Properly propagate unknowns in go SDK marshaling operations (#4369)

CHANGELOG.md

@@ -53,6 +53,9 @@ CHANGELOG
 - Fix error when setting config without value in non-interactive mode
   [#4358](https://github.com/pulumi/pulumi/pull/4358)
 
+- Propagate unknowns in Go SDK during marshal operations
+  [#4369](https://github.com/pulumi/pulumi/pull/4369/files)
+
 ## 1.14.0 (2020-04-01)
 - Fix error related to side-by-side versions of `@pulumi/pulumi`.
   [#4235](https://github.com/pulumi/pulumi/pull/4235)

sdk/go/pulumi/context.go

@@ -178,9 +178,11 @@ func (ctx *Context) Invoke(tok string, args interface{}, result interface{}, opt
 		resolvedArgsMap = resolvedArgs.ObjectValue()
 	}
 
+	keepUnknowns := ctx.DryRun()
 	rpcArgs, err := plugin.MarshalProperties(
 		resolvedArgsMap,
-		plugin.MarshalOptions{KeepUnknowns: false, KeepSecrets: true})
+		plugin.MarshalOptions{KeepUnknowns: keepUnknowns, KeepSecrets: true},
+	)
 	if err != nil {
 		return fmt.Errorf("marshaling arguments: %w", err)
 	}
@@ -215,7 +217,10 @@ func (ctx *Context) Invoke(tok string, args interface{}, result interface{}, opt
 	}
 
 	// Otherwsie, simply unmarshal the output properties and return the result.
-	outProps, err := plugin.UnmarshalProperties(resp.Return, plugin.MarshalOptions{KeepSecrets: true})
+	outProps, err := plugin.UnmarshalProperties(
+		resp.Return,
+		plugin.MarshalOptions{KeepSecrets: true, KeepUnknowns: keepUnknowns},
+	)
 	if err != nil {
 		return err
 	}
@@ -693,7 +698,10 @@ func (state *resourceState) resolve(dryrun bool, err error, inputs *resourceInpu
 
 	var outprops resource.PropertyMap
 	if err == nil {
-		outprops, err = plugin.UnmarshalProperties(result, plugin.MarshalOptions{KeepSecrets: true})
+		outprops, err = plugin.UnmarshalProperties(
+			result,
+			plugin.MarshalOptions{KeepSecrets: true, KeepUnknowns: dryrun},
+		)
 	}
 	if err != nil {
 		// If there was an error, we must reject everything.