From 21596a0e17746fe4973b11a0ee2ddd8cc18173db Mon Sep 17 00:00:00 2001
From: Steve Streeting <steve@stevestreeting.com>
Date: Mon, 24 Aug 2015 15:15:16 +0100
Subject: [PATCH] Test for ScanPreviousVersions

---
 lfs/scanner_git_test.go | 82 +++++++++++++++++++++++++++++++++++++++++
 test/testutils.go       |  7 ++++
 2 files changed, 89 insertions(+)

diff --git a/lfs/scanner_git_test.go b/lfs/scanner_git_test.go
index bbb852ee..e992378d 100644
--- a/lfs/scanner_git_test.go
+++ b/lfs/scanner_git_test.go
@@ -5,7 +5,9 @@ package lfs_test // to avoid import cycles
 // which avoids import cycles with testutils
 
 import (
+	"sort"
 	"testing"
+	"time"
 
 	. "github.com/github/git-lfs/lfs"
 	"github.com/github/git-lfs/test"
@@ -74,3 +76,83 @@ func TestScanUnpushed(t *testing.T) {
 	assert.Equal(t, 0, len(pointers), "Should be 0 pointers unpushed")
 
 }
+
+func TestScanPreviousVersions(t *testing.T) {
+	repo := test.NewRepo(t)
+	repo.Pushd()
+	defer func() {
+		repo.Popd()
+		repo.Cleanup()
+	}()
+
+	now := time.Now()
+
+	inputs := []*test.CommitInput{
+		{ // 0
+			CommitDate: now.AddDate(0, 0, -20),
+			Files: []*test.FileInput{
+				{"file1.txt", 20, nil},
+				{"file2.txt", 30, nil},
+				{"folder/nested.txt", 40, nil},
+				{"folder/nested2.txt", 31, nil},
+			},
+		},
+		{ // 1
+			CommitDate: now.AddDate(0, 0, -10),
+			Files: []*test.FileInput{
+				{"file2.txt", 22, nil},
+			},
+		},
+		{ // 2
+			NewBranch:  "excluded",
+			CommitDate: now.AddDate(0, 0, -6),
+			Files: []*test.FileInput{
+				{"file2.txt", 12, nil},
+				{"folder/nested2.txt", 16, nil},
+			},
+		},
+		{ // 3
+			ParentBranches: []string{"master"},
+			CommitDate:     now.AddDate(0, 0, -4),
+			Files: []*test.FileInput{
+				{"folder/nested.txt", 42, nil},
+				{"folder/nested2.txt", 6, nil},
+			},
+		},
+		{ // 4
+			Files: []*test.FileInput{
+				{"folder/nested.txt", 22, nil},
+			},
+		},
+	}
+	outputs := repo.AddCommits(inputs)
+
+	// Previous commits excludes final state of each file, which is:
+	// file1.txt            [0] (unchanged since first commit so excluded)
+	// file2.txt            [1] (because [2] is on another branch so excluded)
+	// folder/nested.txt    [4] (updated at last commit)
+	// folder/nested2.txt   [3]
+
+	// The only changes which will be included are changes prior to final state
+	// where the '-' side of the diff is inside the date range
+
+	// 7 day limit excludes [0] commit, but includes state from that if there
+	// was a subsequent change
+	pointers, err := ScanPreviousVersions("master", now.AddDate(0, 0, -7))
+	assert.Equal(t, nil, err)
+
+	// Includes the following 'before' state at commits:
+	// folder/nested.txt [-diff at 4, ie 3, -diff at 3 ie 0]
+	// folder/nested2.txt [-diff at 3 ie 0]
+	// others are either on diff branches, before this window, or unchanged
+	expected := []*WrappedPointer{
+		{Name: "folder/nested.txt", Size: outputs[3].Files[0].Size, Pointer: outputs[3].Files[0]},
+		{Name: "folder/nested.txt", Size: outputs[0].Files[2].Size, Pointer: outputs[0].Files[2]},
+		{Name: "folder/nested2.txt", Size: outputs[0].Files[3].Size, Pointer: outputs[0].Files[3]},
+	}
+	// Need to sort to compare equality
+	sort.Sort(test.WrappedPointersByOid(expected))
+	sort.Sort(test.WrappedPointersByOid(pointers))
+	assert.Equal(t, expected, pointers)
+
+}
diff --git a/test/testutils.go b/test/testutils.go
index edabcbcb..429dbd9a 100644
--- a/test/testutils.go
+++ b/test/testutils.go
@@ -377,3 +377,10 @@ type RefsByName []*git.Ref
 func (a RefsByName) Len() int           { return len(a) }
 func (a RefsByName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
 func (a RefsByName) Less(i, j int) bool { return a[i].Name < a[j].Name }
+
+// WrappedPointersByOid implements sort.Interface for []*lfs.WrappedPointer based on oid
+type WrappedPointersByOid []*lfs.WrappedPointer
+
+func (a WrappedPointersByOid) Len() int           { return len(a) }
+func (a WrappedPointersByOid) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a WrappedPointersByOid) Less(i, j int) bool { return a[i].Pointer.Oid < a[j].Pointer.Oid }