Parser adds new line symbol to the source being parsed

[auduchinok]

[dsyme]

@auduchinok Could you give more context on why this is a problem

Context I know is

• New line is only added if the file doesn't already end in a new line
• This applies only to ParseAndCheckFileInProject and ParseFileInProject

But I don't know what specific problems it causes to add the new line character. Equally, I don't know why our tests are so sensitive to the character being there (beyond line number range reports - it's more dramatic than that I believe?)

Thanks!
don

[auduchinok]

@dsyme Adding a new line changes AST ranges which we rely on. We currently map these ranges to R# document offsets using approach very similar to the one used in RoslynHelpers.fs except getting min of lines count and a range line. It works fine when an empty line isn't added to the source and leads to ArgumentOutOfRangeException otherwise.

[dsyme]

@auduchinok OK thanks, that makes sense

[dsyme]

@auduchinok I'm labelling this a "Urgency Later" since we workaround it at the moment, but please feel free to submit a fix for it.

[auduchinok]

Fixed in #6001.