Thanks Sven.
cheers -ben
On Tue, Mar 7, 2017 at 2:43 AM, Sven Van Caekenberghe <s...@stfx.eu> wrote:
> Ben,
>
> I tried to avoid #isString and #isSymbol and I thought it was clear that
> #assert:equals: used #= but I agree that I could be more explicit. Here is
> the changed version of the unit test (.2 of slice):
>
> testConcatenationIsSymbol
> "Concatenating 2 symbols results in another symbol"
> self assert: (#foo , #bar) isSymbol.
> self assert: (#foo , #bar) == #foobar.
>
> "Concatenating the empty Symbol does not change a Symbol"
> self assert: (#foo , emptySymbol) == #foo.
> self assert: (emptySymbol , #foo) == #foo.
>
> "Strings and Symbols can still be mixed, the receiver determines the
> result type"
> "Symbol receiver gives Symbol result"
> self assert: (#foo , 'bar') isSymbol.
> self assert: (#foo , 'bar') == #foobar.
> "String receiver gives String result"
> self assert: ('foo' , #bar) isString.
> self assert: ('foo' , #bar) = 'foobar'.
> "Strings and Symbols still compare content-wise"
> self assert: ('foo' , #bar) = #foobar.
> "But Strings and Symbols are not identical"
> self deny: ('foo' , #bar) == #foobar.
>
>
>> On 6 Mar 2017, at 15:18, Ben Coman <b...@openinworld.com> wrote:
>>
>> On Mon, Mar 6, 2017 at 9:21 PM, Sven Van Caekenberghe <s...@stfx.eu> wrote:
>>>
>>>> On 6 Mar 2017, at 14:12, Ben Coman <b...@openinworld.com> wrote:
>>>>
>>>>
>>>>
>>>> On Mon, Mar 6, 2017 at 5:54 PM, Sven Van Caekenberghe <s...@stfx.eu> wrote:
>>>> Here is a concrete proposal:
>>>>
>>>> https://pharo.fogbugz.com/f/cases/19802/Make-sure-Symbol-concatenation-results-in-a-Symbol-not-a-String
>>>>
>>>> This gives the following assertions:
>>>>
>>>> "Concatenating 2 symbols results in abother symbol"
>>>> self assert: (#foo , #bar) == #foobar.
>>>>
>>>> "Concatenating the empty symbol does not change a symbol"
>>>> self assert: (#foo, emptySymbol) == #foo.
>>>> self assert: (emptySymbol, #foo) == #foo.
>>>>
>>>> "Strings and symbols can still be mixed, the receiver determines
>>>> the result type"
>>>> "Symbol receiver gives symbol result"
>>>> self assert: (#foo , 'bar') == #foobar.
>>>> "String receiver gives string result"
>>>> self deny: ('foo' , #bar) == #foobar.
>>>> self assert: ('foo' , #bar) equals: #foobar.
>>>> self assert: ('foo' , #bar) equals: 'foobar'.
>>>>
>>>>
>>>> Those last two seem contradictory.
>>>
>>> No, Symbols and String can be used interchangeably in Pharo in lots of
>>> contexts. Particularly when comparing them, it makes no difference, all the
>>> following are/have always been true, independent of this change:
>>>
>>> #foo = 'foo'
>>> 'foo' = #foo
>>> #foo = #foo
>>> 'foo' = 'foo'
>>
>> Ah-ha... gotchya. always something more to learn.
>>
>> So those last three lines a testing that it is a String?
>> This meaning is pretty well hidden in the implicit behaviour.
>> Why not just...
>> self assert: (#foo , 'bar') isString
>> which seems to better "says what it means"
>>
>> If such is poor form in general,
>> I'm curious to what degree such rules may be relaxed for unit tests.
>> Could it be considered something like premature optimisation
>> to make the test too generic?? If isString latter causes a problem later,
>> deal with it then.
>>
>> ====
>> On another slightly different point,
>> this might be one case where #assert:#equals is less clear than using "="
>>
>> Its also easy to mis-think the following is contradictory
>>>> self deny: ('foo' , #bar) == #foobar.
>>>> self assert: ('foo' , #bar) equals: #foobar.
>>
>> where the alternative here makes the distinction more clear...
>> self deny: ('foo' , #bar) == #foobar.
>> self assert: ('foo' , #bar) = #foobar.
>>
>>
>> cheers -ben
>
>
