Inconsistent (unexpected) matching behavior with One:Many referenced object / scalar

[jackdpeterson]

        $applicableParts = $partCollection->matching(
            Criteria::create()->where(Criteria::expr()->eq('partStatusType', \PartStatusType::Qualified))
        );

The above doesn't work. Below does.

$applicableParts = $partCollection->matching(
            Criteria::create()->where(Criteria::expr()->in('partStatusType', [\PartStatusType::Qualified]))
        );

This seems like odd behavior. Perhaps some documentation would be helpful because on first pass it seems like that one would be able to use the eq() expression with a referenced object. However, that throws the

    {
        return new self(sprintf(
            "Cannot match on %s::%s with a non-object value. Matching objects by id is " .
            "not compatible with matching on an in-memory collection, which compares objects by reference.",
            $class, $associationName
        ));
    }

After playing around with this, I tried out the ->in() expression which seemed to work. Any reason why all matchers couldn't be updated to support the id of the entity itself?

[lcobucci]

@jackdpeterson could you please send us a failing test case that reproduces that behaviour? It would help us a lot to identify and fix the issue you're describing.

These tests can be used as example:

collections/tests/Doctrine/Tests/Common/Collections/CollectionTest.php

Lines 22 to 64 in 42c4039

	/**
	* @group DDC-1637
	*/
	public function testMatching() : void
	{
	$this->fillMatchingFixture();
	$col = $this->collection->matching(new Criteria(Criteria::expr()->eq('foo', 'bar')));
	self::assertInstanceOf(Collection::class, $col);
	self::assertNotSame($col, $this->collection);
	self::assertEquals(1, count($col));
	}
	/**
	* @group DDC-1637
	*/
	public function testMatchingOrdering() : void
	{
	$this->fillMatchingFixture();
	$col = $this->collection->matching(new Criteria(null, ['foo' => 'DESC']));
	self::assertInstanceOf(Collection::class, $col);
	self::assertNotSame($col, $this->collection);
	self::assertEquals(2, count($col));
	self::assertEquals('baz', $col->first()->foo);
	self::assertEquals('bar', $col->last()->foo);
	}
	/**
	* @group DDC-1637
	*/
	public function testMatchingSlice() : void
	{
	$this->fillMatchingFixture();
	$col = $this->collection->matching(new Criteria(null, null, 1, 1));
	self::assertInstanceOf(Collection::class, $col);
	self::assertNotSame($col, $this->collection);
	self::assertEquals(1, count($col));
	self::assertEquals('baz', $col[0]->foo);
	}