Unable to filter by eq(`\\`) in jsapi

[dsmmcken]

Description

I have a table that looks like this, with a table that outputs a row with just a \ in it.

from deephaven import new_table
from deephaven.column import string_col
testslash = new_table([
    string_col("test", ["\\", None, "null", "empty", "\\null"])
])

This jsapi filter does not match:
column.filter().eq(dh.FilterValue.ofString('\\'))

This filter does match:
column.filter().eqIgnoreCase(dh.FilterValue.ofString('\\'))

Expected results

eq should match

Actual results

eq does not match, but eqIgnoreCase does?

Additional details and attachments

You can reproduce from the UI instead of writing a raw jsapi calls if you want by right clicking the row, and select filter by value -> "text is equal", it will do the .eq (pay no attention to the =\ outputted in the quick filter box that part is wrong, but underneath it is doing \\)

Versions
Engine Version: 0.25.0
Web UI Version: 0.40.3
Java Version: 17.0.7
Barrage Version: 0.5.0

[niloc132]

There are at least two bugs here:

• a simple == filter between a column and a string literal should be normalized to a match filter in grpc
• escaping is being handled wrong between grpc and the engine's filter parser, so that the \ is being left unescaped as \