fix #512. Group by should respect null values

CHANGELOG.md

@@ -3,6 +3,7 @@
 ### Bugfixes
 
 - [Issue #511](https://github.com/influxdb/influxdb/issues/511). Don't automatically create the database when a db user is created
+- [Issue #512](https://github.com/influxdb/influxdb/issues/512). Group by should respect null values
 - [Issue #369](https://github.com/influxdb/influxdb/issues/369). Fix some edge cases with WAL recovery
 
 ## v0.6.1 [2014-05-06]

src/integration/data_test.go

@@ -96,6 +96,36 @@ func (self *DataTestSuite) TestAll(c *C) {
 
 type Fun func(client Client)
 
+// issue #512
+func (self *DataTestSuite) GroupByNullValues(c *C) (Fun, Fun) {
+	// make sure we exceed the pointBatchSize, so we force a yield to
+	// the filtering engine
+	return func(client Client) {
+			data := `
+[
+  {
+    "points": [
+        ["one", null],
+        ["one", 1],
+        ["one", null]
+    ],
+    "name": "test_null_groups",
+    "columns": ["column0", "column1"]
+  }
+]`
+			client.WriteJsonData(data, c, influxdb.Second)
+		}, func(client Client) {
+			serieses := client.RunQuery("select count(column0) from test_null_groups group by column1", c, "m")
+			c.Assert(serieses, HasLen, 1)
+			maps := ToMap(serieses[0])
+			c.Assert(maps, HasLen, 2)
+			c.Assert(maps[0]["count"], Equals, 1.0)
+			// this is an implementation detail, but nulls come last in the
+			// trie
+			c.Assert(maps[1]["count"], Equals, 2.0)
+		}
+}
+
 // issue #389
 func (self *DataTestSuite) FilteringShouldNotStopIfAllPointsDontMatch(c *C) (Fun, Fun) {
 	// make sure we exceed the pointBatchSize, so we force a yield to

src/protocol/protocol_extensions.go

@@ -179,7 +179,7 @@ func (self *FieldValue) Equals(other *FieldValue) bool {
 		}
 		return *other.StringValue == *self.StringValue
 	}
-	return false
+	return other.GetIsNull()
 }
 
 // defines total order on FieldValue, the following is true
@@ -211,5 +211,5 @@ func (self *FieldValue) GreaterOrEqual(other *FieldValue) bool {
 		}
 		return *self.StringValue >= *other.StringValue
 	}
-	return other.BoolValue == nil && other.Int64Value == nil && other.DoubleValue == nil && other.StringValue == nil
+	return true
 }