Improve issue search (#2387)

* Improve issue indexer

* Fix new issue sqlite bug

* Different test indexer paths for each db

* Add integration indexer paths to make clean

vendor/github.com/blevesearch/bleve/search/searcher/search_boolean.go

@@ -38,14 +38,14 @@ type BooleanSearcher struct {
 	initialized     bool
 }
 
-func NewBooleanSearcher(indexReader index.IndexReader, mustSearcher search.Searcher, shouldSearcher search.Searcher, mustNotSearcher search.Searcher, explain bool) (*BooleanSearcher, error) {
+func NewBooleanSearcher(indexReader index.IndexReader, mustSearcher search.Searcher, shouldSearcher search.Searcher, mustNotSearcher search.Searcher, options search.SearcherOptions) (*BooleanSearcher, error) {
 	// build our searcher
 	rv := BooleanSearcher{
 		indexReader:     indexReader,
 		mustSearcher:    mustSearcher,
 		shouldSearcher:  shouldSearcher,
 		mustNotSearcher: mustNotSearcher,
-		scorer:          scorer.NewConjunctionQueryScorer(explain),
+		scorer:          scorer.NewConjunctionQueryScorer(options),
 		matches:         make([]*search.DocumentMatch, 2),
 	}
 	rv.computeQueryNorm()

vendor/github.com/blevesearch/bleve/search/searcher/search_conjunction.go

@@ -31,10 +31,10 @@ type ConjunctionSearcher struct {
 	maxIDIdx    int
 	scorer      *scorer.ConjunctionQueryScorer
 	initialized bool
-	explain     bool
+	options     search.SearcherOptions
 }
 
-func NewConjunctionSearcher(indexReader index.IndexReader, qsearchers []search.Searcher, explain bool) (*ConjunctionSearcher, error) {
+func NewConjunctionSearcher(indexReader index.IndexReader, qsearchers []search.Searcher, options search.SearcherOptions) (*ConjunctionSearcher, error) {
 	// build the downstream searchers
 	searchers := make(OrderedSearcherList, len(qsearchers))
 	for i, searcher := range qsearchers {
@@ -45,10 +45,10 @@ func NewConjunctionSearcher(indexReader index.IndexReader, qsearchers []search.S
 	// build our searcher
 	rv := ConjunctionSearcher{
 		indexReader: indexReader,
-		explain:     explain,
+		options:     options,
 		searchers:   searchers,
 		currs:       make([]*search.DocumentMatch, len(searchers)),
-		scorer:      scorer.NewConjunctionQueryScorer(explain),
+		scorer:      scorer.NewConjunctionQueryScorer(options),
 	}
 	rv.computeQueryNorm()
 	return &rv, nil

vendor/github.com/blevesearch/bleve/search/searcher/search_disjunction.go

@@ -50,11 +50,22 @@ func tooManyClauses(count int) bool {
 }
 
 func tooManyClausesErr() error {
-	return fmt.Errorf("TooManyClauses[maxClauseCount is set to %d]", DisjunctionMaxClauseCount)
+	return fmt.Errorf("TooManyClauses[maxClauseCount is set to %d]",
+		DisjunctionMaxClauseCount)
 }
 
-func NewDisjunctionSearcher(indexReader index.IndexReader, qsearchers []search.Searcher, min float64, explain bool) (*DisjunctionSearcher, error) {
-	if tooManyClauses(len(qsearchers)) {
+func NewDisjunctionSearcher(indexReader index.IndexReader,
+	qsearchers []search.Searcher, min float64, options search.SearcherOptions) (
+	*DisjunctionSearcher, error) {
+	return newDisjunctionSearcher(indexReader, qsearchers, min, options,
+		true)
+}
+
+func newDisjunctionSearcher(indexReader index.IndexReader,
+	qsearchers []search.Searcher, min float64, options search.SearcherOptions,
+	limit bool) (
+	*DisjunctionSearcher, error) {
+	if limit && tooManyClauses(len(qsearchers)) {
 		return nil, tooManyClausesErr()
 	}
 	// build the downstream searchers
@@ -70,7 +81,7 @@ func NewDisjunctionSearcher(indexReader index.IndexReader, qsearchers []search.S
 		searchers:    searchers,
 		numSearchers: len(searchers),
 		currs:        make([]*search.DocumentMatch, len(searchers)),
-		scorer:       scorer.NewDisjunctionQueryScorer(explain),
+		scorer:       scorer.NewDisjunctionQueryScorer(options),
 		min:          int(min),
 		matching:     make([]*search.DocumentMatch, len(searchers)),
 		matchingIdxs: make([]int, len(searchers)),
@@ -161,7 +172,8 @@ func (s *DisjunctionSearcher) SetQueryNorm(qnorm float64) {
 	}
 }
 
-func (s *DisjunctionSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
+func (s *DisjunctionSearcher) Next(ctx *search.SearchContext) (
+	*search.DocumentMatch, error) {
 	if !s.initialized {
 		err := s.initSearchers(ctx)
 		if err != nil {
@@ -199,7 +211,8 @@ func (s *DisjunctionSearcher) Next(ctx *search.SearchContext) (*search.DocumentM
 	return rv, nil
 }
 
-func (s *DisjunctionSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
+func (s *DisjunctionSearcher) Advance(ctx *search.SearchContext,
+	ID index.IndexInternalID) (*search.DocumentMatch, error) {
 	if !s.initialized {
 		err := s.initSearchers(ctx)
 		if err != nil {

vendor/github.com/blevesearch/bleve/search/searcher/search_docid.go

@@ -28,13 +28,13 @@ type DocIDSearcher struct {
 }
 
 func NewDocIDSearcher(indexReader index.IndexReader, ids []string, boost float64,
-	explain bool) (searcher *DocIDSearcher, err error) {
+	options search.SearcherOptions) (searcher *DocIDSearcher, err error) {
 
 	reader, err := indexReader.DocIDReaderOnly(ids)
 	if err != nil {
 		return nil, err
 	}
-	scorer := scorer.NewConstantScorer(1.0, boost, explain)
+	scorer := scorer.NewConstantScorer(1.0, boost, options)
 	return &DocIDSearcher{
 		scorer: scorer,
 		reader: reader,

