make delete idempotent

fixes ipfs/go-datastore#104

datastore.go

@@ -99,16 +99,6 @@ func (d *accessor) GetSize(key ds.Key) (size int, err error) {
 }
 
 func (a *accessor) Delete(key ds.Key) (err error) {
-	// leveldb Delete will not return an error if the key doesn't
-	// exist (see https://github.com/syndtr/goleveldb/issues/109),
-	// so check that the key exists first and if not return an
-	// error
-	exists, err := a.ldb.Has(key.Bytes(), nil)
-	if !exists {
-		return ds.ErrNotFound
-	} else if err != nil {
-		return err
-	}
 	return a.ldb.Delete(key.Bytes(), nil)
 }
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/ipfs/go-ds-leveldb
 
 require (
-	github.com/ipfs/go-datastore v0.0.3
+	github.com/ipfs/go-datastore v0.1.0
 	github.com/syndtr/goleveldb v1.0.0
 )

go.sum

@@ -10,8 +10,8 @@ github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
-github.com/ipfs/go-datastore v0.0.3 h1:/eP3nMDmLzMJNoWSSYvEkmMTTrm9FFCN+JraP9NdlwU=
-github.com/ipfs/go-datastore v0.0.3/go.mod h1:d4KVXhMt913cLBEI/PXAy6ko+W7e9AhyAKBGh803qeE=
+github.com/ipfs/go-datastore v0.1.0 h1:TOxI04l8CmO4zGtesENhzm4PwkFwJXY3rKiYaaMf9fI=
+github.com/ipfs/go-datastore v0.1.0/go.mod h1:d4KVXhMt913cLBEI/PXAy6ko+W7e9AhyAKBGh803qeE=
 github.com/ipfs/go-ipfs-delay v0.0.0-20181109222059-70721b86a9a8/go.mod h1:8SP1YXK1M1kXuc4KJZINY3TQQ03J2rwBG9QfXmbRPrw=
 github.com/jbenet/goprocess v0.0.0-20160826012719-b497e2f366b8 h1:bspPhN+oKYFk5fcGNuQzp6IGzYQSenLEgH3s6jkXrWw=
 github.com/jbenet/goprocess v0.0.0-20160826012719-b497e2f366b8/go.mod h1:Ly/wlsjFq/qrU3Rar62tu1gASgGw6chQbSh/XgIIXCY=