[furcas-discussion] Zweimal dieselbe Sprache

[Uhl, Axel]

Hi Sebastian,

it seems the problem you were having with the two tests failing when executed in a suite instead of separately is related to you using the same language definition with the same name in two subsequent distinct test cases. I copied NestedScopes.tcs to NestedScopes2.tcs and renamed the language defined inside, then adjusted the second test case that previously used NestedScopes.tcs, too. Now all tests are green for me locally.

I suppose the following happened: when parsing the language definition, a transient resource containing the mapping definition was created. The parser generated produced a parser class which got compiled. The package/name for this class is derived from the language name. When the second test case is run, the same language definition is used again to produce another mapping / parser combination. I assume the mapping ended up in a new transient resource as another copy. The parser may have gotten written again to the generationTemp folder, overwriting the previously generated parser / lexer files. And even though the compiler may have produced a new copy of the .class files, I don't assume the class loader would have loaded those new copies again because it still had the old copy loaded.

This would even have been OK from a language / parsing perspective since the language definition hasn't changed in between. However, since the parser contains the URIs of the mapping elements and the mapping was re-created / re-loaded with a new transient resource, parser and mapping are out of sync, and the parser now can't find the mapping elements anymore. This also explains why it works if the failing test is executed in isolation.

I pushed the change to github and hope this will "blueify" the master. We should probably keep this in mind when constructing test cases in the future. If you find a good, robust way to re-use the same language definition, e.g., by trying to use a separate class loader for loading the parser and lexer class, then that's fine, too.

Best,
-- Axel