snapshot of https://github.com/blevesearch/bleve.git (master, 2026-09-15; blobs > 131072B omitted)

search/levenshtein_test.go

@@ -0,0 +1,126 @@
+//  Copyright (c) 2014 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 search
+
+import (
+	"testing"
+)
+
+func TestLevenshteinDistance(t *testing.T) {
+
+	tests := []struct {
+		a    string
+		b    string
+		dist int
+	}{
+		{
+			"water",
+			"atec",
+			2,
+		},
+		{
+			"water",
+			"aphex",
+			4,
+		},
+	}
+
+	for _, test := range tests {
+		actual := LevenshteinDistance(test.a, test.b)
+		if actual != test.dist {
+			t.Errorf("expected %d, got %d for %s and %s", test.dist, actual, test.a, test.b)
+		}
+	}
+}
+
+func TestLevenshteinDistanceMax(t *testing.T) {
+
+	tests := []struct {
+		a        string
+		b        string
+		max      int
+		dist     int
+		exceeded bool
+	}{
+		{
+			a:        "water",
+			b:        "atec",
+			max:      1,
+			dist:     1,
+			exceeded: true,
+		},
+		{
+			a:        "water",
+			b:        "christmas",
+			max:      3,
+			dist:     3,
+			exceeded: true,
+		},
+		{
+			a:        "",
+			b:        "water",
+			max:      10,
+			dist:     5,
+			exceeded: false,
+		},
+		{
+			a:        "water",
+			b:        "",
+			max:      3,
+			dist:     3,
+			exceeded: true,
+		},
+	}
+
+	for _, test := range tests {
+		actual, exceeded := LevenshteinDistanceMax(test.a, test.b, test.max)
+		if actual != test.dist || exceeded != test.exceeded {
+			t.Errorf("expected %d %t, got %d %t for %s and %s", test.dist, test.exceeded, actual, exceeded, test.a, test.b)
+		}
+	}
+}
+
+// 5 terms that are less than 2
+// 5 terms that are more than 2
+var benchmarkTerms = []string{
+	"watex",
+	"aters",
+	"wayer",
+	"wbter",
+	"yater",
+	"christmas",
+	"waterwaterwater",
+	"watcatdogfish",
+	"q",
+	"couchbase",
+}
+
+func BenchmarkLevenshteinDistance(b *testing.B) {
+	a := "water"
+	for i := 0; i < b.N; i++ {
+		for _, t := range benchmarkTerms {
+			LevenshteinDistance(a, t)
+		}
+	}
+}
+
+func BenchmarkLevenshteinDistanceMax(b *testing.B) {
+	a := "water"
+	for i := 0; i < b.N; i++ {
+		for _, t := range benchmarkTerms {
+			LevenshteinDistanceMax(a, t, 2)
+		}
+	}
+}