Translate _ as __

[AndrewGaspar]

This change treats _ as a reserved identifier to resolve the bug reported in #631.

I have one concern - if the header has both an _ and __ identifier in the global namespace, this will cause a conflict. However, it seems like we already don't handle that case for keyword_ (e.g. abstract_, alignof_, etc.) so it doesn't seem like we need a solution specifically for __ in this change.

Fixes #631.

[highfive]

Warning

• These commits modify unsafe code. Please review it carefully!

[fitzgen]

👍 thanks @AndrewGaspar !

[fitzgen]

👍 thanks @AndrewGaspar !

[fitzgen]

I have one concern - if the header has both an _ and __ identifier in the global namespace, this will cause a conflict. However, it seems like we already don't handle that case for keyword_ (e.g. abstract_, alignof_, etc.) so it doesn't seem like we need a solution specifically for __ in this change.

We attempt to handle this sort of thing during the codegen phase, and have a map of method names and field names where we count how many times a name has been seen, and append that number to the name for disambiguation. So you get foo, foo1, foo2, foo3. etc.

It isn't perfect, but... shrug

[fitzgen]

@bors-servo r+

[bors-servo]

📌 Commit aa11524 has been approved by fitzgen

[bors-servo]

⌛️ Testing commit aa11524 with merge 5b49548...

[bors-servo]

☀️ Test successful - status-travis
Approved by: fitzgen
Pushing 5b49548 to master...