Add tests for partition

[dgr]

Closes #389

[Copilot]

Pull request overview

Adds a new clojure.core/partition test namespace to cover expected behavior across its supported arities and validate laziness characteristics (issue #389).

Changes:

• Introduces a new partition.cljc test file guarded by (when-var-exists partition ...).
• Adds assertions for arities 2/3/4 including overlapping partitions, padding behavior, and empty/nil collection inputs.
• Includes checks that the result is a lazy seq and initially unrealized.

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[jeaye]

Nice work!

[jeaye]

Potential test: What if pad collection is too small?

Potential test: What if pad collection is empty?

[dgr]

Yes, added.

[dgr]

I believe this is ready to merge.

[jeaye]

I'm not convinced we want the TODO for the floating point value support, since I gather that the fn is intended to only accept integral values. CLJS just happens to support it since there's only one number type for JS.

I think we should remove the floating point case, and the TODO. Keeping the big integer case is good, though, since it's an integral type.

[E-A-Griffin]

I'm not convinced we want the TODO for the floating point value support, since I gather that the fn is intended to only accept integral values. CLJS just happens to support it since there's only one number type for JS.

I think we should remove the floating point case, and the TODO. Keeping the big integer case is good, though, since it's an integral type.

I think the test is good to keep but the TODO should be dropped as I don't think non CLJS are obligated to do any particular behavior with floats, that being said, I think CLJS' behavior is interesting and worth documenting here (could see this causing a real bug in the wild for someone)

[E-A-Griffin]

I think we should add a test for (partition 0 ...) akin to what's shown here: https://clojuredocs.org/clojure.core/partition#example-57aa75fae4b0bafd3e2a04d3

[E-A-Griffin]

Mostly looks good, left some optional suggestions

[dgr]

I think we should add a test for (partition 0 ...) akin to what's shown here: https://clojuredocs.org/clojure.core/partition#example-57aa75fae4b0bafd3e2a04d3

Sorry for the lag. Been busy with other things.

I originally tried some tests like that with zero and negative values for n and step, but they hang or repeat infinite values, which made me rethink them. Yes, the example at clojuredocs.org uses take to get the first few of an infinite stream of empty lists. But is that really useful? Is that really within the contract that partition is making? The assumption seems to be that n and step are positive integers, not zero or negative.