From 182e7838858a39f25029cdbcb77fb433c8ded3a7 Mon Sep 17 00:00:00 2001
From: Martin Atkins <mart@degeneration.co.uk>
Date: Tue, 28 Aug 2018 16:38:37 -0700
Subject: [PATCH] core: EvalReadDataDiff to output direct config value
 alongside planned

We're now writing the "planned new value" to OutputValue, but the data
resource nodes during refresh need to see the verbatim config value in
order to decide whether read must be deferred to the apply phase, so we'll
optionally export that here too.
---
 terraform/eval_read_data.go    | 11 +++++++----
 terraform/node_data_refresh.go | 14 +++++++-------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/terraform/eval_read_data.go b/terraform/eval_read_data.go
index f9924b29e..2eb9960d3 100644
--- a/terraform/eval_read_data.go
+++ b/terraform/eval_read_data.go
@@ -22,9 +22,10 @@ type EvalReadDataDiff struct {
 	ProviderAddr   addrs.AbsProviderConfig
 	ProviderSchema **ProviderSchema
 
-	Output      **plans.ResourceInstanceChange
-	OutputValue *cty.Value
-	OutputState **states.ResourceInstanceObject
+	Output            **plans.ResourceInstanceChange
+	OutputValue       *cty.Value
+	OutputConfigValue *cty.Value
+	OutputState       **states.ResourceInstanceObject
 
 	// Set Previous when re-evaluating diff during apply, to ensure that
 	// the "Destroy" flag is preserved.
@@ -114,10 +115,12 @@ func (n *EvalReadDataDiff) Eval(ctx EvalContext) (interface{}, error) {
 	if n.Output != nil {
 		*n.Output = change
 	}
-
 	if n.OutputValue != nil {
 		*n.OutputValue = change.After
 	}
+	if n.OutputConfigValue != nil {
+		*n.OutputConfigValue = configVal
+	}
 
 	if n.OutputState != nil {
 		state := &states.ResourceInstanceObject{
diff --git a/terraform/node_data_refresh.go b/terraform/node_data_refresh.go
index 65da5dffb..1993faf2d 100644
--- a/terraform/node_data_refresh.go
+++ b/terraform/node_data_refresh.go
@@ -145,13 +145,13 @@ func (n *NodeRefreshableDataResourceInstance) EvalTree() EvalNode {
 			},
 
 			&EvalReadDataDiff{
-				Addr:           addr.Resource,
-				Config:         n.Config,
-				ProviderAddr:   n.ResolvedProvider,
-				ProviderSchema: &providerSchema,
-				Output:         &change,
-				OutputValue:    &configVal,
-				OutputState:    &state,
+				Addr:              addr.Resource,
+				Config:            n.Config,
+				ProviderAddr:      n.ResolvedProvider,
+				ProviderSchema:    &providerSchema,
+				Output:            &change,
+				OutputConfigValue: &configVal,
+				OutputState:       &state,
 			},
 
 			// The rest of this pass can proceed only if there are no