Bug: Detecting lambda expressions for nested compiler generated classes about jsil

[kg]

Can you provide a simple test case?

[matra774]

Here is a sammpe.

static void TestNestedLambda()
{
  var set1 = new int[] { 1, 2, 3 };
  var set2 = new int[] { 2, 3, 5 };

  var intersection = set1.Where(x => set2.Any(y => y == x)); 

}

The problem occurrs if you have nested lambda expressions (i.e. the innse lambda expresion references the variable from the outer one).

If you add the folowing block after the assigment to emitInLine:

if (methodMember.Method.IsIgnored && !emitInline) // matra774 https://github.com/kevingadd/JSIL/issues/37
{
  Console.WriteLine("WARNING: {0} is ignored, but is not considered to be emmited inline. ", methodDot);
}

You will get the following warning when runing JSILC:

WARNING: <JSType 'TestHelloWorld.Program/<>c__DisplayClass2/<>c__DisplayClass4'>.<JSStringIdentifier 'prototype'>.<JSMethod '<TestNestedLambda>b__1'> is ignored, but is not considered to be emmited inline. 

Here are some other sasamples from Mono's implementation of LINQ:

WARNING: <JSType 'System.Linq.Enumerable'>.<JSMethod '<ToLookup>b__bb`2'> is ignored, but is not considered to be emmited inline. 

WARNING: <JSType 'System.Linq.Enumerable/PredicateOf`1<T>'>.<JSMethod 'cctor>b__c9'> is ignored, but is not considered to be emmited inline. 

WARNING: <JSType 'System.Linq.Enumerable/Function`1<T>'>.<JSMethod 'cctor>b__cb'> is ignored, but is not considered to be emmitd inline. 

[kg]

All the issues demonstrated by your test case should be fixed in bf107bc.

[markusjohnsson]

I'm not positive it is fixed though as I'm seeing a related error.

Will continue to debug and hopefully provide another test case (oh, and a fix if I can figure it out)

[markusjohnsson]

Didn't come up with a test for this.. but what happened for me was that I had a method with identifier "<System.Collections.ICollection.CopyTo>b__0" (from mono's Dictionary) which was ignored (it is a delegate), but "compilerGenerated" became false so it went straight to the exception.

I've tested to always emit inline if method is ignored and it works so far. I haven't ran the unit tests using this though because I'm in my corlib setup and the unit tests doesn't compile.. Might continue on sunday.

[kg]

Emitting if ignored sounds like a reasonable heuristic. I'll see if that breaks any tests.