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Questions tagged [assertion]

An assertion is a software construct where the developer states ("asserts") a condition that he believes will always be true. If the condition evaluates to false in some languages an exception is thrown, in others a message is printed, and in others the program ceases to operate.

An assertion is a software construct where the developer states ("asserts") a condition that he believes will always be true. If the condition evaluates to false, in some languages an exception is thrown, in others a message is printed, and in still others the program ceases to operate.

Assertions can exist in most high-level languages (C, Java, etc...) as well as in register-transfer-languages (RTL) such as Verilog, System Verilog, and VHDL.

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What is the use of "assert" in Python?

What does assert mean? How is it used?
Hossein
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What are assertions in Java and when should they be used?

What are some real life examples to understand the key role of the Java assert keyword?
Praveen
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Best practice for using assert?

Is there a performance or code maintenance issue with using assert as part of the standard code instead of using it just for debugging purposes? Is assert x >= 0, 'x is less than zero' better or worse than if x < 0: raise Exception('x is less…
meade
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How do I assert my exception message with JUnit Test annotation?

I have written a few JUnit tests with @Test annotation. If my test method throws a checked exception and if I want to assert the message along with the exception, is there a way to do so with JUnit @Test annotation? AFAIK, JUnit 4.7 doesn't provide…
Cshah
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How do I use Assert.Throws to assert the type of the exception?

How do I use Assert.Throws to assert the type of the exception and the actual message wording? Something like this: Assert.Throws( ()=>user.MakeUserActive()).WithMessage("Actual exception message") The method I am testing throws…
epitka
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When should I use Debug.Assert()?

I've been a professional software engineer for about a year now, having graduated with a CS degree. I've known about assertions for a while in C++ and C, but had no idea they existed in C# and .NET at all until recently. Our production code contains…
Nicholas Mancuso
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What does the "assert" keyword do?

What does assert do? For example in the function: private static int charAt(String s, int d) { assert d >= 0 && d <= s.length(); if (d == s.length()) return -1; return s.charAt(d); }
Peiska
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When to use an assertion and when to use an exception

Most of the time I will use an exception to check for a condition in my code, I wonder when it is an appropriate time to use an assertion? For instance, Group group=null; try{ group = service().getGroup("abc"); }catch(Exception e){ //I dont…
cometta
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Why do I get a C malloc assertion failure?

I am implementing a divide and conquer polynomial algorithm so I can benchmark it against an OpenCL implementation, but I can't get malloc to work. When I run the program, it allocates a bunch of stuff, checks some things, then sends the size/2 to…
Chris
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What is the expected syntax for checking exception messages in MiniTest's assert_raises/must_raise?

What is the expected syntax for checking exception messages in MiniTest's assert_raises/must_raise? I'm trying to make an assertion something like the following, where "Foo" is the expected error message: proc { bar.do_it }.must_raise…
kfitzpatrick
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Debug.Assert vs Exception Throwing

I've read plenty of articles (and a couple of other similar questions that were posted on StackOverflow) about how and when to use assertions, and I understood them well. But still, I don't understand what kind of motivation should drive me to use…
unknown
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AssertEquals 2 Lists ignore order

That should be really simple question I believe. But somehow I can't find answer in Google. Assume that I have 2 Lists of Strings. First contains "String A" and "String B", second one contains "String B" and "String A" (notice difference in order).…
kukis
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CollectionAssert in jUnit?

Is there a jUnit parallel to NUnit's CollectionAssert?
ripper234
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How to assert that an iterable is not empty on Unittest?

After submitting queries to a service, I get a dictionary or a list back and I want to make sure it's not empty. I using Python 2.7. I am surprised of not having any assertEmpty method for the unittest.TestCase class instance. The existing…
Alex Tereshenkov
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PHPUnit: assertInstanceOf() not working when passing type as second argument as non-string

I need to check if a variable is an object of the User type. User is my class $user my object $this->assertInstanceOf($user, User); This is not working. I have a use of undefined constant User - assumed 'User'.
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