Honor json:"-" on embedded fields during initial field walk

docparse/docparse_test.go

@@ -565,6 +565,39 @@ func TestGetReference(t *testing.T) {
 	}
 }
 
+// Regression: an embedded qualified pointer type tagged json:"-" (for
+// example *mail.Address with a json:"-" tag) previously caused a
+// nil-pointer panic because the first field-walk pass tried to resolve
+// the embed before checking the tag. The fix is to honor json:"-" in
+// that pass too. We also verify the embed is absent from the resulting
+// Reference.Fields and the referenced external type is not pulled into
+// prog.References.
+func TestGetReference_EmbedJSONDash(t *testing.T) {
+	prog := NewProgram(false)
+	prog.Config.StructTag = "json"
+	out, err := GetReference(prog, "req", false, "testEmbedJSONDash", ".")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if out == nil {
+		t.Fatal("nil reference")
+	}
+
+	var names []string
+	for _, f := range out.Fields {
+		names = append(names, f.Name)
+	}
+	wantFields := []string{"ID"}
+	if !reflect.DeepEqual(names, wantFields) {
+		t.Errorf("fields: got %v, want %v", names, wantFields)
+	}
+
+	if _, ok := prog.References["mail.Address"]; ok {
+		t.Errorf("mail.Address was resolved despite json:\"-\" on embed")
+	}
+}
+
 func TestParseResponse(t *testing.T) {
 	tests := []struct {
 		in       string

docparse/find.go

@@ -438,6 +438,15 @@ func GetReference(prog *Program, context string, isEmbed bool, lookup, filePath
 				continue
 			}
 
+			// Skip embedded fields explicitly excluded from the schema
+			// (e.g. `json:"-"`). The nested-walk loop below applies the
+			// same skip; doing it here too avoids resolving a type we
+			// will not emit, which matters for embeds whose underlying
+			// type would otherwise pull in a large external graph.
+			if goutil.TagName(f, tagName) == "-" {
+				continue
+			}
+
 			switch t := f.Type.(type) {
 			case *ast.Ident:
 				err = resolveType(prog, context, false, t, "", pkg)

docparse/test.go

@@ -1,5 +1,7 @@
 package docparse
 
+import "net/mail"
+
 // For tests. We don't parse test files.
 
 // testObject general documentation.
@@ -16,3 +18,15 @@ type testObject struct {
 
 	Bar []string
 }
+
+// testEmbedJSONDash covers the case where a struct embeds a qualified
+// pointer type purely for Go-level method promotion and excludes it from
+// the schema with `json:"-"`. The embed must not be resolved.
+//
+//nolint:unused
+type testEmbedJSONDash struct {
+	*mail.Address `json:"-"`
+
+	// ID documentation {required}.
+	ID int
+}