From 7c0a26946e59b519e108273246718082a4c72fff Mon Sep 17 00:00:00 2001
From: "David I. Lehn" <dlehn@digitalbazaar.com>
Date: Thu, 27 Feb 2020 12:24:23 -0500
Subject: [PATCH] Handle term definition on `@type` with empty map.

---
 CHANGELOG.md   | 1 +
 lib/context.js | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 769d2466..1a1b5e2e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 - Terms of the form of a relative IRI may not be used as prefixes.
 - Match spec error code "invalid context entry" vs "invalid context member".
 - Keywords may not be used as prefixes.
+- Handle term definition on `@type` with empty map.
 
 ### Changed
 - Keep term definitions mapping to null so they may be protected.
diff --git a/lib/context.js b/lib/context.js
index 30077d9a..09d903f0 100644
--- a/lib/context.js
+++ b/lib/context.js
@@ -411,7 +411,8 @@ api.createTermDefinition = ({
      api.processingMode(activeCtx, 1.1)) {
 
     const validKeys = ['@container', '@id', '@protected'];
-    if(Object.keys(value).some(k => !validKeys.includes(k))) {
+    const keys = Object.keys(value);
+    if(keys.length === 0 || keys.some(k => !validKeys.includes(k))) {
       throw new JsonLdError(
         'Invalid JSON-LD syntax; keywords cannot be overridden.',
         'jsonld.SyntaxError',