Adds a close() method to Compilation results

[axiak]

This close method will allow file manager to be closed. Otherwise, during a normal test running lots of compilations, the java process might accumulate file descriptors. These open files are generally not a problem, but in the latest MacOS Ventura, the limit of open file descriptors is set to a low number and impossible to increase.

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[cgdecker]

Is this an issue you've run into in practice with this? I haven't dug into the code much but it seems surprising to me that default file manager would hold open file descriptors given that FileObjects don't seem to represent open files and aren't Closeable themselves.

Either way, I'm not sure this is the approach I'd prefer to take, in part because it would break a lot of code using this that's checked to ensure that Closeable stuff is actually closed. I think ideally I'd want something where Compiler automatically uses and closes a single file manager for each test, which could be done by making it a TestRule (or making a TestRule wrapper for it) and/or giving Compiler a tear-down method that can be called in an @After method. These approaches would avoid the need to manually ensure that close() is called for each Compilation.

[cgdecker]

Actually I think it's a lot simpler than I thought at first. There isn't any need for the file manager to still be open once the compilation has finished, so we can just ensure it's closed in compile.