fix(core): Fix regression in computing cond variables (#9126)

Fixes: #9125

Author: Harshil Goel

graphql/e2e/schema/schema_test.go

@@ -42,9 +42,9 @@ import (
 )
 
 var (
-	groupOneHTTP   = testutil.ContainerAddr("alpha1", 8080)
-	groupTwoHTTP   = testutil.ContainerAddr("alpha2", 8080)
-	groupThreeHTTP = testutil.ContainerAddr("alpha3", 8080)
+	groupOneHTTP   = testutil.ContainerAddr0("alpha1", 8080)
+	groupTwoHTTP   = testutil.ContainerAddr0("alpha2", 8080)
+	groupThreeHTTP = testutil.ContainerAddr0("alpha3", 8080)
 	groupOnegRPC   = testutil.SockAddr
 
 	groupOneGraphQLServer   = "http://" + groupOneHTTP + "/graphql"

query/common_test.go

@@ -345,6 +345,19 @@ tweet-c                        : string @index(fulltext) .
 tweet-d                        : string @index(trigram) .
 name2                          : string @index(term)  .
 age2                           : int @index(int) .
+
+DispatchBoard.column: uid @reverse .
+order: int .
+
+type DispatchBoardColumn {
+  name
+}
+
+type DispatchBoardCard {
+  DispatchBoard.column
+  order
+}
+
 `
 
 func populateCluster(dc dgraphapi.Cluster) {
@@ -892,6 +905,16 @@ func populateCluster(dc dgraphapi.Cluster) {
 
 		<40> <name2> "Alice" .
 		<41> <age2> "20" .
+
+		<1023> <dgraph.type> "DispatchBoardColumn" .
+                <1024> <dgraph.type> "DispatchBoardColumn" .
+                <1025> <dgraph.type> "DispatchBoardCard" .
+                <1026> <dgraph.type> "DispatchBoardCard" .
+
+                <1025> <DispatchBoard.column> <1023> .
+                <1025> <order> "0" .
+                <1026> <DispatchBoard.column> <1023> .
+                <1026> <order> "1" .
 	`)
 	x.Panic(err)
 

query/query.go

@@ -1185,13 +1185,6 @@ func (sg *SubGraph) transformVars(doneVars map[string]varValue, path []*SubGraph
 			mt.Const = val
 			continue
 		}
-		// TODO: Need to understand why certain aggregations map to uid = 0
-		// while others map to uid = MaxUint64
-		if val, ok := newMap[0]; ok && len(newMap) == 1 {
-			mt.Const = val
-			continue
-		}
-
 		mt.Val = newMap
 	}
 	return nil

query/query0_test.go

@@ -3547,6 +3547,46 @@ func TestEqFilterWithoutIndex(t *testing.T) {
 
 }
 
+func TestCondCondition(t *testing.T) {
+	tests := []struct {
+		name     string
+		query    string
+		expected string
+	}{
+		{
+			`Test Cond`,
+			`{
+			   var(func: uid(0x3ff)) {
+                             columnUid as uid
+                             ~DispatchBoard.column { o as order }
+                             cards as count(~DispatchBoard.column)
+                           }
+
+			   var() {
+                             lastPosition as max(val(o))
+                             cardCount as max(val(cards))
+                             nextPosition as math(cond(cardCount==0, 0, lastPosition+1))
+                           }
+
+                           q(func: uid(columnUid)) {
+                             val(lastPosition)
+                             val(cardCount)
+                             val(nextPosition)
+                             uid
+                           }
+			 }`,
+			`{"data":{"q": [{"uid": "0x3ff"}] }}`,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			result := processQueryNoErr(t, tc.query)
+			require.JSONEq(t, tc.expected, result)
+		})
+	}
+}
+
 func TestMatchingWithPagination(t *testing.T) {
 	tests := []struct {
 		name     string

testutil/docker.go

@@ -208,14 +208,22 @@ func AllContainers(prefix string) []types.Container {
 	return out
 }
 
-func ContainerAddr(name string, privatePort uint16) string {
+func ContainerAddrWithHost(name string, privatePort uint16, host string) string {
 	c := getContainer(name)
 	for _, p := range c.Ports {
 		if p.PrivatePort == privatePort {
-			return "localhost:" + strconv.Itoa(int(p.PublicPort))
+			return host + ":" + strconv.Itoa(int(p.PublicPort))
 		}
 	}
-	return "localhost:" + strconv.Itoa(int(privatePort))
+	return host + ":" + strconv.Itoa(int(privatePort))
+}
+
+func ContainerAddr0(name string, privatePort uint16) string {
+	return ContainerAddrWithHost(name, privatePort, "0.0.0.0")
+}
+
+func ContainerAddr(name string, privatePort uint16) string {
+	return ContainerAddrWithHost(name, privatePort, "localhost")
 }
 
 // DockerStart starts the specified services.