Files
hermes-webui/tests/test_issue4970_stream_done_shrink_regression.py
T
37547a7bd1 Release exp-v0.52.171: keep settled Worklog in place across stream settlement (#6454) (#6837)
* test: prove worklog continuity across stream settle

* fix: keep settled worklog in place on stream done

* fix: preserve settle follow ordering

* test: wire settled worklog frame proof

* fix: preserve settled worklog detail disclosure

* fix: preserve default-open settled worklogs

* fix: preserve blank-owner worklogs

* fix: keep render fallback self-contained

* ci: retrigger hosted checks

* style(worklog): grow collapsed Worklog rail tap target to 44px on touch devices (#6454 follow-up)

* Release exp-v0.52.171: keep settled Worklog in place across stream settlement (#6454)

---------

Co-authored-by: Frank Song <franksong2702@gmail.com>
Co-authored-by: nesquena-hermes <nesquena-hermes@users.noreply.github.com>
2026-08-07 18:06:57 -07:00

556 lines
28 KiB
Python

"""Regression locks for #4970 round 6: stream-end worklog collapse shrink jump.
Round 7 (scoping fix): the keep-open exception must apply to ONLY the turn that
just settled, gated on a one-shot stream-id token, NOT to every historical
settled worklog on every re-render.
Round 8 (mobile unpinned fix, #MOBILESCROLL follow-up): the keep-open exception
must also cover the UNPINNED reader who scrolled up to read inside the
just-settled turn. The earlier round scoped keep-open to pinned followers only,
on the assumption that unpinned readers "preserve their viewport normally". That
holds on desktop (overflow-anchor:none + JS snapshot restore) but NOT on mobile:
the CSS resting value is overflow-anchor:auto and _fixMobileScrollJank() flips an
inline overflow-anchor:none over the settle render, so native anchoring is
suppressed during the one frame the unpinned reader needs it to absorb the
above-viewport worklog shrink — the content leaps to the top of the turn (the
"往回大跳" report). Keeping the just-settled worklog open removes the shrink for
every device/anchor-mode, so the helper now returns true for the armed turn
regardless of pin state.
These tests are BEHAVIORAL: they extract the real
`_shouldKeepSettledWorklogOpenForStreamSettle` helper plus its arm/disarm token
API from static/ui.js and execute them in Node, then drive two settled turns and
assert the second (historical) turn collapses while the just-settled one stays
open for both pin states.
"""
import json
import shutil
import subprocess
import textwrap
from pathlib import Path
import pytest
ROOT = Path(__file__).resolve().parent.parent
UI_JS = (ROOT / "static" / "ui.js").read_text(encoding="utf-8")
MESSAGES_JS = (ROOT / "static" / "messages.js").read_text(encoding="utf-8")
def _function_body(src: str, name: str) -> str:
marker = f"function {name}"
start = src.index(marker)
brace = src.index("{", start)
depth = 0
for idx in range(brace, len(src)):
ch = src[idx]
if ch == "{":
depth += 1
elif ch == "}":
depth -= 1
if depth == 0:
return src[brace + 1 : idx]
raise AssertionError(f"function {name} body not found")
def _extract(name: str) -> str:
"""Return the full `function name(...){...}` text from ui.js."""
marker = f"function {name}"
start = UI_JS.index(marker)
body = _function_body(UI_JS, name)
sig = UI_JS[start : UI_JS.index("{", start)]
return f"{sig}{{{body}}}"
def test_helper_and_token_threaded_through_render():
# Structural: the helper takes a streamId and gates on the one-shot token,
# and the call site threads the message's stream id (not a no-arg call).
helper = _function_body(UI_JS, "_shouldKeepSettledWorklogOpenForStreamSettle")
assert "_keepSettledWorklogOpenForStreamId" in helper
# Round 8: the helper must NOT re-narrow to pinned-only — keep-open now covers
# the unpinned reader too, so the pin-state gate is gone from the return.
assert "_scrollPinned" not in helper, (
"keep-open must apply to the just-settled turn regardless of pin state "
"(unpinned mobile readers also get the shrink jump); do not gate on "
"_scrollPinned/_messageUserUnpinned."
)
render_fn = _function_body(UI_JS, "_renderSettledAnchorSceneForMessage")
assert "_shouldKeepSettledWorklogOpenForStreamSettle(streamId)" in render_fn
# keepSettledWorklogOpen must still drive the settled-render collapsed flag.
# #5941 OR'd in an errored-turn keep-open term, so the expression is now
# `collapsed:!(keepSettledWorklogOpen||erroredWorklogKeepOpen)` — assert the
# invariant (keepSettledWorklogOpen negates into `collapsed`) without pinning
# the exact term list.
assert "collapsed:!(keepSettledWorklogOpen" in render_fn
