chore: add errors to iterator creation (#14635)

core/CHANGELOG.md

@@ -0,0 +1,41 @@
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+
+# Changelog
+
+## [Unreleased]
+
+### API-Breaking Changes
+
+- (store)[14635](https://github.com/cosmos/cosmos-sdk/pull/14635) Add error handling to all methods on the `KVStore` interface

core/store/store.go

@@ -22,14 +22,14 @@ type KVStore interface {
 	// To iterate over entire domain, use store.Iterator(nil, nil)
 	// CONTRACT: No writes may happen within a domain while an iterator exists over it.
 	// Exceptionally allowed for cachekv.Store, safe to write in the modules.
-	Iterator(start, end []byte) Iterator
+	Iterator(start, end []byte) (Iterator, error)
 
 	// ReverseIterator iterates over a domain of keys in descending order. End is exclusive.
 	// Start must be less than end, or the Iterator is invalid.
 	// Iterator must be closed by caller.
 	// CONTRACT: No writes may happen within a domain while an iterator exists over it.
 	// Exceptionally allowed for cachekv.Store, safe to write in the modules.
-	ReverseIterator(start, end []byte) Iterator
+	ReverseIterator(start, end []byte) (Iterator, error)
 }
 
 // Iterator is an alias db's Iterator for convenience.