vendor/github.com/blevesearch/bleve/search/searcher/search_filter.go

@@ -0,0 +1,88 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package searcher
+
+import (
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/search"
+)
+
+// FilterFunc defines a function which can filter documents
+// returning true means keep the document
+// returning false means do not keep the document
+type FilterFunc func(d *search.DocumentMatch) bool
+
+// FilteringSearcher wraps any other searcher, but checks any Next/Advance
+// call against the supplied FilterFunc
+type FilteringSearcher struct {
+	child  search.Searcher
+	accept FilterFunc
+}
+
+func NewFilteringSearcher(s search.Searcher, filter FilterFunc) *FilteringSearcher {
+	return &FilteringSearcher{
+		child:  s,
+		accept: filter,
+	}
+}
+
+func (f *FilteringSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
+	next, err := f.child.Next(ctx)
+	for next != nil && err == nil {
+		if f.accept(next) {
+			return next, nil
+		}
+		next, err = f.child.Next(ctx)
+	}
+	return nil, err
+}
+
+func (f *FilteringSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
+	adv, err := f.child.Advance(ctx, ID)
+	if err != nil {
+		return nil, err
+	}
+	if adv == nil {
+		return nil, nil
+	}
+	if f.accept(adv) {
+		return adv, nil
+	}
+	return f.Next(ctx)
+}
+
+func (f *FilteringSearcher) Close() error {
+	return f.child.Close()
+}
+
+func (f *FilteringSearcher) Weight() float64 {
+	return f.child.Weight()
+}
+
+func (f *FilteringSearcher) SetQueryNorm(n float64) {
+	f.child.SetQueryNorm(n)
+}
+
+func (f *FilteringSearcher) Count() uint64 {
+	return f.child.Count()
+}
+
+func (f *FilteringSearcher) Min() int {
+	return f.child.Min()
+}
+
+func (f *FilteringSearcher) DocumentMatchPoolSize() int {
+	return f.child.DocumentMatchPoolSize()
+}

vendor/github.com/blevesearch/bleve/search/searcher/search_fuzzy.go

@@ -19,17 +19,9 @@ import (
 	"github.com/blevesearch/bleve/search"
 )
 
-type FuzzySearcher struct {
-	indexReader index.IndexReader
-	term        string
-	prefix      int
-	fuzziness   int
-	field       string
-	explain     bool
-	searcher    *DisjunctionSearcher
-}
-
-func NewFuzzySearcher(indexReader index.IndexReader, term string, prefix, fuzziness int, field string, boost float64, explain bool) (*FuzzySearcher, error) {
+func NewFuzzySearcher(indexReader index.IndexReader, term string,
+	prefix, fuzziness int, field string, boost float64,
+	options search.SearcherOptions) (search.Searcher, error) {
 	// Note: we don't byte slice the term for a prefix because of runes.
 	prefixTerm := ""
 	for i, r := range term {
@@ -40,46 +32,18 @@ func NewFuzzySearcher(indexReader index.IndexReader, term string, prefix, fuzzin
 		}
 	}
 
-	candidateTerms, err := findFuzzyCandidateTerms(indexReader, term, fuzziness, field, prefixTerm)
+	candidateTerms, err := findFuzzyCandidateTerms(indexReader, term, fuzziness,
+		field, prefixTerm)
 	if err != nil {
 		return nil, err
 	}
 
-	// enumerate all the terms in the range
-	qsearchers := make([]search.Searcher, 0, len(candidateTerms))
-	qsearchersClose := func() {
-		for _, searcher := range qsearchers {
-			_ = searcher.Close()
-		}
-	}
-	for _, cterm := range candidateTerms {
-		qsearcher, err := NewTermSearcher(indexReader, cterm, field, boost, explain)
-		if err != nil {
-			qsearchersClose()
-			return nil, err
-		}
-		qsearchers = append(qsearchers, qsearcher)
-	}
-
-	// build disjunction searcher of these ranges
-	searcher, err := NewDisjunctionSearcher(indexReader, qsearchers, 0, explain)
-	if err != nil {
-		qsearchersClose()
-		return nil, err
-	}
-
-	return &FuzzySearcher{
-		indexReader: indexReader,
-		term:        term,
-		prefix:      prefix,
-		fuzziness:   fuzziness,
-		field:       field,
-		explain:     explain,
-		searcher:    searcher,
-	}, nil
+	return NewMultiTermSearcher(indexReader, candidateTerms, field,
+		boost, options, true)
 }
 
-func findFuzzyCandidateTerms(indexReader index.IndexReader, term string, fuzziness int, field, prefixTerm string) (rv []string, err error) {
+func findFuzzyCandidateTerms(indexReader index.IndexReader, term string,
+	fuzziness int, field, prefixTerm string) (rv []string, err error) {
 	rv = make([]string, 0)
 	var fieldDict index.FieldDict
 	if len(prefixTerm) > 0 {
@@ -108,36 +72,3 @@ func findFuzzyCandidateTerms(indexReader index.IndexReader, term string, fuzzine
 
 	return rv, err
 }
-
-func (s *FuzzySearcher) Count() uint64 {
-	return s.searcher.Count()
-}
-
-func (s *FuzzySearcher) Weight() float64 {
-	return s.searcher.Weight()
-}
-
-func (s *FuzzySearcher) SetQueryNorm(qnorm float64) {
-	s.searcher.SetQueryNorm(qnorm)
-}
-
-func (s *FuzzySearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
-	return s.searcher.Next(ctx)
-
-}
-
-func (s *FuzzySearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
-	return s.searcher.Advance(ctx, ID)
-}
-
-func (s *FuzzySearcher) Close() error {
-	return s.searcher.Close()
-}
-
-func (s *FuzzySearcher) Min() int {
-	return 0
-}
-
-func (s *FuzzySearcher) DocumentMatchPoolSize() int {
-	return s.searcher.DocumentMatchPoolSize()
-}

