1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
import { describe, expect, it } from "vitest";
import {
buildCompactionPrompt,
buildCompactionRequest,
buildSummaryTurnText,
DEFAULT_TAIL_TURNS,
extractPreviousSummary,
renderTranscript,
SUMMARY_MARKER,
SUMMARY_TEMPLATE,
selectHeadTail,
} from "../../src/compaction/index.js";
import type { ChatMessage } from "../../src/types/index.js";
function user(text: string): ChatMessage {
return { role: "user", chunks: [{ type: "text", text }] };
}
function assistant(text: string): ChatMessage {
return { role: "assistant", chunks: [{ type: "text", text }] };
}
describe("selectHeadTail", () => {
it("returns empty head when turns <= tailTurns (nothing to compact)", () => {
const msgs = [user("u1"), assistant("a1"), user("u2"), assistant("a2")];
const { head, tail } = selectHeadTail(msgs, 2);
expect(head).toEqual([]);
expect(tail).toEqual(msgs);
});
it("keeps the last N turns verbatim and summarizes the rest", () => {
const msgs = [
user("u1"),
assistant("a1"),
user("u2"),
assistant("a2"),
user("u3"),
assistant("a3"),
];
const { head, tail } = selectHeadTail(msgs, 2);
expect(tail[0]).toBe(msgs[2]);
expect(tail.at(-1)).toBe(msgs[5]);
expect(head).toEqual([msgs[0], msgs[1]]);
});
it("a turn includes trailing assistant/tool messages up to the next user", () => {
const msgs = [user("u1"), assistant("a1a"), assistant("a1b"), user("u2"), assistant("a2")];
const { head, tail } = selectHeadTail(msgs, 1);
expect(head).toEqual([msgs[0], msgs[1], msgs[2]]);
expect(tail).toEqual([msgs[3], msgs[4]]);
});
it("tailTurns<=0 → everything is head", () => {
const msgs = [user("u1"), assistant("a1")];
expect(selectHeadTail(msgs, 0)).toEqual({ head: msgs, tail: [] });
});
it("defaults to DEFAULT_TAIL_TURNS", () => {
const msgs = [user("u1"), user("u2"), user("u3")];
const def = selectHeadTail(msgs);
const explicit = selectHeadTail(msgs, DEFAULT_TAIL_TURNS);
expect(def).toEqual(explicit);
});
});
describe("buildCompactionPrompt", () => {
it("creates a fresh-summary instruction without a previous summary", () => {
const p = buildCompactionPrompt({});
expect(p).toContain("Create a new anchored summary");
expect(p).toContain(SUMMARY_TEMPLATE);
expect(p).not.toContain("<previous-summary>");
});
it("anchors on a previous summary when provided", () => {
const p = buildCompactionPrompt({ previousSummary: "## Goal\n- old" });
expect(p).toContain("Update the anchored summary");
expect(p).toContain("<previous-summary>");
expect(p).toContain("## Goal\n- old");
expect(p).toContain(SUMMARY_TEMPLATE);
});
});
describe("extractPreviousSummary", () => {
it("returns undefined when the first user message is not a seeded summary", () => {
expect(extractPreviousSummary([user("hello"), assistant("hi")])).toBeUndefined();
});
it("extracts the body of a seeded summary turn (marker stripped)", () => {
const seeded = user(buildSummaryTurnText("## Goal\n- build X"));
expect(extractPreviousSummary([seeded, assistant("ok")])).toBe("## Goal\n- build X");
});
});
describe("renderTranscript", () => {
it("renders user/assistant text blocks", () => {
const t = renderTranscript([user("hello"), assistant("hi there")]);
expect(t).toContain("## User\nhello");
expect(t).toContain("## Assistant\nhi there");
});
it("renders tool calls and caps long tool results", () => {
const big = "x".repeat(5000);
const msg: ChatMessage = {
role: "assistant",
chunks: [
{
type: "tool-batch",
calls: [{ id: "c1", name: "read_file", arguments: { path: "a" }, result: big }],
},
],
};
const t = renderTranscript([msg], 2000);
expect(t).toContain('[tool read_file {"path":"a"}]');
expect(t).toContain("chars truncated for summary");
expect(t.length).toBeLessThan(5000 + 200);
});
it("skips a seeded prior-summary user turn", () => {
const seeded = user(buildSummaryTurnText("## Goal\n- prior"));
const t = renderTranscript([seeded, assistant("work")]);
expect(t).not.toContain("prior");
expect(t).toContain("## Assistant\nwork");
});
it("omits thinking/error/system chunks", () => {
const msg: ChatMessage = {
role: "assistant",
chunks: [
{ type: "thinking", text: "secret reasoning" },
{ type: "text", text: "visible" },
{ type: "error", message: "boom" },
],
};
const t = renderTranscript([msg]);
expect(t).toContain("visible");
expect(t).not.toContain("secret reasoning");
expect(t).not.toContain("boom");
});
});
describe("buildCompactionRequest", () => {
it("returns no prompt when there is nothing to compact", () => {
const msgs = [user("u1"), assistant("a1")];
const req = buildCompactionRequest({ messages: msgs, tailTurns: 2 });
expect(req.prompt).toBeUndefined();
expect(req.head).toEqual([]);
expect(req.tail).toEqual(msgs);
});
it("builds a prompt with transcript + instruction and exposes head/tail", () => {
const msgs = [
user("first task"),
assistant("did stuff"),
user("second"),
assistant("more"),
user("third"),
assistant("done"),
];
const req = buildCompactionRequest({ messages: msgs, tailTurns: 2 });
expect(req.prompt).toBeDefined();
expect(req.prompt).toContain("first task");
expect(req.prompt).toContain("Create a new anchored summary");
expect(req.tail[0]).toBe(msgs[2]);
expect(req.head[0]).toBe(msgs[0]);
});
it("anchors on a prior seeded summary", () => {
const msgs = [
user(buildSummaryTurnText("## Goal\n- old goal")),
assistant("ack"),
user("new work"),
assistant("did new"),
user("more work"),
assistant("did more"),
];
const req = buildCompactionRequest({ messages: msgs, tailTurns: 2 });
expect(req.previousSummary).toBe("## Goal\n- old goal");
expect(req.prompt).toContain("Update the anchored summary");
// head = [seeded-summary, "ack"]; seeded summary is skipped in the
// transcript, so "ack" represents the summarized head. "new work" lives
// in the preserved tail (last 2 turns), not the summary body.
expect(req.prompt).toContain("ack");
expect(
req.tail.some((m) => m.chunks.some((c) => c.type === "text" && c.text === "new work")),
).toBe(true);
});
});
describe("buildSummaryTurnText", () => {
it("prefixes the marker so a later compaction can anchor", () => {
const seeded = buildSummaryTurnText("## Goal\n- x");
expect(seeded.startsWith(SUMMARY_MARKER)).toBe(true);
expect(extractPreviousSummary([user(seeded)])).toBe("## Goal\n- x");
});
});
|
