1278776 - Add a way to assert that we don't expand StreamingLexer's buffer unexpectedly

Status: NEW

(Core :: Graphics: ImageLib, defect, P3)

Description

[Seth Fowler [:seth] [:s2h]]

In general we should be setting StreamingLexer's size template parameter in such a way as to ensure that fixed-size states don't require expanding the buffer. It's also usually best practice to read variable-size state data in unbuffered mode. It'd be ideal to ensure that we're doing this by asserting that we never expand the buffer in StreamingLexer. If we do it there, we can identify the state that caused the problem.

What complicates this is that if we make this a hard policy, we can't use StreamingLexer to read in images row by row, which is incredibly convenient for some image formats. It's worth thinking about how to preserve this capability while still letting us detect when we *unexpectedly* expand the buffer.

Comment 1

[Nicholas Nethercote [inactive]]

> It's worth thinking about how to preserve this
> capability while still letting us detect when we *unexpectedly* expand the
> buffer.

Some kind of flag you can set to make the checking more lenient?