vendor/github.com/blevesearch/bleve/search/searcher/search_geoboundingbox.go

@@ -0,0 +1,173 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package searcher
+
+import (
+	"github.com/blevesearch/bleve/document"
+	"github.com/blevesearch/bleve/geo"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/numeric"
+	"github.com/blevesearch/bleve/search"
+)
+
+func NewGeoBoundingBoxSearcher(indexReader index.IndexReader, minLon, minLat,
+	maxLon, maxLat float64, field string, boost float64,
+	options search.SearcherOptions, checkBoundaries bool) (
+	search.Searcher, error) {
+
+	// track list of opened searchers, for cleanup on early exit
+	var openedSearchers []search.Searcher
+	cleanupOpenedSearchers := func() {
+		for _, s := range openedSearchers {
+			_ = s.Close()
+		}
+	}
+
+	// do math to produce list of terms needed for this search
+	onBoundaryTerms, notOnBoundaryTerms := ComputeGeoRange(0, (geo.GeoBits<<1)-1,
+		minLon, minLat, maxLon, maxLat, checkBoundaries)
+
+	var onBoundarySearcher search.Searcher
+	if len(onBoundaryTerms) > 0 {
+		rawOnBoundarySearcher, err := NewMultiTermSearcherBytes(indexReader,
+			onBoundaryTerms, field, boost, options, false)
+		if err != nil {
+			return nil, err
+		}
+		// add filter to check points near the boundary
+		onBoundarySearcher = NewFilteringSearcher(rawOnBoundarySearcher,
+			buildRectFilter(indexReader, field, minLon, minLat, maxLon, maxLat))
+		openedSearchers = append(openedSearchers, onBoundarySearcher)
+	}
+
+	var notOnBoundarySearcher search.Searcher
+	if len(notOnBoundaryTerms) > 0 {
+		var err error
+		notOnBoundarySearcher, err = NewMultiTermSearcherBytes(indexReader,
+			notOnBoundaryTerms, field, boost, options, false)
+		if err != nil {
+			cleanupOpenedSearchers()
+			return nil, err
+		}
+		openedSearchers = append(openedSearchers, notOnBoundarySearcher)
+	}
+
+	if onBoundarySearcher != nil && notOnBoundarySearcher != nil {
+		rv, err := NewDisjunctionSearcher(indexReader,
+			[]search.Searcher{
+				onBoundarySearcher,
+				notOnBoundarySearcher,
+			},
+			0, options)
+		if err != nil {
+			cleanupOpenedSearchers()
+			return nil, err
+		}
+		return rv, nil
+	} else if onBoundarySearcher != nil {
+		return onBoundarySearcher, nil
+	} else if notOnBoundarySearcher != nil {
+		return notOnBoundarySearcher, nil
+	}
+
+	return NewMatchNoneSearcher(indexReader)
+}
+
+var geoMaxShift = document.GeoPrecisionStep * 4
+var geoDetailLevel = ((geo.GeoBits << 1) - geoMaxShift) / 2
+
+func ComputeGeoRange(term uint64, shift uint,
+	sminLon, sminLat, smaxLon, smaxLat float64,
+	checkBoundaries bool) (
+	onBoundary [][]byte, notOnBoundary [][]byte) {
+	split := term | uint64(0x1)<<shift
+	var upperMax uint64
+	if shift < 63 {
+		upperMax = term | ((uint64(1) << (shift + 1)) - 1)
+	} else {
+		upperMax = 0xffffffffffffffff
+	}
+	lowerMax := split - 1
+	onBoundary, notOnBoundary = relateAndRecurse(term, lowerMax, shift,
+		sminLon, sminLat, smaxLon, smaxLat, checkBoundaries)
+	plusOnBoundary, plusNotOnBoundary := relateAndRecurse(split, upperMax, shift,
+		sminLon, sminLat, smaxLon, smaxLat, checkBoundaries)
+	onBoundary = append(onBoundary, plusOnBoundary...)
+	notOnBoundary = append(notOnBoundary, plusNotOnBoundary...)
+	return
+}
+
+func relateAndRecurse(start, end uint64, res uint,
+	sminLon, sminLat, smaxLon, smaxLat float64,
+	checkBoundaries bool) (
+	onBoundary [][]byte, notOnBoundary [][]byte) {
+	minLon := geo.MortonUnhashLon(start)
+	minLat := geo.MortonUnhashLat(start)
+	maxLon := geo.MortonUnhashLon(end)
+	maxLat := geo.MortonUnhashLat(end)
+
+	level := ((geo.GeoBits << 1) - res) >> 1
+
+	within := res%document.GeoPrecisionStep == 0 &&
+		geo.RectWithin(minLon, minLat, maxLon, maxLat,
+			sminLon, sminLat, smaxLon, smaxLat)
+	if within || (level == geoDetailLevel &&
+		geo.RectIntersects(minLon, minLat, maxLon, maxLat,
+			sminLon, sminLat, smaxLon, smaxLat)) {
+		if !within && checkBoundaries {
+			return [][]byte{
+				numeric.MustNewPrefixCodedInt64(int64(start), res),
+			}, nil
+		}
+		return nil,
+			[][]byte{
+				numeric.MustNewPrefixCodedInt64(int64(start), res),
+			}
+	} else if level < geoDetailLevel &&
+		geo.RectIntersects(minLon, minLat, maxLon, maxLat,
+			sminLon, sminLat, smaxLon, smaxLat) {
+		return ComputeGeoRange(start, res-1, sminLon, sminLat, smaxLon, smaxLat,
+			checkBoundaries)
+	}
+	return nil, nil
+}
+
+func buildRectFilter(indexReader index.IndexReader, field string,
+	minLon, minLat, maxLon, maxLat float64) FilterFunc {
+	return func(d *search.DocumentMatch) bool {
+		var lon, lat float64
+		var found bool
+		err := indexReader.DocumentVisitFieldTerms(d.IndexInternalID,
+			[]string{field}, func(field string, term []byte) {
+				// only consider the values which are shifted 0
+				prefixCoded := numeric.PrefixCoded(term)
+				shift, err := prefixCoded.Shift()
+				if err == nil && shift == 0 {
+					var i64 int64
+					i64, err = prefixCoded.Int64()
+					if err == nil {
+						lon = geo.MortonUnhashLon(uint64(i64))
+						lat = geo.MortonUnhashLat(uint64(i64))
+						found = true
+					}
+				}
+			})
+		if err == nil && found {
+			return geo.BoundingBoxContains(lon, lat,
+				minLon, minLat, maxLon, maxLat)
+		}
+		return false
+	}
+}

vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go

@@ -0,0 +1,117 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package searcher
+
+import (
+	"github.com/blevesearch/bleve/geo"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/numeric"
+	"github.com/blevesearch/bleve/search"
+)
+
+func NewGeoPointDistanceSearcher(indexReader index.IndexReader, centerLon,
+	centerLat, dist float64, field string, boost float64,
+	options search.SearcherOptions) (search.Searcher, error) {
+	// compute bounding box containing the circle
+	topLeftLon, topLeftLat, bottomRightLon, bottomRightLat, err :=
+		geo.RectFromPointDistance(centerLon, centerLat, dist)
+	if err != nil {
+		return nil, err
+	}
+
+	// build a searcher for the box
+	boxSearcher, err := boxSearcher(indexReader,
+		topLeftLon, topLeftLat, bottomRightLon, bottomRightLat,
+		field, boost, options)
+	if err != nil {
+		return nil, err
+	}
+
+	// wrap it in a filtering searcher which checks the actual distance
+	return NewFilteringSearcher(boxSearcher,
+		buildDistFilter(indexReader, field, centerLon, centerLat, dist)), nil
+}
+
+// boxSearcher builds a searcher for the described bounding box
+// if the desired box crosses the dateline, it is automatically split into
+// two boxes joined through a disjunction searcher
+func boxSearcher(indexReader index.IndexReader,
+	topLeftLon, topLeftLat, bottomRightLon, bottomRightLat float64,
+	field string, boost float64, options search.SearcherOptions) (
+	search.Searcher, error) {
+	if bottomRightLon < topLeftLon {
+		// cross date line, rewrite as two parts
+
+		leftSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+			-180, bottomRightLat, bottomRightLon, topLeftLat,
+			field, boost, options, false)
+		if err != nil {
+			return nil, err
+		}
+		rightSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+			topLeftLon, bottomRightLat, 180, topLeftLat, field, boost, options, false)
+		if err != nil {
+			_ = leftSearcher.Close()
+			return nil, err
+		}
+
+		boxSearcher, err := NewDisjunctionSearcher(indexReader,
+			[]search.Searcher{leftSearcher, rightSearcher}, 0, options)
+		if err != nil {
+			_ = leftSearcher.Close()
+			_ = rightSearcher.Close()
+			return nil, err
+		}
+		return boxSearcher, nil
+	}
+
+	// build geoboundinggox searcher for that bounding box
+	boxSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+		topLeftLon, bottomRightLat, bottomRightLon, topLeftLat, field, boost,
+		options, false)
+	if err != nil {
+		return nil, err
+	}
+	return boxSearcher, nil
+}
+
+func buildDistFilter(indexReader index.IndexReader, field string,
+	centerLon, centerLat, maxDist float64) FilterFunc {
+	return func(d *search.DocumentMatch) bool {
+		var lon, lat float64
+		var found bool
+		err := indexReader.DocumentVisitFieldTerms(d.IndexInternalID,
+			[]string{field}, func(field string, term []byte) {
+				// only consider the values which are shifted 0
+				prefixCoded := numeric.PrefixCoded(term)
+				shift, err := prefixCoded.Shift()
+				if err == nil && shift == 0 {
+					i64, err := prefixCoded.Int64()
+					if err == nil {
+						lon = geo.MortonUnhashLon(uint64(i64))
+						lat = geo.MortonUnhashLat(uint64(i64))
+						found = true
+					}
+				}
+			})
+		if err == nil && found {
+			dist := geo.Haversin(lon, lat, centerLon, centerLat)
+			if dist <= maxDist/1000 {
+				return true
+			}
+		}
+		return false
+	}
+}

vendor/github.com/blevesearch/bleve/search/searcher/search_match_all.go

@@ -27,7 +27,7 @@ type MatchAllSearcher struct {
 	count       uint64
 }
 
-func NewMatchAllSearcher(indexReader index.IndexReader, boost float64, explain bool) (*MatchAllSearcher, error) {
+func NewMatchAllSearcher(indexReader index.IndexReader, boost float64, options search.SearcherOptions) (*MatchAllSearcher, error) {
 	reader, err := indexReader.DocIDReaderAll()
 	if err != nil {
 		return nil, err
@@ -37,7 +37,7 @@ func NewMatchAllSearcher(indexReader index.IndexReader, boost float64, explain b
 		_ = reader.Close()
 		return nil, err
 	}
-	scorer := scorer.NewConstantScorer(1.0, boost, explain)
+	scorer := scorer.NewConstantScorer(1.0, boost, options)
 	return &MatchAllSearcher{
 		indexReader: indexReader,
 		reader:      reader,

vendor/github.com/blevesearch/bleve/search/searcher/search_multi_term.go

@@ -0,0 +1,85 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package searcher
+
+import (
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/search"
+)
+
+func NewMultiTermSearcher(indexReader index.IndexReader, terms []string,
+	field string, boost float64, options search.SearcherOptions, limit bool) (
+	search.Searcher, error) {
+	qsearchers := make([]search.Searcher, len(terms))
+	qsearchersClose := func() {
+		for _, searcher := range qsearchers {
+			if searcher != nil {
+				_ = searcher.Close()
+			}
+		}
+	}
+	for i, term := range terms {
+		var err error
+		qsearchers[i], err = NewTermSearcher(indexReader, term, field, boost, options)
+		if err != nil {
+			qsearchersClose()
+			return nil, err
+		}
+	}
+	// build disjunction searcher of these ranges
+	return newMultiTermSearcherBytes(indexReader, qsearchers, field, boost,
+		options, limit)
+}
+
+func NewMultiTermSearcherBytes(indexReader index.IndexReader, terms [][]byte,
+	field string, boost float64, options search.SearcherOptions, limit bool) (
+	search.Searcher, error) {
+	qsearchers := make([]search.Searcher, len(terms))
+	qsearchersClose := func() {
+		for _, searcher := range qsearchers {
+			if searcher != nil {
+				_ = searcher.Close()
+			}
+		}
+	}
+	for i, term := range terms {
+		var err error
+		qsearchers[i], err = NewTermSearcherBytes(indexReader, term, field, boost, options)
+		if err != nil {
+			qsearchersClose()
+			return nil, err
+		}
+	}
+	return newMultiTermSearcherBytes(indexReader, qsearchers, field, boost,
+		options, limit)
+}
+
+func newMultiTermSearcherBytes(indexReader index.IndexReader,
+	searchers []search.Searcher, field string, boost float64,
+	options search.SearcherOptions, limit bool) (
+	search.Searcher, error) {
+
+	// build disjunction searcher of these ranges
+	searcher, err := newDisjunctionSearcher(indexReader, searchers, 0, options,
+		limit)
+	if err != nil {
+		for _, s := range searchers {
+			_ = s.Close()
+		}
+		return nil, err
+	}
+
+	return searcher, nil
+}

vendor/github.com/blevesearch/bleve/search/searcher/search_numeric_range.go

@@ -17,22 +17,16 @@ package searcher
 import (
 	"bytes"
 	"math"
+	"sort"
 
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/numeric"
 	"github.com/blevesearch/bleve/search"
 )
 
