only create one provisioner instance per type

There's no reason to start individual provisioners per module path, as
they are not configured per module (or independently at all for that
matter).

terraform/eval_context_builtin.go

@@ -225,14 +225,12 @@ func (ctx *BuiltinEvalContext) InitProvisioner(n string) (provisioners.Interface
 	ctx.ProvisionerLock.Lock()
 	defer ctx.ProvisionerLock.Unlock()
 
-	key := PathObjectCacheKey(ctx.Path(), n)
-
-	p, err := ctx.Components.ResourceProvisioner(n, key)
+	p, err := ctx.Components.ResourceProvisioner(n, "")
 	if err != nil {
 		return nil, err
 	}
 
-	ctx.ProvisionerCache[key] = p
+	ctx.ProvisionerCache[n] = p
 
 	return p, nil
 }
@@ -243,8 +241,7 @@ func (ctx *BuiltinEvalContext) Provisioner(n string) provisioners.Interface {
 	ctx.ProvisionerLock.Lock()
 	defer ctx.ProvisionerLock.Unlock()
 
-	key := PathObjectCacheKey(ctx.Path(), n)
-	return ctx.ProvisionerCache[key]
+	return ctx.ProvisionerCache[n]
 }
 
 func (ctx *BuiltinEvalContext) ProvisionerSchema(n string) *configschema.Block {
@@ -259,9 +256,7 @@ func (ctx *BuiltinEvalContext) CloseProvisioner(n string) error {
 	ctx.ProvisionerLock.Lock()
 	defer ctx.ProvisionerLock.Unlock()
 
-	key := PathObjectCacheKey(ctx.Path(), n)
-
-	prov := ctx.ProvisionerCache[key]
+	prov := ctx.ProvisionerCache[n]
 	if prov != nil {
 		return prov.Close()
 	}

terraform/transform_provisioner.go

@@ -4,8 +4,6 @@ import (
 	"fmt"
 	"log"
 
-	"github.com/hashicorp/terraform/addrs"
-
 	"github.com/hashicorp/go-multierror"
 	"github.com/hashicorp/terraform/dag"
 )
@@ -43,16 +41,15 @@ func (t *ProvisionerTransformer) Transform(g *Graph) error {
 	for _, v := range g.Vertices() {
 		if pv, ok := v.(GraphNodeProvisionerConsumer); ok {
 			for _, p := range pv.ProvisionedBy() {
-				key := provisionerMapKey(p, pv)
-				if m[key] == nil {
+				if m[p] == nil {
 					err = multierror.Append(err, fmt.Errorf(
 						"%s: provisioner %s couldn't be found",
 						dag.VertexName(v), p))
 					continue
 				}
 
-				log.Printf("[TRACE] ProvisionerTransformer: %s is provisioned by %s (%q)", dag.VertexName(v), key, dag.VertexName(m[key]))
-				g.Connect(dag.BasicEdge(v, m[key]))
+				log.Printf("[TRACE] ProvisionerTransformer: %s is provisioned by %s (%q)", dag.VertexName(v), p, dag.VertexName(m[p]))
+				g.Connect(dag.BasicEdge(v, m[p]))
 			}
 		}
 	}
@@ -85,18 +82,8 @@ func (t *MissingProvisionerTransformer) Transform(g *Graph) error {
 			continue
 		}
 
-		// If this node has a subpath, then we use that as a prefix
-		// into our map to check for an existing provider.
-		path := addrs.RootModuleInstance
-		if sp, ok := pv.(GraphNodeSubPath); ok {
-			path = sp.Path()
-		}
-
 		for _, p := range pv.ProvisionedBy() {
-			// Build the key for storing in the map
-			key := provisionerMapKey(p, pv)
-
-			if _, ok := m[key]; ok {
+			if _, ok := m[p]; ok {
 				// This provisioner already exists as a configure node
 				continue
 			}
@@ -110,12 +97,11 @@ func (t *MissingProvisionerTransformer) Transform(g *Graph) error {
 			// Build the vertex
 			var newV dag.Vertex = &NodeProvisioner{
 				NameValue: p,
-				PathValue: path,
 			}
 
 			// Add the missing provisioner node to the graph
-			m[key] = g.Add(newV)
-			log.Printf("[TRACE] MissingProviderTransformer: added implicit provisioner %s, first implied by %s", key, dag.VertexName(v))
+			m[p] = g.Add(newV)
+			log.Printf("[TRACE] MissingProviderTransformer: added implicit provisioner %s, first implied by %s", p, dag.VertexName(v))
 		}
 	}
 
@@ -153,23 +139,11 @@ func (t *CloseProvisionerTransformer) Transform(g *Graph) error {
 	return nil
 }
 
-// provisionerMapKey is a helper that gives us the key to use for the
-// maps returned by things such as provisionerVertexMap.
-func provisionerMapKey(k string, v dag.Vertex) string {
-	pathPrefix := ""
-	if sp, ok := v.(GraphNodeSubPath); ok {
-		pathPrefix = sp.Path().String() + "."
-	}
-
-	return pathPrefix + k
-}
-
 func provisionerVertexMap(g *Graph) map[string]dag.Vertex {
 	m := make(map[string]dag.Vertex)
 	for _, v := range g.Vertices() {
 		if pv, ok := v.(GraphNodeProvisioner); ok {
-			key := provisionerMapKey(pv.ProvisionerName(), v)
-			m[key] = v
+			m[pv.ProvisionerName()] = v
 		}
 	}