Convert `ArrayMap` to `collections.abc`

[nedtwigg]

Selfie has a few generic data structures that we use in lots of places. In order of complexity, they are:

selfie-python-wip/jvm/selfie-lib/src/commonMain/kotlin/com/diffplug/selfie/ArrayMap.kt

Line 39 in c41e68c

abstract class ListBackedSet<T>() : AbstractSet<T>() {

selfie-python-wip/jvm/selfie-lib/src/commonMain/kotlin/com/diffplug/selfie/ArrayMap.kt

Lines 248 to 252 in c41e68c

	/**
	* An immutable, sorted, array-backed set - if keys are [String], they have a special sort order
	* where `/` is the lowest key.
	*/
	class ArraySet<K : Comparable<K>>(private val data: Array<Any>) : ListBackedSet<K>() {

selfie-python-wip/jvm/selfie-lib/src/commonMain/kotlin/com/diffplug/selfie/ArrayMap.kt

Lines 65 to 69 in c41e68c

	/**
	* An immutable, sorted, array-backed map - if keys are [String], they have a special sort order
	* where `/` is the lowest key.
	*/
	class ArrayMap<K : Comparable<K>, V : Any>(private val data: Array<Any>) : Map<K, V> {

We should implement them in Python using the collections.abc framework.

• ListBackedSet should extend Set and Sequence
• ArrayMap should extend Mapping

We have a few tests for these here, but there should be more.

https://github.com/diffplug/selfie-python-wip/blob/main/jvm/selfie-lib/src/commonTest/kotlin/com/diffplug/selfie/ArrayMapTest.kt

I think using PEP 695 will make the rest of this easier, but it's not a hard requirement.

Here's an example conversation with ChatGPT for going about this task.

[nedtwigg]

• Make sure to look at Type hints & ChatGPT #16

[nedtwigg]

• Mostly completed by ArrayMap.py #17
• Remaining issues for the medium-term future
  • special sort order for strings
  • use binary search, never linear search

[nedtwigg]

• Being addressed in Update ArrayMap #50