RFR(S): 8165433: Convert Test_linked_list to Gtest

[Kirill Zhaldbybin]

David,

Thank you for review!

Regards, Kirill

On 09/09/2016 08:03 AM, David Holmes wrote:
> On 8/09/2016 10:32 PM, Kirill Zhaldybin wrote:
>> Igor,
>>
>> Thank you for clarifying this!
>
> Indeed! Thank you very much.
>
>> David,
>>
>> Here are a new WebRev:
>> http://cr.openjdk.java.net/~kzhaldyb/webrevs/JDK-8165433/webrev.03/
>>
>> I changed asserts like ASSERT_NE(i, (Integer*) NULL) to ASSERT_TRUE,
>> changed order in ASSERT_EQ with NULL, changed order in ASSERT_EQ to make
>> expected value first parameter.
>>
>> Could you please let me know your opinion?
>
> Looks terrific! :)
>
> Thanks,
> David
>
>> Thank you.
>>
>> Regards, Kirill
>>
>> On 08.09.2016 12:22, Igor Ignatyev wrote:
>>> David,
>>>
>>> I ain’t Kim, but if you don’t mind I’d like to say what I see as the
>>> best way to handle that is and why.
>>>
>>> as Kirill said gtest’s asserts are strict about types and one will get
>>> compile time error trying to compare different types, long and pointer
>>> in this case (as the matter of fact, you can not compare pointers to
>>> different types either). however gtest supports comparison w/ NULL,
>>> but only in ASSERT/EXPECT_EQ and only if NULL is the 1st argument[1].
>>> so you can easily write ASSERT_EQ(NULL, i), but you can not write
>>> ASSERT_NE(NULL, i), you have to write ASSERT_NE(i != NULL) instead,
>>> [2] is the explanation from gtest faq why it so, in two words: in case
>>> ASSERT_NE(i, NULL) fails, you do know the value of i so ASSERT_TRUE(i
>>> != NULL) won’t lose any information.
>>>
>>> summing up, Kirill’s code can be changed like that:
>>>> diff -r 28f34e9482b4 test/native/utilities/test_linkedlist.cpp
>>>>     Integer* i = ll.find(six);
>>>> -  ASSERT_NE(i, (Integer*) NULL) << "Should find it";
>>>> +  ASSERT_TRUE(i != NULL) << "Should find it";
>>>>     ASSERT_EQ(i->value(), six.value()) << "Should be 6";
>>>>       i = ll.find(three);
>>>> -  ASSERT_EQ(i, (Integer*) NULL) << "Not in the list";
>>>> +  ASSERT_EQ(NULL, i) << "Not in the list";
>>> as you can see, there is no casting.
>>>
>>> could you please let me know what you think about the proposed way?
>>>
>>> [1] actually, the 1st argument in ASSERT/EXPECT_EQ is assumed to be an
>>> expected value, so you should write ASSERT_EQ(5, a) not ASSERT_EQ(a, 5)
>>> [2]
>>> https://github.com/google/googletest/blob/master/googletest/docs/V1_7_FAQ.md#why-does-google-test-support-expect_eqnull-ptr-and-assert_eqnull-ptr-but-not-expect_nenull-ptr-and-assert_nenull-ptr 
>>>
>>>
>>>
>>> Thanks,
>>> — Igor
>>>
>>>> On Sep 8, 2016, at 10:18 AM, David Holmes <david.holmes at oracle.com>
>>>> wrote:
>>>>
>>>>>> You should not have to cast NULL:
>>>>>>
>>>>>> 77   ASSERT_EQ(i, (Integer*) NULL) << "Not in the list";
>>>>>>
>>>>>> why is this needed? Is this something broken in gtest ??
>>>>> There is no ASSERT_NULL (we likely should add it) in GTest so 
>>>>> ASSERT_EQ
>>>>> is used.
>>>>> ASSERT_EQ is pretty strict about types so since NULL resolves to long
>>>>> int (at least on my host) it cannot be compared with Integer*.
>>>> I'm unhappy about this, it is a deficiency in Gtest. We should not be
>>>> casting  0 or NULL to specific pointer types.
>>>>
>>>> cc'ing Kim to get his opinion on the best way to handle this.
>>