Warn compile_error only when input is finished

Let's say we are in progress to write `"foo"`:

```
irb> "fo
```

at this moment, nothing is wrong.
It would be just a normal way to write `"foo"`.

Prior to this commit, the `fo` part was warned because of
5b64d7ac6e7cbf759b859428f125539e58bac0bd. But I think warning such a
normal input is not valuable for users.

However, we'd like to warn `:@1` or `@@1` which is also a syntax error.
Then this commit switches the syntax highlight based on whether the
input text is finished or not. When it's not finished yet, it does not
warn compile_error.

0 files changed, 0 insertions, 0 deletions