Revert "Match spec for delegation traversal"

This reverts commit 15fee6b.

client/delegations.go

@@ -149,17 +149,22 @@ type delegation struct {
 	child  data.DelegatedRole
 }
 
+type delegationID struct {
+	parent string
+	child  string
+}
+
 type delegationsIterator struct {
-	stack        []delegation
-	file         string
-	visitedRoles map[string]struct{}
+	stack   []delegation
+	file    string
+	visited map[delegationID]struct{}
 }
 
 func newDelegationsIterator(role data.DelegatedRole, parent string, file string) *delegationsIterator {
 	i := &delegationsIterator{
-		file:         file,
-		stack:        make([]delegation, 0, 1),
-		visitedRoles: make(map[string]struct{}),
+		file:    file,
+		stack:   make([]delegation, 0, 1),
+		visited: make(map[delegationID]struct{}),
 	}
 
 	i.add([]data.DelegatedRole{role}, parent)
@@ -174,13 +179,12 @@ func (d *delegationsIterator) next() (delegation, bool) {
 	delegation := d.stack[len(d.stack)-1]
 	d.stack = d.stack[:len(d.stack)-1]
 
-	// 5.6.7.1: If this role has been visited before, then skip this role (so
-	// that cycles in the delegation graph are avoided).
-	roleName := delegation.child.Name
-	if _, ok := d.visitedRoles[roleName]; ok {
+	// 5.6.7.1 cycles protection
+	id := delegationID{delegation.parent, delegation.child.Name}
+	if _, ok := d.visited[id]; ok {
 		return d.next()
 	}
-	d.visitedRoles[roleName] = struct{}{}
+	d.visited[id] = struct{}{}
 
 	// 5.6.7.2 trim delegations to visit, only the current role and its delegations
 	// will be considered

client/delegations_test.go

@@ -102,7 +102,7 @@ func TestDelegationsIterator(t *testing.T) {
 			},
 			rootDelegation: data.DelegatedRole{Name: "a", Paths: defaultPathPatterns},
 			file:           "",
-			resultOrder:    []string{"a", "b", "d", "e"},
+			resultOrder:    []string{"a", "b", "a", "e", "d"},
 		},
 		{
 			testName: "cycle avoided 2",
@@ -122,7 +122,7 @@ func TestDelegationsIterator(t *testing.T) {
 			},
 			rootDelegation: data.DelegatedRole{Name: "a", Paths: defaultPathPatterns},
 			file:           "",
-			resultOrder:    []string{"a", "b", "c"},
+			resultOrder:    []string{"a", "a", "b", "a", "b", "c", "c"},
 		},
 		{
 			testName: "diamond delegation",
@@ -140,7 +140,7 @@ func TestDelegationsIterator(t *testing.T) {
 			},
 			rootDelegation: data.DelegatedRole{Name: "a", Paths: defaultPathPatterns},
 			file:           "",
-			resultOrder:    []string{"a", "b", "d", "c"},
+			resultOrder:    []string{"a", "b", "d", "c", "d"},
 		},
 	}