fix(jsonschema): Handle empty url fragment "#", add unit tests.

schema.go

@@ -12,7 +12,6 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
-	"strings"
 
 	"github.com/qri-io/jsonpointer"
 )
@@ -91,13 +90,13 @@ func (rs *RootSchema) UnmarshalJSON(data []byte) error {
 				ids[sch.ID] = sch
 				// For the record, I think this is ridiculous.
 				if u, err := url.Parse(sch.ID); err == nil {
-					// This is if the identifier is defined as a reference (with #)
-					// i.e. #/properties/firstName
-					// in this case, u.Fragment will have /properties/firstName
-					if strings.HasPrefix(sch.ID, "#") {
-						ids[u.Fragment[1:]] = sch
-					} else {
+					if len(u.Path) >= 1 {
 						ids[u.Path[1:]] = sch
+					} else if len(u.Fragment) >= 1 {
+						// This handles if the identifier is defined as only a fragment (with #)
+						// i.e. #/properties/firstName
+						// in this case, u.Fragment will have /properties/firstName
+						ids[u.Fragment[1:]] = sch
 					}
 				}
 			}

schema_test.go

@@ -125,6 +125,41 @@ func TestTopLevelType(t *testing.T) {
 	}
 }
 
+func TestParseUrl(t *testing.T) {
+	// Easy case, id is a standard URL
+	schemaObject := []byte(`{
+    "title": "Car",
+    "type": "object",
+    "$id": "http://example.com/root.json"
+}`)
+	rs := &RootSchema{}
+	if err := json.Unmarshal(schemaObject, rs); err != nil {
+		panic("unmarshal schema: " + err.Error())
+	}
+
+	// Tricky case, id is only a URL fragment
+	schemaObject = []byte(`{
+    "title": "Car",
+    "type": "object",
+    "$id": "#/properites/firstName"
+}`)
+	rs = &RootSchema{}
+	if err := json.Unmarshal(schemaObject, rs); err != nil {
+		panic("unmarshal schema: " + err.Error())
+	}
+
+	// Another tricky case, id is only an empty fragment
+	schemaObject = []byte(`{
+    "title": "Car",
+    "type": "object",
+    "$id": "#"
+}`)
+	rs = &RootSchema{}
+	if err := json.Unmarshal(schemaObject, rs); err != nil {
+		panic("unmarshal schema: " + err.Error())
+	}
+}
+
 func TestMust(t *testing.T) {
 	defer func() {
 		if r := recover(); r != nil {