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Questions tagged [assertions]

Assertion is a method of verifying, if the code works as it was designed to. For instance, after reading an XML file, the result should contain exactly one root node. Failed assertion means, that program is in an unstable state and usually in such case its execution is terminated.

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Cycles in family tree software

I am the developer of some family tree software (written in C++ and Qt). I had no problems until one of my customers mailed me a bug report. The problem is that the customer has two children with their own daughter, and, as a result, he can't use my…
Partick Höse
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Comparing arrays in JUnit assertions, concise built-in way?

Is there a concise, built-in way to do equals assertions on two like-typed arrays in JUnit? By default (at least in JUnit 4) it seems to do an instance compare on the array object itself. EG, doesn't work: int[] expectedResult = new int[] { 116800,…
mBria
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assertAll vs multiple assertions in JUnit5

Is there any reason to group multiple assertions: public void shouldTellIfPrime(){ Assertions.assertAll( () -> assertTrue(isPrime(2)), () -> assertFalse(isPrime(4)) ); } instead of doing this: public void…
Wilhelm Olejnik
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Does R have an assert statement as in python?

a statement that checks if something is true and if not prints a given error message and exits
Dan
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Eclipse: enable assertions

I'm running Eclipse Galileo. How do I enable assertions in Eclipse? As suggested by other sites, I've tried adding the arguments: -ea. I have also tried changing the compiler compliance level to 1.4. Neither of those suggestions worked.
well actually
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assert vs. JUnit Assertions

Today I saw a JUnit test case with a java assertion instead of the JUnit assertions—Are there significant advantages or disadvantages to prefer one over the other?
Robert
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How to change the message in a Python AssertionError?

I'm writing per the following, in which I try to produce a decent error message when comparing two multiline blocks of Unicode text. The interior method that does the comparison raises an assertion, but the default explanation is useless to me I…
Andres Jaan Tack
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Avoiding unused variables warnings when using assert() in a Release build

Sometimes a local variable is used for the sole purpose of checking it in an assert(), like so - int Result = Func(); assert( Result == 1 ); When compiling code in a Release build, assert()s are usually disabled, so this code may produce a warning…
Hexagon
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Why should I use asserts?

I never got the idea of asserts -- why should you ever use them? I mean, let's say I were a formula driver and all the asserts were things like security belt, helmet, etc. The tests (in debug) were all okay, but now we want to do racing (release)!…
jan
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How to enable the Java keyword assert in Eclipse program-wise?

How can I enable the assert keyword in Eclipse? public class A { public static void main(String ... args) { System.out.println(1); assert false; System.out.println(2); } }
Siva Kumar Reddy G
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How to implement XUnit descriptive Assert message?

Context in XUnit github I found this: Add Assert.Equal(expected, actual, message) overload #350 (so a developer ask for a non existing overload see below) Quote from the answer: We are a believer in self-documenting code; that includes your…
g.pickardou
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Java/ JUnit - AssertTrue vs AssertFalse

I'm pretty new to Java and am following the Eclipse Total Beginner's Tutorials. They are all very helpful, but in Lesson 12, he uses assertTrue for one test case and assertFalse for another. Here's the code: // Check the book out to p1 (Thomas) //…
Thomas
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C compiler asserts - how to implement?

I'd like to implement an "assert" that prevents compilation, rather than failing at runtime, in the error case. I currently have one defined like this, which works great, but which increases the size of the binaries. #define…
NickB
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Detecting whether on UI thread in WPF and Winforms

I've written an assertion method Ensure.CurrentlyOnUiThread(), below, that checks that the current thread is a UI thread. Is this going to be reliable in detecting the Winforms UI thread? Our app is mixed WPF and Winforms, how best to detect a…
chillitom
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How to catch an assert with Google test?

I'm programming some unit test with the Google test framework. But I want to check whether some asserts are well placed and are useful. Is there a way to catch an assert in Google test? Example code under test: int factorial(int n){ assert(n >=…
Killrazor
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