Fix index diffing algorithm

util/indx/indx.go

@@ -21,16 +21,29 @@ import (
 	"github.com/abcum/surreal/util/data"
 )
 
-func Diff(old, now [][]interface{}) (_, _ [][]interface{}) {
+func Diff(old, now [][]interface{}) (del, add [][]interface{}) {
 
-	for i := len(old) - 1; i >= 0; i-- {
+loopo:
-		if reflect.DeepEqual(old[i], now[i]) {
+	for _, ov := range old {
-			old = append(old[:i], old[i+1:]...)
+		for _, nv := range now {
-			now = append(now[:i], now[i+1:]...)
+			if reflect.DeepEqual(ov, nv) {
+				continue loopo
+			}
 		}
+		del = append(del, ov)
 	}
 
-	return old, now
+loopn:
+	for _, nv := range now {
+		for _, ov := range old {
+			if reflect.DeepEqual(ov, nv) {
+				continue loopn
+			}
+		}
+		add = append(add, nv)
+	}
+
+	return
 
 }
 

util/indx/indx_test.go

@@ -36,12 +36,14 @@ func TestDiff(t *testing.T) {
 		}
 		So(old, ShouldHaveLength, 2)
 		So(now, ShouldHaveLength, 2)
-		old, now = Diff(old, now)
+		del, add := Diff(old, now)
-		So(old, ShouldHaveLength, 0)
+		So(del, ShouldHaveLength, 0)
-		So(now, ShouldHaveLength, 0)
+		So(del, ShouldResemble, [][]interface{}(nil))
+		So(add, ShouldHaveLength, 0)
+		So(add, ShouldResemble, [][]interface{}(nil))
 	})
 
-	Convey("Perform diff of different arrays", t, func() {
+	Convey("Perform diff of reversed arrays", t, func() {
 		old := [][]interface{}{
 			{"one", "two"},
 			{"two", "tre"},
@@ -52,9 +54,11 @@ func TestDiff(t *testing.T) {
 		}
 		So(old, ShouldHaveLength, 2)
 		So(now, ShouldHaveLength, 2)
-		old, now = Diff(old, now)
+		del, add := Diff(old, now)
-		So(old, ShouldHaveLength, 2)
+		So(del, ShouldHaveLength, 0)
-		So(now, ShouldHaveLength, 2)
+		So(del, ShouldResemble, [][]interface{}(nil))
+		So(add, ShouldHaveLength, 0)
+		So(add, ShouldResemble, [][]interface{}(nil))
 	})
 
 	Convey("Perform diff of same and different arrays", t, func() {
@@ -64,13 +68,33 @@ func TestDiff(t *testing.T) {
 		}
 		now := [][]interface{}{
 			{"two", "tre"},
-			{"two", "tre"},
+			{"one", "tre"},
 		}
 		So(old, ShouldHaveLength, 2)
 		So(now, ShouldHaveLength, 2)
-		old, now = Diff(old, now)
+		del, add := Diff(old, now)
-		So(old, ShouldHaveLength, 1)
+		So(del, ShouldHaveLength, 1)
+		So(del, ShouldResemble, [][]interface{}{{"one", "two"}})
+		So(add, ShouldHaveLength, 1)
+		So(add, ShouldResemble, [][]interface{}{{"one", "tre"}})
+	})
+
+	Convey("Perform diff of same and different length arrays", t, func() {
+		old := [][]interface{}{
+			{"one", "two"},
+			{"two", "tre"},
+			{"one", "tre"},
+		}
+		now := [][]interface{}{
+			{"two", "tre"},
+		}
+		So(old, ShouldHaveLength, 3)
 		So(now, ShouldHaveLength, 1)
+		del, add := Diff(old, now)
+		So(del, ShouldHaveLength, 2)
+		So(del, ShouldResemble, [][]interface{}{{"one", "two"}, {"one", "tre"}})
+		So(add, ShouldHaveLength, 0)
+		So(add, ShouldResemble, [][]interface{}(nil))
 	})
 
 }
@@ -140,4 +164,40 @@ func TestBuild(t *testing.T) {
 
 	})
 
+	Convey("Perform build with empty array field", t, func() {
+
+		col := sql.Idents{
+			sql.NewIdent("test.*"),
+		}
+
+		doc := data.Consume(map[string]interface{}{
+			"test": []interface{}{},
+		})
+
+		out := Build(col, doc)
+
+		So(out, ShouldResemble, [][]interface{}(nil))
+
+	})
+
+	Convey("Perform build with non-empty array field", t, func() {
+
+		col := sql.Idents{
+			sql.NewIdent("test.*"),
+		}
+
+		doc := data.Consume(map[string]interface{}{
+			"test": []interface{}{"one", "two", "tre"},
+		})
+
+		out := Build(col, doc)
+
+		So(out, ShouldResemble, [][]interface{}{
+			{"one"},
+			{"two"},
+			{"tre"},
+		})
+
+	})
+
 }