-type NumericRangeSearcher struct {
-	indexReader index.IndexReader
-	min         *float64
-	max         *float64
-	field       string
-	explain     bool
-	searcher    *DisjunctionSearcher
-}
-
-func NewNumericRangeSearcher(indexReader index.IndexReader, min *float64, max *float64, inclusiveMin, inclusiveMax *bool, field string, boost float64, explain bool) (*NumericRangeSearcher, error) {
+func NewNumericRangeSearcher(indexReader index.IndexReader,
+	min *float64, max *float64, inclusiveMin, inclusiveMax *bool, field string,
+	boost float64, options search.SearcherOptions) (search.Searcher, error) {
 	// account for unbounded edges
 	if min == nil {
 		negInf := math.Inf(-1)
@@ -62,64 +56,49 @@ func NewNumericRangeSearcher(indexReader index.IndexReader, min *float64, max *f
 	// FIXME hard-coded precision, should match field declaration
 	termRanges := splitInt64Range(minInt64, maxInt64, 4)
 	terms := termRanges.Enumerate()
+	if len(terms) < 1 {
+		// cannot return MatchNoneSearcher because of interaction with
+		// commit f391b991c20f02681bacd197afc6d8aed444e132
+		return NewMultiTermSearcherBytes(indexReader, terms, field, boost, options,
+			true)
+	}
+	var err error
+	terms, err = filterCandidateTerms(indexReader, terms, field)
+	if err != nil {
+		return nil, err
+	}
 	if tooManyClauses(len(terms)) {
 		return nil, tooManyClausesErr()
 	}
-	// enumerate all the terms in the range
-	qsearchers := make([]search.Searcher, len(terms))
-	qsearchersClose := func() {
-		for _, searcher := range qsearchers {
-			if searcher != nil {
-				_ = searcher.Close()
-			}
-		}
-	}
-	for i, term := range terms {
-		var err error
-		qsearchers[i], err = NewTermSearcher(indexReader, string(term), field, boost, explain)
-		if err != nil {
-			qsearchersClose()
-			return nil, err
-		}
-	}
-	// build disjunction searcher of these ranges
-	searcher, err := NewDisjunctionSearcher(indexReader, qsearchers, 0, explain)
+
+	return NewMultiTermSearcherBytes(indexReader, terms, field, boost, options,
+		true)
+}
+
+func filterCandidateTerms(indexReader index.IndexReader,
+	terms [][]byte, field string) (rv [][]byte, err error) {
+	fieldDict, err := indexReader.FieldDictRange(field, terms[0], terms[len(terms)-1])
 	if err != nil {
-		qsearchersClose()
 		return nil, err
 	}
-	return &NumericRangeSearcher{
-		indexReader: indexReader,
-		min:         min,
-		max:         max,
-		field:       field,
-		explain:     explain,
-		searcher:    searcher,
-	}, nil
-}
 
-func (s *NumericRangeSearcher) Count() uint64 {
-	return s.searcher.Count()
-}
+	// enumerate the terms and check against list of terms
+	tfd, err := fieldDict.Next()
+	for err == nil && tfd != nil {
+		termBytes := []byte(tfd.Term)
+		i := sort.Search(len(terms), func(i int) bool { return bytes.Compare(terms[i], termBytes) >= 0 })
+		if i < len(terms) && bytes.Compare(terms[i], termBytes) == 0 {
+			rv = append(rv, terms[i])
+		}
+		terms = terms[i:]
+		tfd, err = fieldDict.Next()
+	}
 
-func (s *NumericRangeSearcher) Weight() float64 {
-	return s.searcher.Weight()
-}
+	if cerr := fieldDict.Close(); cerr != nil && err == nil {
+		err = cerr
+	}
 
-func (s *NumericRangeSearcher) SetQueryNorm(qnorm float64) {
-	s.searcher.SetQueryNorm(qnorm)
-}
-
-func (s *NumericRangeSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
-	return s.searcher.Next(ctx)
-}
-
-func (s *NumericRangeSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
-	return s.searcher.Advance(ctx, ID)
-}
-
-func (s *NumericRangeSearcher) Close() error {
-	return s.searcher.Close()
+	return rv, err
 }
 
 type termRange struct {
@@ -190,7 +169,8 @@ func splitInt64Range(minBound, maxBound int64, precisionStep uint) termRanges {
 		lowerWrapped := nextMinBound < minBound
 		upperWrapped := nextMaxBound > maxBound
 
-		if shift+precisionStep >= 64 || nextMinBound > nextMaxBound || lowerWrapped || upperWrapped {
+		if shift+precisionStep >= 64 || nextMinBound > nextMaxBound ||
+			lowerWrapped || upperWrapped {
 			// We are in the lowest precision or the next precision is not available.
 			rv = append(rv, newRange(minBound, maxBound, shift))
 			// exit the split recursion loop
@@ -225,11 +205,3 @@ func newRangeBytes(minBytes, maxBytes []byte) *termRange {
 		endTerm:   maxBytes,
 	}
 }
-
-func (s *NumericRangeSearcher) Min() int {
-	return 0
-}
-
-func (s *NumericRangeSearcher) DocumentMatchPoolSize() int {
-	return s.searcher.DocumentMatchPoolSize()
-}

vendor/github.com/blevesearch/bleve/search/searcher/search_phrase.go

@@ -15,6 +15,7 @@
 package searcher
 
 import (
+	"fmt"
 	"math"
 
 	"github.com/blevesearch/bleve/index"
@@ -27,11 +28,72 @@ type PhraseSearcher struct {
 	queryNorm    float64
 	currMust     *search.DocumentMatch
 	slop         int
-	terms        []string
+	terms        [][]string
 	initialized  bool
 }
 
