Collections equality test

Level 25

Hi @sr57

Maybe you could combine diff() and isEmpty() methods like this:

$col1->diff($col2)->isEmpty();

ref: https://laravel.com/docs/8.x/collections#method-diff

ref2: https://laravel.com/docs/8.x/collections#method-isempty

Hope this helps!

Best Answer

Level 75

$col1 = collect(['a','a','2','3']);

$col2 = collect(['a','a','2','3']);

$col1 == $col2; // true

$col1 = collect(['a','a','2','3']);

$col2 = collect(['a','2','3','3']);

$col1 == $col2; // false

So just

if ($col1 != $col2) {
    // they are different
}

Level 39

Thanks @michaloravec

I already tested with == that does not work , I forgot === & != ... !

Level 39

Hi @marianomoreyra

I have already tested, it does not work

if ( $col1->diff($col2)->isEmpty() ) echo "Ok"; else echo "KO";

// Ok

MarianoMoreyra

Level 25

You're right @sr57 , in this case that the elements are repeated, it doesn't work!

Anyway, I forgot that Collections are easier to compare, just like @michaloravec pointed out!!

Level 39

Thanks @marianomoreyra I fogot also to test with === and not with ==

@michaloravec @marianomoreyra

Level 39

Bets answer still to be found.

Sorry but we concluded too quicky.

$col1=collect('a','a','2','3');
$col2=collect('a','a','2','3');
echo "Ok expected : ";
if ( $col1 === $col2 ) echo "Ok"; else echo "KO";
if ( $col1 !== $col2 ) echo "KO"; else echo "Ok";
if ( $col1 != $col2 ) echo "KO"; else echo "Ok";
if ( $col1 == $col2 ) echo "Ok"; else echo "KO";

// Ok expected : KOKOOkOk


$col1=collect('a','a','2','3');
$col2=collect('a','2','3','3');
echo "<br>KO expected : ";
if ( $col1 === $col2 ) echo "Ok"; else echo "KO";
if ( $col1 !== $col2 ) echo "KO"; else echo "Ok";
if ( $col1 != $col2 ) echo "KO"; else echo "Ok";
if ( $col1 == $col2 ) echo "Ok"; else echo "KO";

// KO expected : KOKOOkOk

https://www.php.net/manual/en/language.oop5.object-comparison.php

Level 75

@sr57 === and !== don't work. You have to use only == or !=.

This create collection which contain only letter a.

collect('a','a','2','3');

You need to use square brackets.

collect(['a','a','2','3']);

By the way I gave you a correct answer.

A collection is instance of Illuminate\Support\Collection so it's a classic class and here is an explaination why you can't use a strict compare operators.

1 like

Level 39

@michaloravec

You have to use only == or !=

does not work in the second example*

need to use square brackets

In 'real life' collections come from calculations and are more much more complex than this simple example.

*It's late, hope I'am not wrong ... to be continued tomorrow (for me)

Level 75

@sr57 I don't know what you want to think about.

MarianoMoreyra

Level 25

@sr57

In 'real life' collections come from calculations and are more much more complex than this simple example

True, but also they come well formed as opposed to your example, as @michaloravec explained.

If you were to compare 2 collections, returned from a calculation or even a query from DB, using == or != should work.

Try that tomorrow with a fresh mind so you can be sure that @michaloravec reply is the best answer.

Have a nice sleep!

Level 39

Good morning @michaloravec and @marianomoreyra

After a good night, I confirm that both of you are right ... but I'm not wrong

The collect method returns a new Collection instance

See below, my first example is not Ok, of course it should not be a "well formed" collection, but as written before, it's a Collection instance, I miss probably st.

function aff($test,$exp,$res) {
	echo "$test";
	if ( $exp == $res ) echo " Ok , "; else echo " KO , ";
}

function test($exp,$col1,$col2) {
	# exp : 1 col1=col2, 0 col1!=col2
	echo "<br>test : $col1 $col2 : ";
#	if ( $col1 === $col2 ) $res=1; else $res=0;aff("===",$exp,$res);
#	if ( $col1 !== $col2 ) $res=0; else $res=1;aff("!==",$exp,$res);
	if ( $col1 != $col2 ) $res=0; else $res=1;aff("!=",$exp,$res);
	if ( $col1 == $col2 ) $res=1; else $res=0;aff("==",$exp,$res);
}

$col1=collect('a','a','2','3');
$col2=collect('a','a','2','3');
test(1,$col1,$col2);
$col2=collect('a','2','3','3');
test(0,$col1,$col2);
echo "<br>";

// test : ["a"] ["a"] : != Ok , == Ok ,
// test : ["a"] ["a"] : != KO , == KO ,

$col1=collect(['a','a','2','3']);
$col2=collect(['a','a','2','3']);
test(1,$col1,$col2);
$col2=collect(['a','2','3','3']);
test(0,$col1,$col2);
echo "<br>";

// test : ["a","a","2","3"] ["a","a","2","3"] : != Ok , == Ok ,
// test : ["a","a","2","3"] ["a","2","3","3"] : != Ok , == Ok ,

Level 75

@sr57 I don't know why are you focusing on your first example. How I said you have to pass an array there..,

Level 39

Hi @michaloravec

As I wrote before, in 'real life' I should have somewhere in my code a not 'well formed collection' and your solution is not obvious.

I like Laravel, but clearly I don't like such situation ... to be continued.

Maybe we can link with this post https://laracasts.com/discuss/channels/laravel/laravel-sanitary-check

Level 75

@sr57 What does it mean not well formed collection?

And why my solution is not obvious?

Level 39

Collections that seem equal but don' pass the test == like the ones in the previous example.

Since I haven't find the "pb" in my code I have no other example.

Level 75

@sr57 Oh my God.

This is not collection!

collect('a','a','2','3');

Level 39

From the doc, collect returns a collection and I got no error with this syntax ... so it's a collection or I miss st

Level 75

@sr57 collect() accept only one parameter.

collect('a', 'a', '2', '3')->toArray(); // ['a']

So you need to pass it as an array

collect(['a', 'a', '2', '3'])->toArray(); // ['a', 'a', '2', '3']

When you told that the first example didn't work, it doesn't matter because you don't create a collection.

Level 39

@michaloravec

That's clear

Both examples you gave return collections, but the first one doesn't pass the test '==' , see previous post.

Level 75

@sr57 What else can I say....

$col1 = collect('a', 'a', '2', '3');

$col2 = collect('a', '2', '3', '3');

$col1 == $col2 // true

And it's correct because

$col1 = collect('a', 'a', '2', '3'); // this is same as collect(['a']);

$col2 = collect('a', '2', '3', '3'); // this is same as collect(['a']);

So what I said is correct.

Level 75

@sr57 No response?