group_fn = _function_body(UI_JS, "_anchorSceneWorklogGroup")
assert "collapsed:(opts&&opts.collapsed!==undefined)?opts.collapsed:!live" in group_fn
# The STREAM_DONE handler arms one-shot then disarms around the render.
assert "_armKeepSettledWorklogOpen(_settledStreamId)" in MESSAGES_JS
assert "_disarmKeepSettledWorklogOpen()" in MESSAGES_JS
@pytest.mark.skipif(shutil.which("node") is None, reason="node required for behavioral test")
def test_just_settled_turn_stays_open_for_both_pin_states_history_collapses():
"""Only the just-settled turn stays open; it does so for pinned AND unpinned."""
helper = _extract("_shouldKeepSettledWorklogOpenForStreamSettle")
arm = _extract("_armKeepSettledWorklogOpen")
disarm = _extract("_disarmKeepSettledWorklogOpen")
harness = textwrap.dedent(f"""
let _keepSettledWorklogOpenForStreamId=null;
let _scrollPinned=true, _messageUserUnpinned=false; // pinned follower
{helper}
{arm}
{disarm}
const out={{}};
// Turn A just settled: arm A, render A (open), render historical B (collapsed), disarm.
_armKeepSettledWorklogOpen('streamA');
out.A_open_pinned = _shouldKeepSettledWorklogOpenForStreamSettle('streamA'); // expect true
out.B_history = _shouldKeepSettledWorklogOpenForStreamSettle('streamB'); // expect false
// Round 8: an UNPINNED reader of the just-settled turn must ALSO keep it open
// (the mobile above-viewport shrink jump). This is the behavior change.
_messageUserUnpinned=true; _scrollPinned=false;
out.A_open_unpinned = _shouldKeepSettledWorklogOpenForStreamSettle('streamA'); // expect true
out.B_history_unpinned = _shouldKeepSettledWorklogOpenForStreamSettle('streamB'); // expect false
_disarmKeepSettledWorklogOpen();
// After disarm, even A collapses on a later re-render (one-shot scope intact).
out.A_after_disarm = _shouldKeepSettledWorklogOpenForStreamSettle('streamA'); // false
// No token at all → never keep open.
out.no_token = _shouldKeepSettledWorklogOpenForStreamSettle(''); // false
console.log(JSON.stringify(out));
""")
res = subprocess.run(["node", "-e", harness], capture_output=True, text=True, timeout=30)
assert res.returncode == 0, res.stderr
out = json.loads(res.stdout.strip())
assert out["A_open_pinned"] is True, "just-settled turn must keep worklog open for pinned follower"
assert out["A_open_unpinned"] is True, (
"just-settled turn must ALSO keep worklog open for an unpinned reader — "
"the above-viewport collapse shrink janks them to the turn top on mobile"
)
assert out["B_history"] is False, "historical settled worklog must stay collapsed (pinned)"
assert out["B_history_unpinned"] is False, "historical settled worklog must stay collapsed (unpinned)"
assert out["A_after_disarm"] is False, "exception must be one-shot, cleared after the render"
assert out["no_token"] is False, "no armed stream id → never keep open"
def test_forced_open_dom_is_not_cached_while_token_armed():
# Round 9 (#5260 gate-cert, RED): the keep-open settle render force-opens the
# worklog; that DOM must NOT be written into _sessionHtmlCache while the token
# is armed, or it persists the forced-open worklog across session switches /
# restores and silently overrides a user-collapsed worklog.
armed = _function_body(UI_JS, "_isKeepSettledWorklogOpenArmed")
assert "_keepSettledWorklogOpenForStreamId!==null" in armed, (
"_isKeepSettledWorklogOpenArmed() must report whether the one-shot "
"keep-open token is currently armed."
)
# The cache-write guard in renderMessages must consult the armed check (via a
# typeof-safe local) so the forced-open settle render is excluded from
# _sessionHtmlCache.set().
assert "typeof _isKeepSettledWorklogOpenArmed==='function'" in UI_JS, (
"the cache guard must call _isKeepSettledWorklogOpenArmed() through a "
"typeof check so standalone renderMessages() harnesses still work (#5260)."
)
assert "!_keepOpenArmed" in UI_JS, (
"the _sessionHtmlCache population guard must include !_keepOpenArmed so the "
"forced-open settle render DOM is not cached (#5260)."
)
# Anchor it to the actual cache-write site: the armed check sits on the same
# condition as the INFLIGHT / transient-UI guards that gate the cache .set().
cache_guard_idx = UI_JS.index("!_keepOpenArmed")
window = UI_JS[cache_guard_idx : cache_guard_idx + 400]
assert "_sessionHtmlCache.set(" in window, (
"the !_keepOpenArmed guard must gate the "
"_sessionHtmlCache.set() call, not some unrelated branch."
