Remove deep cloning of contexts during parsing

This improves overall parsing performance

Author: jeswr

lib/ParsingContext.ts

@@ -207,7 +207,7 @@ export class ParsingContext {
           || scopedContext[key]['@context']['@propagate']; // Propagation is true by default
 
         if (propagate !== false || i === keysOriginal.length - 1 - offset) {
-          contextRaw = scopedContext;
+          contextRaw = { ...scopedContext };
 
           // Clean up final context
           delete contextRaw['@propagate'];

lib/entryhandler/keyword/EntryHandlerKeywordType.ts

@@ -69,15 +69,11 @@ export class EntryHandlerKeywordType extends EntryHandlerKeyword {
     if (hasTypedScopedContext) {
       // Do not propagate by default
       scopedContext = scopedContext.then((c) => {
-        if (!('@propagate' in c.getContextRaw())) {
-          c.getContextRaw()['@propagate'] = false;
-        }
-
         // Set the original context at this depth as a fallback
         // This is needed when a context was already defined at the given depth,
         // and this context needs to remain accessible from child nodes when propagation is disabled.
-        if (c.getContextRaw()['@propagate'] === false) {
-          c.getContextRaw()['@__propagateFallback'] = context.getContextRaw();
+        if (c.getContextRaw()['@propagate'] !== true) {
+          return new JsonLdContextNormalized({ ...c.getContextRaw(), '@propagate': false, '@__propagateFallback': context.getContextRaw() });
         }
 
         return c;

package.json

@@ -38,7 +38,7 @@
     "buffer": "^6.0.3",
     "canonicalize": "^1.0.1",
     "http-link-header": "^1.0.2",
-    "jsonld-context-parser": "^2.3.3",
+    "jsonld-context-parser": "^2.4.0",
     "rdf-data-factory": "^1.1.0",
     "readable-stream": "^4.0.0"
   },

test/ParsingContext-test.ts

@@ -1,4 +1,4 @@
-import {JsonLdContextNormalized} from "jsonld-context-parser";
+import {JsonLdContextNormalized, ContextParser} from "jsonld-context-parser";
 import {ParsingContext} from "../lib/ParsingContext";
 import {ParsingContextMocked} from "../mocks/ParsingContextMocked";
 
@@ -607,22 +607,20 @@ describe('ParsingContext', () => {
       describe('for type-scoped and property-scoped contexts', () => {
 
         beforeEach(() => {
-          parsingContext.contextTree.setContext(['', 'a'], Promise.resolve(new JsonLdContextNormalized({
-            '@__propagateFallback': { fallback: true },
-            '@propagate': false,
+          const contextParser = new ContextParser();
+          parsingContext.contextTree.setContext(['', 'a'], contextParser.parse({
             '@vocab': 'http://bla.org/',
             'bar': {
               '@context': {
                 baz: { '@type': '@vocab' },
               },
             },
-          })));
+          }));
         });
 
         it('should consider the applicable property-scoped context', async () => {
           return expect(await parsingContext.getContext(['', 'a', 'bar'], 0))
             .toEqual(new JsonLdContextNormalized({
-              '@__propagateFallback': { fallback: true },
               '@vocab': 'http://bla.org/',
               'bar': { '@id': 'http://bla.org/bar' },
               'baz': { '@type': '@vocab', '@id': 'http://bla.org/baz' },

yarn.lock

@@ -2518,14 +2518,13 @@ jsonld-context-parser@^2.0.2, jsonld-context-parser@^2.1.3:
     http-link-header "^1.0.2"
     relative-to-absolute-iri "^1.0.5"
 
-jsonld-context-parser@^2.3.3:
-  version "2.3.3"
-  resolved "https://registry.yarnpkg.com/jsonld-context-parser/-/jsonld-context-parser-2.3.3.tgz#0bdab9eb5cb4b7e68aa7d6c38e58455363caaf9c"
-  integrity sha512-H+REInOx7XI2ciF8wJV31D20Bh+ofBmEjN2Tkds51vypqDJIiD341E5g+hYyrEInIKRnbW58TN/Ehz+ACT0l0w==
+jsonld-context-parser@^2.4.0:
+  version "2.4.0"
+  resolved "https://registry.yarnpkg.com/jsonld-context-parser/-/jsonld-context-parser-2.4.0.tgz#fae15a56c5ceabd1c4520ab1a9cc12c9a0a8b67d"
+  integrity sha512-ZYOfvh525SdPd9ReYY58dxB3E2RUEU4DJ6ZibO8AitcowPeBH4L5rCAitE2om5G1P+HMEgYEYEr4EZKbVN4tpA==
   dependencies:
     "@types/http-link-header" "^1.0.1"
     "@types/node" "^18.0.0"
-    canonicalize "^1.0.1"
     cross-fetch "^3.0.6"
     http-link-header "^1.0.2"
     relative-to-absolute-iri "^1.0.5"