the strings it matches must have a fixed length.

Well, explanation is an assertion about what's there, unseen, that accounts for what's seen.

Let's go and think backwards how the assertion possibly could have failed.

Assertion also easily allowed you to put the blame on specific places.

Here's our program, the assertion included, with our input as before and if tag should be set somewhere during the execution of this program, then the assertion should fail.

The assertion has not failed and this shows that during the execution, tag has never been set to foo.

Now let's practice the art of deduction on this example simply from the observation that this final assertion has failed.

Pex has not found a single input which causes the assertion to fail.

Instead, only adding characters to out is being executed. The assertion, finally, passes.

Do you get the failing assertion condition. In our case, 2 2 5.

So first, the failing assertion is identified down here as coming directly from the code.

So which information does one get from a failing Python assertion.

Such a functionality of assertion is available in all programming languages.