Adding tests around the tolerane

finder/find.go

@@ -89,12 +89,16 @@ func (t Finder) FindCtx(ctx context.Context, input string) (string, float64, boo
 	return best, hs, false
 }
 
-// meetsLengthTolerance checks if the input meets the length tolerance criteria
+// meetsLengthTolerance checks if the input meets the length tolerance criteria. The percentage is based on the input
 func meetsLengthTolerance(t float64, input, reference string) bool {
-	if t == 0 {
+	if t <= 0 {
 		return true
 	}
 
+	if t > 1 {
+		return false
+	}
+
 	inputLen := len(input)
 	refLen := len(reference)
 	threshold := int(math.Ceil(float64(inputLen) * t))

finder/find_test.go

@@ -94,6 +94,34 @@ func TestContextCancel(t *testing.T) {
 	}
 }
 
+func TestMeetsLengthTolerance(t *testing.T) {
+	testData := []struct {
+		Expect    bool
+		Input     string
+		Reference string
+		Tolerance float64
+	}{
+		{Expect: true, Input: "foo", Reference: "bar", Tolerance: -1},
+		{Expect: true, Input: "foo", Reference: "bar", Tolerance: 0},
+		{Expect: true, Input: "foo", Reference: "bar", Tolerance: 1},
+		{Expect: false, Input: "foo", Reference: "bar", Tolerance: 2}, // erroneous situation
+
+		{Expect: true, Input: "smooth", Reference: "smoothie", Tolerance: 0.2},
+		{Expect: false, Input: "smooth", Reference: "smoothie", Tolerance: 0.1},
+
+		{Expect: true, Input: "abc", Reference: "defghi", Tolerance: 0.9},
+		{Expect: true, Input: "abc", Reference: "defg", Tolerance: 0.5},
+	}
+
+	for _, td := range testData {
+		r := meetsLengthTolerance(td.Tolerance, td.Input, td.Reference)
+		if r != td.Expect {
+			t.Errorf("Expected the tolerance to be %t\n%+v", td.Expect, td)
+		}
+	}
+
+}
+
 func BenchmarkSliceOrMap(b *testing.B) {
 	size := 50
 	var hashMap = make(map[int]int, size)