-func NewPhraseSearcher(indexReader index.IndexReader, mustSearcher *ConjunctionSearcher, terms []string) (*PhraseSearcher, error) {
+func NewPhraseSearcher(indexReader index.IndexReader, terms []string, field string, options search.SearcherOptions) (*PhraseSearcher, error) {
+	// turn flat terms []string into [][]string
+	mterms := make([][]string, len(terms))
+	for i, term := range terms {
+		mterms[i] = []string{term}
+	}
+	return NewMultiPhraseSearcher(indexReader, mterms, field, options)
+}
+
+func NewMultiPhraseSearcher(indexReader index.IndexReader, terms [][]string, field string, options search.SearcherOptions) (*PhraseSearcher, error) {
+	options.IncludeTermVectors = true
+	var termPositionSearchers []search.Searcher
+	for _, termPos := range terms {
+		if len(termPos) == 1 && termPos[0] != "" {
+			// single term
+			ts, err := NewTermSearcher(indexReader, termPos[0], field, 1.0, options)
+			if err != nil {
+				// close any searchers already opened
+				for _, ts := range termPositionSearchers {
+					_ = ts.Close()
+				}
+				return nil, fmt.Errorf("phrase searcher error building term searcher: %v", err)
+			}
+			termPositionSearchers = append(termPositionSearchers, ts)
+		} else if len(termPos) > 1 {
+			// multiple terms
+			var termSearchers []search.Searcher
+			for _, term := range termPos {
+				if term == "" {
+					continue
+				}
+				ts, err := NewTermSearcher(indexReader, term, field, 1.0, options)
+				if err != nil {
+					// close any searchers already opened
+					for _, ts := range termPositionSearchers {
+						_ = ts.Close()
+					}
+					return nil, fmt.Errorf("phrase searcher error building term searcher: %v", err)
+				}
+				termSearchers = append(termSearchers, ts)
+			}
+			disjunction, err := NewDisjunctionSearcher(indexReader, termSearchers, 1, options)
+			if err != nil {
+				// close any searchers already opened
+				for _, ts := range termPositionSearchers {
+					_ = ts.Close()
+				}
+				return nil, fmt.Errorf("phrase searcher error building term position disjunction searcher: %v", err)
+			}
+			termPositionSearchers = append(termPositionSearchers, disjunction)
+		}
+	}
+
+	mustSearcher, err := NewConjunctionSearcher(indexReader, termPositionSearchers, options)
+	if err != nil {
+		// close any searchers already opened
+		for _, ts := range termPositionSearchers {
+			_ = ts.Close()
+		}
+		return nil, fmt.Errorf("phrase searcher error building conjunction searcher: %v", err)
+	}
+
 	// build our searcher
 	rv := PhraseSearcher{
 		indexReader:  indexReader,
@@ -96,68 +158,150 @@ func (s *PhraseSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch,
 		}
 	}
 
-	var rv *search.DocumentMatch
 	for s.currMust != nil {
-		rvftlm := make(search.FieldTermLocationMap, 0)
-		freq := 0
-		firstTerm := s.terms[0]
-		for field, termLocMap := range s.currMust.Locations {
-			rvtlm := make(search.TermLocationMap, 0)
-			locations, ok := termLocMap[firstTerm]
-			if ok {
-			OUTER:
-				for _, location := range locations {
-					crvtlm := make(search.TermLocationMap, 0)
-				INNER:
-					for i := 0; i < len(s.terms); i++ {
-						nextTerm := s.terms[i]
-						if nextTerm != "" {
-							// look through all these term locations
-							// to try and find the correct offsets
-							nextLocations, ok := termLocMap[nextTerm]
-							if ok {
-								for _, nextLocation := range nextLocations {
-									if nextLocation.Pos == location.Pos+float64(i) && nextLocation.SameArrayElement(location) {
-										// found a location match for this term
-										crvtlm.AddLocation(nextTerm, nextLocation)
-										continue INNER
-									}
-								}
-								// if we got here we didn't find a location match for this term
-								continue OUTER
-							} else {
-								continue OUTER
-							}
-						}
-					}
-					// if we got here all the terms matched
-					freq++
-					search.MergeTermLocationMaps(rvtlm, crvtlm)
-					rvftlm[field] = rvtlm
-				}
-			}
-		}
-
-		if freq > 0 {
-			// return match
-			rv = s.currMust
-			rv.Locations = rvftlm
-			err := s.advanceNextMust(ctx)
-			if err != nil {
-				return nil, err
-			}
-			return rv, nil
-		}
+		// check this match against phrase constraints
+		rv := s.checkCurrMustMatch(ctx)
 
+		// prepare for next iteration (either loop or subsequent call to Next())
 		err := s.advanceNextMust(ctx)
 		if err != nil {
 			return nil, err
 		}
+
+		// if match satisfied phrase constraints return it as a hit
+		if rv != nil {
+			return rv, nil
+		}
 	}
 
 	return nil, nil
 }
 
+// checkCurrMustMatch is soley concerned with determining if the DocumentMatch
+// pointed to by s.currMust (which satisifies the pre-condition searcher)
+// also satisfies the phase constraints.  if so, it returns a DocumentMatch
+// for this document, otherwise nil
+func (s *PhraseSearcher) checkCurrMustMatch(ctx *search.SearchContext) *search.DocumentMatch {
+	rvftlm := make(search.FieldTermLocationMap, 0)
+	freq := 0
+	// typically we would expect there to only actually be results in
+	// one field, but we allow for this to not be the case
+	// but, we note that phrase constraints can only be satisfied within
+	// a single field, so we can check them each independently
+	for field, tlm := range s.currMust.Locations {
+
+		f, rvtlm := s.checkCurrMustMatchField(ctx, tlm)
+		if f > 0 {
+			freq += f
+			rvftlm[field] = rvtlm
+		}
+	}
+
+	if freq > 0 {
+		// return match
+		rv := s.currMust
+		rv.Locations = rvftlm
+		return rv
+	}
+
+	return nil
+}
+
+// checkCurrMustMatchField is soley concerned with determining if one particular
+// field within the currMust DocumentMatch Locations satisfies the phase
+// constraints (possibly more than once).  if so, the number of times it was
+// satisfied, and these locations are returned.  otherwise 0 and either
+// a nil or empty TermLocationMap
+func (s *PhraseSearcher) checkCurrMustMatchField(ctx *search.SearchContext, tlm search.TermLocationMap) (int, search.TermLocationMap) {
+	paths := findPhrasePaths(0, nil, s.terms, tlm, nil, 0)
+	rv := make(search.TermLocationMap, len(s.terms))
+	for _, p := range paths {
+		p.MergeInto(rv)
+	}
+	return len(paths), rv
+}
+
+type phrasePart struct {
+	term string
+	loc  *search.Location
+}
+
+type phrasePath []*phrasePart
+
+func (p phrasePath) MergeInto(in search.TermLocationMap) {
+	for _, pp := range p {
+		in[pp.term] = append(in[pp.term], pp.loc)
+	}
+}
+
+// findPhrasePaths is a function to identify phase matches from a set of known
+// term locations.  the implementation is recursive, so care must be taken
+// with arguments and return values.
+//
+// prev - the previous location, nil on first invocation
+// phraseTerms - slice containing the phrase terms themselves
+//               may contain empty string as placeholder (don't care)
+// tlm - the Term Location Map containing all relevant term locations
+// offset - the offset from the previous that this next term must match
+// p - the current path being explored (appended to in recursive calls)
+//     this is the primary state being built during the traversal
+//
+// returns slice of paths, or nil if invocation did not find any successul paths
+func findPhrasePaths(prevPos uint64, ap search.ArrayPositions, phraseTerms [][]string, tlm search.TermLocationMap, p phrasePath, remainingSlop int) []phrasePath {
+
+	// no more terms
+	if len(phraseTerms) < 1 {
+		return []phrasePath{p}
+	}
+
+	car := phraseTerms[0]
+	cdr := phraseTerms[1:]
+
+	// empty term is treated as match (continue)
+	if len(car) == 0 || (len(car) == 1 && car[0] == "") {
+		nextPos := prevPos + 1
+		if prevPos == 0 {
+			// if prevPos was 0, don't set it to 1 (as thats not a real abs pos)
+			nextPos = 0 // don't advance nextPos if prevPos was 0
+		}
+		return findPhrasePaths(nextPos, ap, cdr, tlm, p, remainingSlop)
+	}
+
+	var rv []phrasePath
+	// locations for this term
+	for _, carTerm := range car {
+		locations := tlm[carTerm]
+		for _, loc := range locations {
+			if prevPos != 0 && !loc.ArrayPositions.Equals(ap) {
+				// if the array positions are wrong, can't match, try next location
+				continue
+			}
+
+			// compute distance from previous phrase term
+			dist := 0
+			if prevPos != 0 {
+				dist = editDistance(prevPos+1, loc.Pos)
+			}
+
+			// if enough slop reamining, continue recursively
+			if prevPos == 0 || (remainingSlop-dist) >= 0 {
+				// this location works, add it to the path (but not for empty term)
+				px := append(p, &phrasePart{term: carTerm, loc: loc})
+				rv = append(rv, findPhrasePaths(loc.Pos, loc.ArrayPositions, cdr, tlm, px, remainingSlop-dist)...)
+			}
+		}
+	}
+	return rv
+}
+
+func editDistance(p1, p2 uint64) int {
+	dist := int(p1 - p2)
+	if dist < 0 {
+		return -dist
+	}
+	return dist
+}
+
 func (s *PhraseSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
 	if !s.initialized {
 		err := s.initSearchers(ctx)

