fix windows tests (#469)

Signed-off-by: Krasi Georgiev <kgeorgie@redhat.com>

.travis.yml

@@ -2,6 +2,10 @@
 sudo: required
 dist: trusty
 language: go
+os:
+  - windows
+  - linux
+  - osx
 
 go:
   - 1.10.x
@@ -9,9 +13,12 @@ go:
 
 go_import_path: github.com/prometheus/tsdb
 
+before_install:
+  - if [[ "$TRAVIS_OS_NAME" == "windows" ]]; then choco install make; fi
+  
 install:
   - go get -v -t ./...
 
 script:
   # `staticcheck` target is omitted due to linting errors
-  - make check_license style unused test
+  - if [[ "$TRAVIS_OS_NAME" == "windows" ]]; then make test; else make style unused test; fi

head.go

@@ -473,14 +473,13 @@ func (h *Head) Init(minValidTime int64) error {
 	if err != nil {
 		return errors.Wrap(err, "open WAL segments")
 	}
-	defer sr.Close()
 
 	err = h.loadWAL(wal.NewReader(sr))
+	sr.Close() // Close the reader so that if there was an error the repair can remove the corrupted file under Windows.
 	if err == nil {
 		return nil
 	}
 	level.Warn(h.logger).Log("msg", "encountered WAL error, attempting repair", "err", err)
-
 	if err := h.wal.Repair(err); err != nil {
 		return errors.Wrap(err, "repair corrupted WAL")
 	}

head_test.go

@@ -118,11 +118,11 @@ func TestHead_ReadWAL(t *testing.T) {
 
 	w, err := wal.New(nil, nil, dir)
 	testutil.Ok(t, err)
+	defer w.Close()
 	populateTestWAL(t, w, entries)
 
 	head, err := NewHead(nil, nil, w, 1000)
 	testutil.Ok(t, err)
-	defer head.Close()
 
 	testutil.Ok(t, head.Init(math.MinInt64))
 	testutil.Equals(t, uint64(100), head.lastSeriesID)
@@ -282,11 +282,11 @@ func TestHeadDeleteSeriesWithoutSamples(t *testing.T) {
 
 	w, err := wal.New(nil, nil, dir)
 	testutil.Ok(t, err)
+	defer w.Close()
 	populateTestWAL(t, w, entries)
 
 	head, err := NewHead(nil, nil, w, 1000)
 	testutil.Ok(t, err)
-	defer head.Close()
 
 	testutil.Ok(t, head.Init(math.MinInt64))
 
@@ -389,6 +389,7 @@ Outer:
 func TestDeleteUntilCurMax(t *testing.T) {
 	numSamples := int64(10)
 	hb, err := NewHead(nil, nil, nil, 1000000)
+	defer hb.Close()
 	testutil.Ok(t, err)
 	app := hb.Appender()
 	smpls := make([]float64, numSamples)
@@ -478,6 +479,7 @@ func TestDelete_e2e(t *testing.T) {
 	defer os.RemoveAll(dir)
 	hb, err := NewHead(nil, nil, nil, 100000)
 	testutil.Ok(t, err)
+	defer hb.Close()
 	app := hb.Appender()
 	for _, l := range lbls {
 		ls := labels.New(l...)
@@ -845,6 +847,7 @@ func TestHead_LogRollback(t *testing.T) {
 
 	w, err := wal.New(nil, nil, dir)
 	testutil.Ok(t, err)
+	defer w.Close()
 	h, err := NewHead(nil, nil, w, 1000)
 	testutil.Ok(t, err)
 
@@ -911,6 +914,7 @@ func TestWalRepair(t *testing.T) {
 
 			w, err := wal.New(nil, nil, dir)
 			testutil.Ok(t, err)
+			defer w.Close()
 
 			for i := 1; i <= test.totalRecs; i++ {
 				// At this point insert a corrupted record.
@@ -936,7 +940,6 @@ func TestWalRepair(t *testing.T) {
 			}
 			testutil.Ok(t, r.Err())
 			testutil.Equals(t, test.expRecs, actRec, "Wrong number of intact records")
-
 		})
 	}
 }

wal/wal.go

@@ -298,9 +298,6 @@ func (w *WAL) Repair(origErr error) error {
 	level.Warn(w.logger).Log("msg", "deleting all segments behind corruption", "segment", cerr.Segment)
 
 	for _, s := range segs {
-		if s.index <= cerr.Segment {
-			continue
-		}
 		if w.segment.i == s.index {
 			// The active segment needs to be removed,
 			// close it first (Windows!). Can be closed safely
@@ -310,6 +307,9 @@ func (w *WAL) Repair(origErr error) error {
 				return errors.Wrap(err, "close active segment")
 			}
 		}
+		if s.index <= cerr.Segment {
+			continue
+		}
 		if err := os.Remove(filepath.Join(w.dir, s.name)); err != nil {
 			return errors.Wrapf(err, "delete segment:%v", s.index)
 		}

wal/wal_test.go

@@ -23,7 +23,6 @@ import (
 	"os"
 	"testing"
 
-	"github.com/pkg/errors"
 	"github.com/prometheus/tsdb/testutil"
 )
 
@@ -336,14 +335,8 @@ func TestWAL_Repair(t *testing.T) {
 			}
 			testutil.NotOk(t, r.Err())
 			testutil.Ok(t, sr.Close())
+
 			testutil.Ok(t, w.Repair(r.Err()))
-
-			// See https://github.com/prometheus/prometheus/issues/4603
-			// We need to close w.segment because it needs to be deleted.
-			// But this is to mainly artificially test Repair() again.
-			testutil.Ok(t, w.segment.Close())
-			testutil.Ok(t, w.Repair(errors.Wrap(r.Err(), "err")))
-
 			sr, err = NewSegmentsReader(dir)
 			testutil.Ok(t, err)
 			r = NewReader(sr)

wal_test.go

@@ -11,6 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// +build !windows
+
 package tsdb
 
 import (