Enso numbers polyglot API inconsistency

[Akirathan]

While working on #11468, I revealed an inconsistency in how we respond to some polyglot messages: https://github.com/enso-org/enso/pull/11468/files#r1859020769

The issue is in the following newly added tests (all of which are passing on develop):

enso/engine/runtime-integration-tests/src/test/java/org/enso/interpreter/test/BigNumberTest.java

Lines 182 to 216 in 19328ac

	@Test
	public void everyValueSmallerThanIntegerMaxVal_IsPrimitiveInt() {
	var almostMaxInt = Integer.toString(Integer.MAX_VALUE - 1);
	var intVal = ContextUtils.evalModule(ctx, "main = " + almostMaxInt);
	assertThat("Is a number", intVal.isNumber(), is(true));
	assertThat("Fits in int", intVal.fitsInInt(), is(true));
	assertThat("Fits in long", intVal.fitsInLong(), is(true));
	assertThat("Fits in double", intVal.fitsInDouble(), is(true));
	assertThat("Fits in big int", intVal.fitsInBigInteger(), is(true));
	}
	@Test
	public void everyValueSmallerThanLongMaxVal_IsPrimitiveLong() {
	var almostMaxLong = Long.toString(Long.MAX_VALUE - 1);
	var longVal = ContextUtils.evalModule(ctx, "main = " + almostMaxLong);
	assertThat("Is a number", longVal.isNumber(), is(true));
	assertThat("Does not fit in int", longVal.fitsInInt(), is(false));
	assertThat("Fits in long", longVal.fitsInLong(), is(true));
	assertThat("Does not fit in double (but could)", longVal.fitsInDouble(), is(false));
	assertThat("Fits in big int", longVal.fitsInBigInteger(), is(true));
	}
	@Test
	public void everyValueBiggerThanLongMaxVal_IsEnsoBigInt() {
	// This number is bigger than Long.MAX_VALUE, but smaller than Double.MAX_VALUE
	// so it could technically fit in double, but in Enso, it is automatically converted
	// to EnsoBigInteger
	var bigIntVal = ContextUtils.evalModule(ctx, "main = 9223372036854775808");
	assertThat("Is a number", bigIntVal.isNumber(), is(true));
	assertThat("Does not fit in int", bigIntVal.fitsInInt(), is(false));
	assertThat("Does not fit in long", bigIntVal.fitsInLong(), is(false));
	assertThat("Does not fit in double (but could)", bigIntVal.fitsInDouble(), is(false));
	assertThat("Fits in big int", bigIntVal.fitsInBigInteger(), is(true));
	}

Revealed inconsistencies

According to Enso polyglot API:

• A long value fits in long, but does not fit in double.
• A value smaller than Double.MAX_VALUE and bigger than Long.MAX_VALUE does not fit in double, because it is automatically converted to EnsoBigInteger.

The aforementioned semantics work differently than host polyglot API. Long value should fit in long. A value smaller than Double.MAX_VALUE and bigger than Long.MAX_VALUE should fit in double. Am I right?

[Akirathan]

This inconsistency is blocking progress on #11468. We first need to resolve how the numbers should behave.

[Akirathan]

This is no inconsistency. I have just not correctly understood the definition of double and long. The tests will remain in the code base, and I have added comments in - 1826dde . Closing this issue.