vendor/github.com/blevesearch/bleve/search/searcher/search_regexp.go

@@ -21,7 +21,14 @@ import (
 	"github.com/blevesearch/bleve/search"
 )
 
-func NewRegexpSearcher(indexReader index.IndexReader, pattern *regexp.Regexp, field string, boost float64, explain bool) (search.Searcher, error) {
+// NewRegexpSearcher creates a searcher which will match documents that
+// contain terms which match the pattern regexp.  The match must be EXACT
+// matching the entire term.  The provided regexp SHOULD NOT start with ^
+// or end with $ as this can intefere with the implementation.  Separately,
+// matches will be checked to ensure they match the entire term.
+func NewRegexpSearcher(indexReader index.IndexReader, pattern *regexp.Regexp,
+	field string, boost float64, options search.SearcherOptions) (
+	search.Searcher, error) {
 
 	prefixTerm, complete := pattern.LiteralPrefix()
 	var candidateTerms []string
@@ -30,39 +37,19 @@ func NewRegexpSearcher(indexReader index.IndexReader, pattern *regexp.Regexp, fi
 		candidateTerms = []string{prefixTerm}
 	} else {
 		var err error
-		candidateTerms, err = findRegexpCandidateTerms(indexReader, pattern, field, prefixTerm)
+		candidateTerms, err = findRegexpCandidateTerms(indexReader, pattern, field,
+			prefixTerm)
 		if err != nil {
 			return nil, err
 		}
 	}
 
-	// enumerate all the terms in the range
-	qsearchers := make([]search.Searcher, 0, len(candidateTerms))
-	qsearchersClose := func() {
-		for _, searcher := range qsearchers {
-			_ = searcher.Close()
-		}
-	}
-	for _, cterm := range candidateTerms {
-		qsearcher, err := NewTermSearcher(indexReader, cterm, field, boost, explain)
-		if err != nil {
-			qsearchersClose()
-			return nil, err
-		}
-		qsearchers = append(qsearchers, qsearcher)
-	}
-
-	// build disjunction searcher of these ranges
-	searcher, err := NewDisjunctionSearcher(indexReader, qsearchers, 0, explain)
-	if err != nil {
-		qsearchersClose()
-		return nil, err
-	}
-
-	return searcher, err
+	return NewMultiTermSearcher(indexReader, candidateTerms, field, boost,
+		options, true)
 }
 
-func findRegexpCandidateTerms(indexReader index.IndexReader, pattern *regexp.Regexp, field, prefixTerm string) (rv []string, err error) {
+func findRegexpCandidateTerms(indexReader index.IndexReader,
+	pattern *regexp.Regexp, field, prefixTerm string) (rv []string, err error) {
 	rv = make([]string, 0)
 	var fieldDict index.FieldDict
 	if len(prefixTerm) > 0 {
@@ -79,7 +66,8 @@ func findRegexpCandidateTerms(indexReader index.IndexReader, pattern *regexp.Reg
 	// enumerate the terms and check against regexp
 	tfd, err := fieldDict.Next()
 	for err == nil && tfd != nil {
-		if pattern.MatchString(tfd.Term) {
+		matchPos := pattern.FindStringIndex(tfd.Term)
+		if matchPos != nil && matchPos[0] == 0 && matchPos[1] == len(tfd.Term) {
 			rv = append(rv, tfd.Term)
 			if tooManyClauses(len(rv)) {
 				return rv, tooManyClausesErr()

vendor/github.com/blevesearch/bleve/search/searcher/search_term.go

@@ -22,16 +22,13 @@ import (
 
 type TermSearcher struct {
 	indexReader index.IndexReader
-	term        string
-	field       string
 	reader      index.TermFieldReader
 	scorer      *scorer.TermQueryScorer
 	tfd         index.TermFieldDoc
-	explain     bool
 }
 
