forked from hashicorp/terraform
/
marshal_equal.go
40 lines (34 loc) · 1.15 KB
/
marshal_equal.go
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package statefile
import (
"bytes"
"github.com/hugorut/terraform/src/states"
)
// StatesMarshalEqual returns true if and only if the two given states have
// an identical (byte-for-byte) statefile representation.
//
// This function compares only the portions of the state that are persisted
// in state files, so for example it will not return false if the only
// differences between the two states are local values or descendent module
// outputs.
func StatesMarshalEqual(a, b *states.State) bool {
var aBuf bytes.Buffer
var bBuf bytes.Buffer
// nil states are not valid states, and so they can never martial equal.
if a == nil || b == nil {
return false
}
// We write here some temporary files that have no header information
// populated, thus ensuring that we're only comparing the state itself
// and not any metadata.
err := Write(&File{State: a}, &aBuf)
if err != nil {
// Should never happen, because we're writing to an in-memory buffer
panic(err)
}
err = Write(&File{State: b}, &bBuf)
if err != nil {
// Should never happen, because we're writing to an in-memory buffer
panic(err)
}
return bytes.Equal(aBuf.Bytes(), bBuf.Bytes())
}