4 files changed, 142 insertions, 27 deletions
diff --git a/internal/feed/feed.go b/internal/feed/feed.go
index 4b18b9d..98e62ef 100644
--- a/internal/feed/feed.go
+++ b/internal/feed/feed.go
@@ -29,32 +29,6 @@ const (
 
 // TODO: parse cpe
 
-// CVSS user interaction
-type UserInteraction int
-
-// Unmarshal CVSS user interaction from JSON.
-func (me *UserInteraction) UnmarshalJSON(b []byte) error {
-  // decode string, check for error
-  var s string
-  if err := json.Unmarshal(b, &s); err != nil {
-    return err
-  }
-
-  // check value
-  switch s {
-  case "NONE":
-    *me = None
-  case "REQUIRED":
-    *me = Required
-  default:
-    // return error
-    return fmt.Errorf("unknown user interaction: %s", s)
-  }
-
-  // return success
-  return nil
-}
-
 // CVSS scope
 type Scope int
 
@@ -432,7 +406,7 @@ type CvssV3 struct {
   PrivilegesRequired V3PrivilegesRequired `json:"privilegesRequired"`
 
   // user interaction
-  UserInteraction UserInteraction `json:"userInteraction"`
+  UserInteraction V3UserInteraction `json:"userInteraction"`
 
   // scope
   Scope Scope `json:"scope"`
diff --git a/internal/feed/v3userinteraction.go b/internal/feed/v3userinteraction.go
new file mode 100644
index 0000000..a6a53ca
--- /dev/null
+++ b/internal/feed/v3userinteraction.go
@@ -0,0 +1,40 @@
+package feed
+
+//go:generate stringer -linecomment -type=V3UserInteraction
+
+import (
+  "encoding/json"
+  "fmt"
+)
+
+// CVSS v3 user interaction
+type V3UserInteraction byte
+
+const (
+  V3UINone V3UserInteraction = iota // NONE
+  V3UIRequired // REQUIRED
+)
+
+// Unmarshal CVSS user interaction from JSON.
+func (me *V3UserInteraction) UnmarshalJSON(b []byte) error {
+  // decode string, check for error
+  var s string
+  if err := json.Unmarshal(b, &s); err != nil {
+    return err
+  }
+
+  // check value
+  switch s {
+  case "NONE":
+    *me = V3UINone
+  case "REQUIRED":
+    *me = V3UIRequired
+  default:
+    // return error
+    return fmt.Errorf("unknown CVSS v3 user interaction: %s", s)
+  }
+
+  // return success
+  return nil
+}
+
diff --git a/internal/feed/v3userinteraction_string.go b/internal/feed/v3userinteraction_string.go
new file mode 100644
index 0000000..be78920
--- /dev/null
+++ b/internal/feed/v3userinteraction_string.go
@@ -0,0 +1,24 @@
+// Code generated by "stringer -linecomment -type=V3UserInteraction"; DO NOT EDIT.
+
+package feed
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[V3UINone-0]
+	_ = x[V3UIRequired-1]
+}
+
+const _V3UserInteraction_name = "NONEREQUIRED"
+
+var _V3UserInteraction_index = [...]uint8{0, 4, 12}
+
+func (i V3UserInteraction) String() string {
+	if i >= V3UserInteraction(len(_V3UserInteraction_index)-1) {
+		return "V3UserInteraction(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _V3UserInteraction_name[_V3UserInteraction_index[i]:_V3UserInteraction_index[i+1]]
+}
diff --git a/internal/feed/v3userinteraction_test.go b/internal/feed/v3userinteraction_test.go
new file mode 100644
index 0000000..c5949c2
--- /dev/null
+++ b/internal/feed/v3userinteraction_test.go
@@ -0,0 +1,77 @@
+package feed
+
+import (
+  "encoding/json"
+  "testing"
+)
+
+func TestV3UserInteractionUnmarshalInvalidData(t *testing.T) {
+  test := []byte(`{}`)
+  var val V3UserInteraction
+
+  if err := json.Unmarshal(test, &val); err == nil {
+    t.Errorf("got \"%s\", exp error", val)
+  }
+}
+
+func TestV3UserInteractionUnmarshalUnknown(t *testing.T) {
+  test := []byte(`"foo"`)
+  exp := "unknown CVSS v3 user interaction: foo"
+  var val V3UserInteraction
+
+  err := json.Unmarshal(test, &val)
+  if err == nil {
+    t.Errorf("got \"%s\", exp error", val)
+    return
+  }
+
+  if err.Error() != exp {
+    t.Errorf("got \"%s\", exp \"%s\"", err.Error(), exp)
+  }
+}
+
+func TestV3UserInteractionUnmarshalValid(t *testing.T) {
+  tests := []struct {
+    val string
+    exp V3UserInteraction
+  } {
+    { "\"NONE\"", V3UINone },
+    { "\"REQUIRED\"", V3UIRequired },
+  }
+
+  for _, test := range(tests) {
+    t.Run(test.val, func(t *testing.T) {
+      var got V3UserInteraction
+      if err := json.Unmarshal([]byte(test.val), &got); err != nil {
+        t.Error(err)
+        return
+      }
+
+      if got != test.exp {
+        t.Errorf("got \"%s\", exp \"%s\"", got, test.exp)
+      }
+    })
+  }
+}
+
+func TestV3UserInteractionString(t *testing.T) {
+  tests := []struct {
+    val V3UserInteraction
+    exp string
+  } {
+    { V3UINone, "NONE" },
+    { V3UIRequired, "REQUIRED" },
+
+    { V3UserInteraction(255), "V3UserInteraction(255)" },
+  }
+
+  for _, test := range(tests) {
+    t.Run(test.exp, func(t *testing.T) {
+      got := test.val.String()
+
+      if got != test.exp {
+        t.Errorf("got \"%s\", exp \"%s\"", got, test.exp)
+      }
+    })
+  }
+}