)
def test_stream_done_collapses_in_place_after_disarm_with_render_fallback():
# Round 9 (#5260 gate-cert, RED x2): disarming the token alone leaves the
# forced-open worklog on screen. The first re-push collapse-rendered only the
# NON-following path and let a pinned follower fall through to scrollToBottom()
# — but scrollToBottom() does NOT re-render (ui.js), so the armed-open DOM
# persisted for pinned followers. Fix: run the scroll-PRESERVING collapse pass
# UNCONDITIONALLY right after disarm (covers both pin states), THEN scrollToBottom()
# only for followers to re-settle at the tail. This makes keep-open genuinely
# one-frame for everyone.
#
# Round 10 (#6385): capture the scroll snapshot from the LIVE DOM before arming
# keep-open, so the collapse render below anchors to the content the reader was
# actually viewing — not to a stale intermediate state where the worklog was
# temporarily expanded. The pre-capture variable must be defined before arm and
# threaded into the collapse pass as `_prescrollSnapshot`.
pre_capture_idx = MESSAGES_JS.index("_doneLiveScrollSnapshot")
arm_idx = MESSAGES_JS.index("_armKeepSettledWorklogOpen")
assert pre_capture_idx < arm_idx, (
"_doneLiveScrollSnapshot must be captured before _armKeepSettledWorklogOpen "
"to snapshot the live (not expanded-worklog) DOM positions."
)
disarm_idx = MESSAGES_JS.index("_disarmKeepSettledWorklogOpen()")
after = MESSAGES_JS[disarm_idx : disarm_idx + 1100]
# #6414: the preferred collapse is now in-place. The old second full
# transcript render remains only as a fail-closed fallback when the exact
# settled Worklog cannot be identified or collapsed.
assert "_collapseJustSettledWorklogInPlace" in after
assert "&& _collapseJustSettledWorklogInPlace(_settledStreamId)" in after, (
"after _disarmKeepSettledWorklogOpen() the STREAM_DONE handler must first "
"collapse the just-settled Worklog in place, avoiding a second transcript "
"rebuild that removes the freshly-settled DOM."
)
assert "_restoreMessageScrollSnapshotSameFrame(_doneLiveScrollSnapshot)" in after, (
"the in-place collapse path must still restore the pre-captured live scroll "
"snapshot so pinned and unpinned readers keep their viewport."
)
assert "_renderMessagesWithScrollSnapshot({_prescrollSnapshot:_doneLiveScrollSnapshot})" in after, (
"if in-place collapse cannot prove it owns the exact settled Worklog, the "
"STREAM_DONE handler must fall back to the old scroll-preserving render pass."
)
# The follower re-settle (scrollToBottom) must come AFTER the collapse/fallback
# handling; otherwise a pinned follower can keep the forced-open DOM
# (scrollToBottom does not re-render).
collapse_pos = after.index("_collapseJustSettledWorklogInPlace")
fallback_pos = after.index("_renderMessagesWithScrollSnapshot")
follow_pos = after.index("shouldFollowOnDone")
assert collapse_pos < follow_pos, (
"the in-place collapse must run BEFORE the shouldFollowOnDone scrollToBottom() "
"so BOTH pinned and unpinned readers get the worklog collapsed; scrollToBottom() "
"alone does not re-render and would leave a pinned follower forced-open."
)
assert fallback_pos < follow_pos, (
"the fallback render pass must also stay before shouldFollowOnDone so the "
"fail-closed path preserves the prior #5260 invariant."
)
assert "scrollToBottom()" in after, (
"a pinned/near-bottom follower must scrollToBottom() after the collapse "
"handling to re-settle exactly at the tail."
)
# And the wrapper must exist and be scroll-preserving (capture → render →
# restore same-frame), so the collapse height change is absorbed by the JS
# restore rather than left to native scroll-anchoring (suppressed on mobile).
wrapper = _function_body(UI_JS, "_renderMessagesWithScrollSnapshot")
assert "_captureMessageScrollSnapshot()" in wrapper
assert "_restoreMessageScrollSnapshotSameFrame" in wrapper
def test_in_place_settled_worklog_collapse_defers_rows_without_full_rebuild():
body = _function_body(UI_JS, "_collapseJustSettledWorklogInPlace")
assert "_assistantTurnHasVisibleRenderedSegment(ownerTurn)" in body
assert "if(ownerHasVisibleSegment===null) return false" in body
assert "const keepOpen=!ownerHasVisibleSegment" in body
assert "[data-anchor-settled-scene-owner=\"1\"]" in body
assert "data-anchor-stream-id" in body
assert "_deferredWorklogRowsFromGroup(group)" in body
assert "_captureWorklogDetailDisclosureState(group)" in body
assert "_worklogDetailsExpandedDefault()&&savedDisclosure!=='closed'" in body
