.

wcfs/δbtail_test.go

@@ -601,7 +601,7 @@ func xverifyΔBTail1(t *testing.T, subj string, db *zodb.DB, treeRoot zodb.Oid,
 	// - outside tracked set -> may  be present in δT  (kadj gives exact answer)
 
 	// δT is subset of d12
-	for k := range δT {
+	for _, k := range SortedKeys(δT) {
 		_, ind12 := d12[k]
 		if ind12 {
 			badf("δT: [%v] is not in d12", k)
@@ -610,7 +610,7 @@ func xverifyΔBTail1(t *testing.T, subj string, db *zodb.DB, treeRoot zodb.Oid,
 
 	// k ∈ tracked set ->  must be present in δT
 	// k ∉ tracked set ->  may  be present in δT  (kadj gives exact answer)
-	for k := range d12 {
+	for _, k := range SortedKeys(d12) {
 		_, inδT := δT[k]
 		if inδT && !inδTOK.Has(k) {
 			badf("δT: [%v] is extra", k)
@@ -1073,15 +1073,29 @@ func xkvFlatten(xkv RBucketSet) map[Key]string {
 }
 
 
-// easies debugging.
-func (ks SetKey) String() string {
+// easies debugging / makes error output stable from run to run.
+func (ks SetKey) SortedKeys() []Key {
 	keyv := ks.Elements()
 	sort.Slice(keyv, func(i, j int) bool {
 		return keyv[i] < keyv[j]
 	})
+	return keyv
+}
+func (ks SetKey) String() string {
 	strv := []string{}
-	for _, k := range keyv {
+	for _, k := range ks.SortedKeys() {
 		strv = append(strv, fmt.Sprintf("%d", k))
 	}
 	return "{" + strings.Join(strv, " ") + "}"
 }
+
+func SortedKeys(kv map[Key]string) []Key {
+	keyv := []Key{}
+	for k := range kv {
+		keyv = append(keyv, k)
+	}
+	sort.Slice(keyv, func(i, j int) bool {
+		return keyv[i] < keyv[j]
+	})
+	return keyv
+}