initial commit: @arbiter/core authorization engine with js-rigor hardening

Zanzibar-style authorization graph engine (direct/chain/TTU/defeasible/ binary modes, condensed snapshots, value relations) with 39 rigor test campaigns. Includes fixes for snapshot binary writer/reader format mismatch (snapshot-of-snapshot corruption), possibility write-boundary validation, empty-graph snapshot serialization, relation lookup cache direction collision, config-redefinition cache invalidation, binary threshold semantics, defeasible compiled routing, and comparator reason whitelisting.
2026-07-31 13:44:06 -07:00
commit 717ae1031e
373 changed files with 654131 additions and 0 deletions
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+import { describe, test } from 'node:test';
+import assert from 'node:assert/strict';
+import { Arbiter } from '../../src/core/Arbiter.js';
+
+describe('Reachability edge cases', () => {
+  test('reachability detects path after initialization', () => {
+    const arbiter = new Arbiter();
+    arbiter.addNode('a', 'node');
+    arbiter.addNode('b', 'node');
+    arbiter.addNode('c', 'node');
+    arbiter.addRelation('a', 'links', 'b');
+    arbiter.addRelation('b', 'links', 'c');
+
+    arbiter.graphManager.initializeReachabilityChecker();
+
+    assert.strictEqual(arbiter.isReachable('a', 'c'), true);
+    assert.strictEqual(arbiter.isReachable('c', 'a'), false);
+  });
+
+  test('reachability returns false for missing nodes', () => {
+    const arbiter = new Arbiter();
+    arbiter.addNode('a', 'node');
+    arbiter.graphManager.initializeReachabilityChecker();
+    assert.strictEqual(arbiter.isReachable('a', 'missing'), false);
+  });
+
+  test('backward reachability checks reverse direction', () => {
+    const arbiter = new Arbiter();
+    arbiter.addNode('a', 'node');
+    arbiter.addNode('b', 'node');
+    arbiter.addRelation('a', 'links', 'b');
+
+    arbiter.graphManager.initializeReachabilityChecker({ enableBackwardIndex: true });
+
+    const srcId = arbiter.nodeIdByKey.get('b');
+    const dstId = arbiter.nodeIdByKey.get('a');
+    const backwardReachable = arbiter.reachabilityChecker.isReachable(srcId, dstId, { direction: 'backward' });
+
+    assert.strictEqual(backwardReachable, true);
+  });
+});