From ceb66119570e874ffb1e2be07771bdc75b182da9 Mon Sep 17 00:00:00 2001
From: "Matt T. Proud" <matt.proud@gmail.com>
Date: Thu, 21 Mar 2013 17:09:17 +0100
Subject: [PATCH] Fix regression in subsequent range op. compactions.

We have an anomaly whereby subsequent range operations fail to be
compacted into one single range operation.  This fixes such
behavior.
---
 storage/metric/operation.go      | 12 ++--
 storage/metric/operation_test.go | 96 ++++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+), 8 deletions(-)

diff --git a/storage/metric/operation.go b/storage/metric/operation.go
index 71dc929363..c111620582 100644
--- a/storage/metric/operation.go
+++ b/storage/metric/operation.go
@@ -431,16 +431,12 @@ func optimizeForward(pending ops) (out ops) {
 				continue
 			case *getValuesAlongRangeOp:
 				// Range queries should be concatenated if they overlap.
-				pending = pending[1:len(pending)]
-
 				if next.GreedierThan(t) {
-					t.through = next.through
+					next.from = t.from
 
-					var (
-						head = ops{t}
-					)
-
-					pending = append(head, pending...)
+					return optimizeForward(pending)
+				} else {
+					pending = pending[1:len(pending)]
 				}
 			case *getValuesAtIntervalOp:
 				pending = pending[1:len(pending)]
diff --git a/storage/metric/operation_test.go b/storage/metric/operation_test.go
index eaa5824029..27741f251d 100644
--- a/storage/metric/operation_test.go
+++ b/storage/metric/operation_test.go
@@ -321,6 +321,46 @@ func testOptimizeTimeGroups(t test.Tester) {
 					},
 				},
 			},
+			// Regression Validation 1: Multiple Overlapping Interval Requests
+			//                          This one specific case expects no mutation.
+			{
+				in: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(15 * time.Second),
+						through: testInstant.Add(15 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(30 * time.Second),
+						through: testInstant.Add(30 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(45 * time.Second),
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+				out: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(15 * time.Second),
+						through: testInstant.Add(15 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(30 * time.Second),
+						through: testInstant.Add(30 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(45 * time.Second),
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+			},
 		}
 	)
 
@@ -518,6 +558,34 @@ func testOptimizeForward(t test.Tester) {
 					},
 				},
 			},
+			// Regression Validation 1: Multiple Overlapping Interval Requests
+			//                          We expect to find compaction.
+			{
+				in: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(15 * time.Second),
+						through: testInstant.Add(15 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(30 * time.Second),
+						through: testInstant.Add(30 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(45 * time.Second),
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+				out: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+			},
 		}
 	)
 
@@ -1007,6 +1075,34 @@ func testOptimize(t test.Tester) {
 					},
 				},
 			},
+			// Regression Validation 1: Multiple Overlapping Interval Requests
+			//                          We expect to find compaction.
+			{
+				in: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(15 * time.Second),
+						through: testInstant.Add(15 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(30 * time.Second),
+						through: testInstant.Add(30 * time.Second).Add(5 * time.Minute),
+					},
+					&getValuesAlongRangeOp{
+						from:    testInstant.Add(45 * time.Second),
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+				out: ops{
+					&getValuesAlongRangeOp{
+						from:    testInstant,
+						through: testInstant.Add(45 * time.Second).Add(5 * time.Minute),
+					},
+				},
+			},
 		}
 	)