sstable: add ReadAll test util

Add a test routine to allow tests to easily read all
points/rangedels/rangekeys from an sstable.

internal/testutils/errors.go

@@ -0,0 +1,37 @@
+// Copyright 2024 The LevelDB-Go and Pebble Authors. All rights reserved. Use
+// of this source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package testutils
+
+// CheckErr can be used to simplify test code that expects no errors.
+// Instead of:
+//
+//	v, err := SomeFunc()
+//	if err != nil { .. }
+//
+// we can use:
+//
+//	v := testutils.CheckErr(someFunc())
+func CheckErr[V any](v V, err error) V {
+	if err != nil {
+		panic(err)
+	}
+	return v
+}
+
+// CheckErr2 can be used to simplify test code that expects no errors.
+// Instead of:
+//
+//	v, w, err := SomeFunc()
+//	if err != nil { .. }
+//
+// we can use:
+//
+//	v, w := testutils.CheckErr2(someFunc())
+func CheckErr2[V any, W any](v V, w W, err error) (V, W) {
+	if err != nil {
+		panic(err)
+	}
+	return v, w
+}

sstable/reader.go

@@ -265,7 +265,7 @@ type Reader struct {
 
 var _ CommonReader = (*Reader)(nil)
 
-// Close implements DB.Close, as documented in the pebble package.
+// Close the reader and the underlying objstorage.Readable.
 func (r *Reader) Close() error {
 	r.opts.Cache.Unref()
 

sstable/test_utils.go

@@ -0,0 +1,46 @@
+// Copyright 2024 The LevelDB-Go and Pebble Authors. All rights reserved. Use
+// of this source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package sstable
+
+import (
+	"github.com/cockroachdb/pebble/internal/base"
+	"github.com/cockroachdb/pebble/internal/keyspan"
+	"github.com/cockroachdb/pebble/internal/testutils"
+	"github.com/cockroachdb/pebble/objstorage"
+)
+
+// ReadAll returns all point keys, range del spans, and range key spans from an
+// sstable. Closes the Readable. Panics on errors.
+func ReadAll(
+	r objstorage.Readable,
+) (points []base.InternalKV, rangeDels, rangeKeys []keyspan.Span) {
+	reader := testutils.CheckErr(NewReader(r, ReaderOptions{}))
+	defer reader.Close()
+	pointIter := testutils.CheckErr(reader.NewIter(NoTransforms, nil /* lower */, nil /* upper */))
+	defer pointIter.Close()
+
+	for kv := pointIter.First(); kv != nil; kv = pointIter.Next() {
+		val, _ := testutils.CheckErr2(kv.Value(nil))
+		points = append(points, base.InternalKV{
+			K: kv.K.Clone(),
+			V: base.MakeInPlaceValue(val),
+		})
+	}
+
+	if rangeDelIter := testutils.CheckErr(reader.NewRawRangeDelIter(NoTransforms)); rangeDelIter != nil {
+		defer rangeDelIter.Close()
+		for s := testutils.CheckErr(rangeDelIter.First()); s != nil; s = testutils.CheckErr(rangeDelIter.Next()) {
+			rangeDels = append(rangeDels, s.DeepClone())
+		}
+	}
+
+	if rangeKeyIter := testutils.CheckErr(reader.NewRawRangeKeyIter(NoTransforms)); rangeKeyIter != nil {
+		defer rangeKeyIter.Close()
+		for s := testutils.CheckErr(rangeKeyIter.First()); s != nil; s = testutils.CheckErr(rangeKeyIter.Next()) {
+			rangeKeys = append(rangeKeys, s.DeepClone())
+		}
+	}
+	return points, rangeDels, rangeKeys
+}