EVOLUTION-MANAGER

Edit File: qcolumns.py

# Copyright 2012 Matt Chaput. All rights reserved.
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from whoosh.matching import ConstantScoreMatcher, NullMatcher, ReadTooFar
from whoosh.query import Query

class ColumnQuery(Query):
    """A query that matches per-document values stored in a column rather than
    terms in the inverted index.

This may be useful in special circumstances, but note that this is MUCH
    SLOWER than searching an indexed field.
    """

def __init__(self, fieldname, condition):
        """
        :param fieldname: the name of the field to look in. If the field does
            not have a column, this query will not match anything.
        :param condition: if this is a callable, it is called on each value
            in the column, and for documents where callable(docvalue) returns
            True are returned as matching documents. If this is not a callable,
            the document values are compared to it (using ``==``).
        """

self.fieldname = fieldname
        self.condition = condition

def is_leaf(self):
        return True

def matcher(self, searcher, context=None):
        fieldname = self.fieldname
        condition = self.condition
        if callable(condition):
            comp = condition
        else:
            def comp(v):
                # Made this a function instead of a lambda so I could put
                # debug prints here if necessary ;)
                return v == condition

reader = searcher.reader()
        if not reader.has_column(fieldname):
            return NullMatcher()

creader = reader.column_reader(fieldname)
        return ColumnMatcher(creader, comp)

class ColumnMatcher(ConstantScoreMatcher):
    def __init__(self, creader, condition):
        self.creader = creader
        self.condition = condition
        self._i = 0
        self._find_next()

def _find_next(self):
        condition = self.condition
        creader = self.creader

while self._i < len(creader) and not condition(creader[self._i]):
            self._i += 1

def is_active(self):
        return self._i < len(self.creader)

def next(self):
        if not self.is_active():
            raise ReadTooFar
        self._i += 1
        self._find_next()

def reset(self):
        self._i = 0
        self._find_next()

def id(self):
        return self._i

def all_ids(self):
        condition = self.condition
        for docnum, v in enumerate(self.creader):
            if condition(v):
                yield docnum

def supports(self, astype):
        return False

def skip_to_quality(self, minquality):
        if self._score <= minquality:
            self._i = len(self.creader)
            return True