Fix bug when deleting range queries

When performing a range query on an array when deleting, the items which were supposed to be removed, ended up being the ones which were kept.

Not the ramining array items are kept instead when deleting.

util/data/data.go

@@ -111,6 +111,20 @@ func (d *Doc) path(path ...string) (paths []string) {
 
 }
 
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
 func trim(s string) string {
 	if s[0] == '[' && s[len(s)-1] == ']' {
 		return s[1 : len(s)-1]
@@ -158,7 +172,7 @@ func (d *Doc) what(p string, a []interface{}, t int8) (o []interface{}, i []int,
 	}
 
 	// Split the specified array index
-	// by commas, so that we can get
+	// by colons, so that we can get
 	// the specified array items.
 
 	c := strings.Count(p, ":")
@@ -216,6 +230,7 @@ func (d *Doc) what(p string, a []interface{}, t int8) (o []interface{}, i []int,
 	if c == 1 {
 
 		var e error
+		var s, f int
 
 		b := []int{0, len(a)}
 		x := strings.Split(p, ":")
@@ -234,9 +249,24 @@ func (d *Doc) what(p string, a []interface{}, t int8) (o []interface{}, i []int,
 			}
 		}
 
-		for k := b[0]; k < b[1] && k < len(a); k++ {
+		s = b[0]
+		s = max(s, 0)
+		s = min(s, len(a))
+
+		f = b[1]
+		f = max(f, 0)
+		f = min(f, len(a))
+
+		if t == choose {
+			for k, v := range a[s:f] {
 				i = append(i, k)
-			o = append(o, a[k])
+				o = append(o, v)
+			}
+		} else {
+			for k, v := range append(a[:s], a[f+1:]...) {
+				i = append(i, k)
+				o = append(o, v)
+			}
 		}
 
 		return o, i, many

util/data/data_test.go

@@ -760,6 +760,20 @@ func TestOperations(t *testing.T) {
 		So(doc.Get("the.item.tags.length").Data(), ShouldResemble, 0)
 	})
 
+	Convey("Can del single from array", t, func() {
+		_, err := doc.Inc([]interface{}{"Hot", "Humid", "Sticky", "Warm", "Snowy", "Icy"}, "the.item.tags")
+		So(err, ShouldBeNil)
+		So(doc.Get("the.item.tags").Data(), ShouldResemble, []interface{}{"Hot", "Humid", "Sticky", "Warm", "Snowy", "Icy"})
+		So(doc.Get("the.item.tags.length").Data(), ShouldResemble, 6)
+	})
+
+	Convey("Can del single from array", t, func() {
+		err := doc.Del("the.item.tags[0:3]")
+		So(err, ShouldBeNil)
+		So(doc.Get("the.item.tags").Data(), ShouldResemble, []interface{}{"Snowy", "Icy"})
+		So(doc.Get("the.item.tags.length").Data(), ShouldResemble, 2)
+	})
+
 	Convey("Can del array", t, func() {
 		err := doc.Del("the.item.tags")
 		So(err, ShouldBeNil)