impl/memory: Implement Queries

service/datastore/properties.go

Index: service/datastore/properties.go
diff --git a/service/datastore/properties.go b/service/datastore/properties.go
index 63156fe68da97b5f7ddf9f4c4600aa2c53861d49..672fdbabac68d37f90a2c18a84cf70c2cf6291f2 100644
--- a/service/datastore/properties.go
+++ b/service/datastore/properties.go
@@ -112,7 +112,7 @@ type PropertyType byte
 //   https://cloud.google.com/appengine/docs/go/datastore/entities#Go_Value_type_ordering
 // with a slight divergence for the Int/Time split.
 // NOTE: this enum can only occupy 7 bits, because we use the high bit to encode
-// indexed/non-indexed. See typData.WriteBinary.
+// indexed/non-indexed. See serialize.WriteProperty.
 const (
 	PTNull PropertyType = iota
 	PTInt
@@ -146,9 +146,19 @@ const (
 	PTKey
 	PTBlobKey
 
+	// NOTE: THIS MUST BE LAST VALUE FOR THE init() ASSERTION BELOW TO WORK.
 	PTUnknown
 )
 
+func init() {
+	if PTUnknown > 0x7f {

[dnj (Google), 2015/08/23 06:50:07]

IMO put this check in "serialize", as it owns the code that actually depends on
this condition.

[iannucci, 2015/08/23 18:19:43]

It's better here. There are actually 2 modules that rely on this behavior. I'd
rather keep with the assertion with the data that can cause the assertion
anyway. Otherwise you can change this module, and all will be well, but some
other package will break.

+		panic(
+			"PTUnknown (and therefore PropertyType) exceeds 0x7f. This conflicts " +
+				"with serialize.WriteProperty's use of the high bit to indicate " +
+				"NoIndex.")
+	}
+}
+
 func (t PropertyType) String() string {
 	switch t {
 	case PTNull: