Queries starting and ending with a nested query create infinite loop. (a AND b) OR (x AND y)

[riichard]

This is because removeOuterBrackets() doesn't recognise that these are outer brackets. Making the split-root function parse the string as follows.

(a AND b) OR (x AND y)

Which after removeOuterBrackets() becomes:

a AND b) OR (x AND y

Which then becomes this with the splitRoot('AND', str) function:

1. a
2. b) OR (x
3. y

The removeOuterBrackets() part creates an issue. Best is to bring some intelligence to there.