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Author: zhangchiqing

storage/operation/reads_test.go

@@ -73,6 +73,7 @@ func TestIterateInvalidRange(t *testing.T) {
 	})
 }
 
+// TestIterationBoundary tests that when the prefixEnd is all 1s, the iteration should include the last key
 func TestIterationBoundary(t *testing.T) {
 	dbtest.RunWithStorages(t, func(t *testing.T, r storage.Reader, withWriter dbtest.WithWriter) {
 		// Define the prefix range

storage/operations.go

@@ -150,6 +150,8 @@ func OnCommitSucceed(b ReaderBatchWriter, onSuccessFn func()) {
 // for instance, to iterate keys between "hello" and "world",
 // we use "hello" as LowerBound, "worle" as UpperBound, so that "world", "world1", "worldffff...ffff"
 // will all be included.
+// In the case that the endPrefix is all 1s, such as []byte{0xff, 0xff, ...}, there is no upper-bound,
+// it returns (startPrefix, nil, false)
 func StartEndPrefixToLowerUpperBound(startPrefix, endPrefix []byte) (lowerBound, upperBound []byte, hasUpperBound bool) {
 	// if the endPrefix is all 1s, such as []byte{0xff, 0xff, ...}, there is no upper-bound
 	// so we return the startPrefix as the lower-bound, and nil as the upper-bound, and false for hasUpperBound