feat(core): introduce decoupled ContextManager and Sidecar architecture

2026-07-12 02:50:41 -07:00 · 2026-04-06 16:43:04 +00:00
parent 15298b28c2
commit ac6dc1d477
31 changed files with 3811 additions and 0 deletions
@@ -0,0 +1,113 @@
+import { IrMapper } from './ir/mapper.js';
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect } from 'vitest';
+import {
+  createMockContextConfig,
+  setupContextComponentTest,
+} from './testing/contextTestUtils.js';
+
+describe('ContextManager Barrier Tests', () => {
+  it('Soft Barrier (retainedTokens): should inject ready variants and shrink projection', async () => {
+    const config = createMockContextConfig();
+    const { chatHistory, contextManager } = setupContextComponentTest(config);
+
+    // 1. Shrink limits: 1 char = 1 token. RetainedTokens = 10. MaxTokens = 100.
+    IrMapper.setConfig({ charsPerToken: 1 });
+
+    contextManager['sidecar'].budget.retainedTokens = 5;
+    contextManager['sidecar'].budget.maxTokens = 100;
+
+    // 2. Build tiny history: 5 turns (10 messages). 2 tokens per turn.
+    const tinyHistory = [];
+    for (let i = 0; i < 5; i++) {
+      tinyHistory.push({ role: 'user', parts: [{ text: `U${i}` }] });
+      tinyHistory.push({ role: 'model', parts: [{ text: `M${i}` }] });
+    }
+
+    // Set history directly to avoid event races
+    await chatHistory.set(tinyHistory);
+
+    // 3. Pre-verify baseline length.
+    const baseline = await contextManager.projectCompressedHistory();
+    expect(baseline.length).toBe(10);
+
+    // 4. Emit a fake snapshot covering the first 3 pairs (6 messages)
+    const targetEp = contextManager['pristineEpisodes'][2];
+    const replacedIds = contextManager['pristineEpisodes']
+      .slice(0, 3)
+      .map((ep) => ep.id);
+
+    contextManager['eventBus'].emitVariantReady({
+      targetId: targetEp.id,
+      variantId: 'snapshot',
+      variant: {
+        status: 'ready',
+        type: 'snapshot',
+        replacedEpisodeIds: replacedIds,
+        episode: {
+          id: 'snapshot-ep',
+          timestamp: Date.now(),
+          trigger: {
+            id: 't1',
+            type: 'USER_PROMPT',
+            semanticParts: [],
+            metadata: {
+              originalTokens: 0,
+              currentTokens: 0,
+              transformations: [],
+            },
+          },
+          yield: {
+            id: 'y1',
+            type: 'AGENT_YIELD',
+            text: '<SNAP>',
+            metadata: {
+              originalTokens: 5,
+              currentTokens: 5,
+              transformations: [],
+            },
+          },
+          steps: [],
+        },
+      },
+    });
+
+    // 5. Verify Projection shrinks: 6 original messages replaced by 1 snapshot episode (1 text part) -> length 5.
+    const projection = await contextManager.projectCompressedHistory();
+    expect(projection.length).toBe(5);
+    // console.dir(projection, {depth: null});
+    // projection[0] should be the snapshot yield
+    expect(projection[0].parts![0].text).toBe('<SNAP>');
+  });
+
+  it('Hard Barrier (maxTokens): should ruthlessly truncate unprotected episodes', async () => {
+    const config = createMockContextConfig();
+    const { chatHistory, contextManager } = setupContextComponentTest(config);
+
+    // 1. Shrink limits: maxTokens = 15.
+    IrMapper.setConfig({ charsPerToken: 1 });
+    contextManager['sidecar'].budget.maxTokens = 15;
+
+    // 2. Build history: 2 turns. Total = 24 tokens.
+    const history = [
+      { role: 'user', parts: [{ text: 'U0' }] },
+      { role: 'model', parts: [{ text: 'M0_LARGE!!' }] },
+      { role: 'user', parts: [{ text: 'U1' }] },
+      { role: 'model', parts: [{ text: 'M1_LARGE!!' }] },
+    ];
+    await chatHistory.set(history);
+
+    const projection = await contextManager.projectCompressedHistory();
+
+    // Because Turn 0 is architecturally protected (system prompt/initialization), it SURVIVES!
+    // Turn 1 is dropped to satisfy the maxTokens constraint.
+    expect(projection.length).toBe(2);
+    expect(projection[0].parts![0].text).toBe('U0');
+    expect(projection[1].parts![0].text).toBe('M0_LARGE!!');
+  });
+});