On 12 avr. 2011, at 23:47, Werner Kassens wrote:
hi, i have a testsuite that is a subclass of TestCase with this method:
testStupid |a| a :=#(1). self assert: a first isNumber . a :=a at:1 put: nil.
if i run the test once, it succeeds, but but when i run it a second time it fails. this seems to be sligthly counterintuitive, or how do i have to understand it?
Interesting, I would never have guessed the test would be broken at first sight. So maybe some people enlightened in the ways of the compiler can provide a better explanation than me. Here is my guess: #(1) is a special construct which creates a compile-time array. The compile-time makes the trick: in short the array is more or less encoded directly into the bytecodes of the method as a constant. But modifying the array with #at:put: directly modifies the bytecodes in the compiled method itself. So you create a side-effect directly into your method. Am I the only one to find this a bit dangerous and not intuitive? Is it a well-known behavior? A correct way to fix that would be to use a dynamic array {1} or define a setUp method which would initialize the array before each run. -- Simon Denier