-func NewTermSearcher(indexReader index.IndexReader, term string, field string, boost float64, explain bool) (*TermSearcher, error) {
-	reader, err := indexReader.TermFieldReader([]byte(term), field, true, true, true)
+func NewTermSearcher(indexReader index.IndexReader, term string, field string, boost float64, options search.SearcherOptions) (*TermSearcher, error) {
+	reader, err := indexReader.TermFieldReader([]byte(term), field, true, true, options.IncludeTermVectors)
 	if err != nil {
 		return nil, err
 	}
@@ -40,12 +37,27 @@ func NewTermSearcher(indexReader index.IndexReader, term string, field string, b
 		_ = reader.Close()
 		return nil, err
 	}
-	scorer := scorer.NewTermQueryScorer(term, field, boost, count, reader.Count(), explain)
+	scorer := scorer.NewTermQueryScorer([]byte(term), field, boost, count, reader.Count(), options)
+	return &TermSearcher{
+		indexReader: indexReader,
+		reader:      reader,
+		scorer:      scorer,
+	}, nil
+}
+
+func NewTermSearcherBytes(indexReader index.IndexReader, term []byte, field string, boost float64, options search.SearcherOptions) (*TermSearcher, error) {
+	reader, err := indexReader.TermFieldReader(term, field, true, true, options.IncludeTermVectors)
+	if err != nil {
+		return nil, err
+	}
+	count, err := indexReader.DocCount()
+	if err != nil {
+		_ = reader.Close()
+		return nil, err
+	}
+	scorer := scorer.NewTermQueryScorer(term, field, boost, count, reader.Count(), options)
 	return &TermSearcher{
 		indexReader: indexReader,
-		term:        term,
-		field:       field,
-		explain:     explain,
 		reader:      reader,
 		scorer:      scorer,
 	}, nil

vendor/github.com/blevesearch/bleve/search/searcher/search_term_prefix.go

@@ -19,93 +19,21 @@ import (
 	"github.com/blevesearch/bleve/search"
 )
 
-type TermPrefixSearcher struct {
-	indexReader index.IndexReader
-	prefix      string
-	field       string
-	explain     bool
-	searcher    *DisjunctionSearcher
-}
-
-func NewTermPrefixSearcher(indexReader index.IndexReader, prefix string, field string, boost float64, explain bool) (*TermPrefixSearcher, error) {
+func NewTermPrefixSearcher(indexReader index.IndexReader, prefix string,
+	field string, boost float64, options search.SearcherOptions) (
+	search.Searcher, error) {
 	// find the terms with this prefix
 	fieldDict, err := indexReader.FieldDictPrefix(field, []byte(prefix))
 	if err != nil {
 		return nil, err
 	}
 
-	// enumerate all the terms in the range
-	qsearchers := make([]search.Searcher, 0, 25)
-	qsearchersClose := func() {
-		for _, searcher := range qsearchers {
-			_ = searcher.Close()
-		}
-	}
-
+	var terms []string
 	tfd, err := fieldDict.Next()
 	for err == nil && tfd != nil {
-		var qsearcher *TermSearcher
-		qsearcher, err = NewTermSearcher(indexReader, string(tfd.Term), field, 1.0, explain)
-		if err != nil {
-			qsearchersClose()
-			_ = fieldDict.Close()
-			return nil, err
-		}
-		qsearchers = append(qsearchers, qsearcher)
+		terms = append(terms, tfd.Term)
 		tfd, err = fieldDict.Next()
 	}
 
-	err = fieldDict.Close()
-	if err != nil {
-		qsearchersClose()
-		return nil, err
-	}
-
-	// build disjunction searcher of these ranges
-	searcher, err := NewDisjunctionSearcher(indexReader, qsearchers, 0, explain)
-	if err != nil {
-		qsearchersClose()
-		return nil, err
-	}
-
-	return &TermPrefixSearcher{
-		indexReader: indexReader,
-		prefix:      prefix,
-		field:       field,
-		explain:     explain,
-		searcher:    searcher,
-	}, nil
-}
-
-func (s *TermPrefixSearcher) Count() uint64 {
-	return s.searcher.Count()
-}
-
-func (s *TermPrefixSearcher) Weight() float64 {
-	return s.searcher.Weight()
-}
-
-func (s *TermPrefixSearcher) SetQueryNorm(qnorm float64) {
-	s.searcher.SetQueryNorm(qnorm)
-}
-
-func (s *TermPrefixSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
-	return s.searcher.Next(ctx)
-
-}
-
-func (s *TermPrefixSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
-	return s.searcher.Advance(ctx, ID)
-}
-
-func (s *TermPrefixSearcher) Close() error {
-	return s.searcher.Close()
-}
-
-func (s *TermPrefixSearcher) Min() int {
-	return 0
-}
-
-func (s *TermPrefixSearcher) DocumentMatchPoolSize() int {
-	return s.searcher.DocumentMatchPoolSize()
+	return NewMultiTermSearcher(indexReader, terms, field, boost, options, true)
 }

vendor/github.com/blevesearch/bleve/search/searcher/search_term_range.go

@@ -0,0 +1,79 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package searcher
+
+import (
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/search"
+)
+
+func NewTermRangeSearcher(indexReader index.IndexReader,
+	min, max []byte, inclusiveMin, inclusiveMax *bool, field string,
+	boost float64, options search.SearcherOptions) (search.Searcher, error) {
+
+	if inclusiveMin == nil {
+		defaultInclusiveMin := true
+		inclusiveMin = &defaultInclusiveMin
+	}
+	if inclusiveMax == nil {
+		defaultInclusiveMax := false
+		inclusiveMax = &defaultInclusiveMax
+	}
+
+	if min == nil {
+		min = []byte{}
+	}
+
+	rangeMax := max
+	if rangeMax != nil {
+		// the term dictionary range end has an unfortunate implementation
+		rangeMax = append(rangeMax, 0)
+	}
+
+	// find the terms with this prefix
+	fieldDict, err := indexReader.FieldDictRange(field, min, rangeMax)
+	if err != nil {
+		return nil, err
+	}
+
+	var terms []string
+	tfd, err := fieldDict.Next()
+	for err == nil && tfd != nil {
+		terms = append(terms, tfd.Term)
+		tfd, err = fieldDict.Next()
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	if len(terms) < 1 {
+		return NewMatchNoneSearcher(indexReader)
+	}
+
+	if !*inclusiveMin && min != nil && string(min) == terms[0] {
+		terms = terms[1:]
+		// check again, as we might have removed only entry
+		if len(terms) < 1 {
+			return NewMatchNoneSearcher(indexReader)
+		}
+	}
+
+	// if our term list included the max, it would be the last item
+	if !*inclusiveMax && max != nil && string(max) == terms[len(terms)-1] {
+		terms = terms[:len(terms)-1]
+	}
+
+	return NewMultiTermSearcher(indexReader, terms, field, boost, options, true)
+}