assert "group._deferredWorklogRows=rows" in body
assert "group._deferredWorklogDisclosure=detailDisclosure&&detailDisclosure.size" in body
assert "data-worklog-rows-deferred" in body
assert "tool-call-group-collapsed" in body
assert "_syncToolCallGroupSummary(group)" in body
assert "requestAnimationFrame" in body
assert "list.replaceChildren()" in body
assert "renderMessages(" not in body
@pytest.mark.skipif(shutil.which("node") is None, reason="node required for behavioral test")
def test_done_defers_live_dom_removal_but_other_terminal_paths_still_clear():
"""The normal done handoff must not expose an empty live-worklog frame.
The settled transcript render owns replacement of the live DOM. Calling the
shared cleanup helper in preserve-DOM mode may stop timers and reset intent,
but must leave the visible rows in place until that replacement occurs.
Default cleanup remains destructive for error/cancel paths.
"""
clear_live = _extract("clearLiveToolCards")
done_start = MESSAGES_JS.index("source.addEventListener('done',e=>{")
done = MESSAGES_JS[done_start : done_start + 14000]
harness = textwrap.dedent(f"""
let removed = 0;
let timerClears = 0;
let intentClears = 0;
const rows = [{{remove() {{ removed++; }}}}, {{remove() {{ removed++; }}}}];
const inner = {{querySelectorAll() {{ return rows; }}}};
const legacy = {{innerHTML: 'legacy', style: {{display: ''}}}};
globalThis._clearActivityElapsedTimer = () => {{ timerClears++; }};
globalThis._clearLiveActivityUserIntent = () => {{ intentClears++; }};
globalThis._assistantTurnBlocks = () => inner;
globalThis.$ = (id) => id === 'liveAssistantTurn' ? {{}} : id === 'liveToolCards' ? legacy : null;
{clear_live}
clearLiveToolCards({{preserveDom: true}});
const preserved = {{removed, timerClears, intentClears, legacy: legacy.innerHTML, legacyDisplay: legacy.style.display}};
clearLiveToolCards();
const defaultCleared = {{removed, timerClears, intentClears, legacy: legacy.innerHTML, legacyDisplay: legacy.style.display}};
console.log(JSON.stringify({{preserved, defaultCleared}}));
""")
res = subprocess.run(["node", "-e", harness], capture_output=True, text=True, timeout=30)
assert res.returncode == 0, res.stderr
out = json.loads(res.stdout.strip())
assert out["preserved"] == {
"removed": 0,
"timerClears": 1,
"intentClears": 1,
"legacy": "",
"legacyDisplay": "none",
}, "preserveDom cleanup must leave the live worklog visible until the settled render replaces it"
assert out["defaultCleared"]["removed"] == 2, "error/cancel cleanup must still remove live rows"
assert out["defaultCleared"]["legacy"] == "", "default cleanup must still clear the legacy container"
assert out["defaultCleared"]["legacyDisplay"] == "none", "legacy cleanup must hide the container"
assert "clearLiveToolCards({preserveDom:true})" in done, (
"the normal done handler must preserve the visible live Worklog until its "
"settled transcript render replaces it"
)
@pytest.mark.skipif(shutil.which("node") is None, reason="node required for behavioral test")
def test_in_place_collapse_preserves_detail_disclosure_for_deferred_materialize():
"""A just-settled in-place collapse must preserve nested detail open state.
The old full render path captured Worklog detail disclosure before rebuilding
and stashed that map on deferred groups. The new in-place path must do the
same before its rAF removes the rendered rows; otherwise a live-open tool
detail is lost when the user expands the collapsed settled Worklog.
"""
collapse = _extract("_collapseJustSettledWorklogInPlace")
visible_segment = _extract("_assistantTurnHasVisibleRenderedSegment")
materialize = _extract("_materializeDeferredWorklogRows")
harness = textwrap.dedent(f"""
const assert = require('assert');
const rows = [{{id: 'row-1'}}];
let activeGroup = null;
let capturedGroup = null;
let renderedRows = null;
let restoredState = null;
let removedRows = false;
let syncCount = 0;
let ownerHasVisibleSegment = true;
const S = {{
session: {{session_id: 'session-1'}},
// Keep the session-wide no-response guard false: a normal answered
// turn precedes the completed tool/reasoning-only turn under test.
messages: [
{{role: 'assistant', content: 'previous final answer'}},
{{role: 'assistant', content: '', _anchor_activity_scene: {{terminal_state: 'completed'}}}},
],
}};
const summary = {{
attrs: {{}},
setAttribute(name, value) {{ this.attrs[name] = String(value); }},
}};
const list = {{
replaceChildren() {{ removedRows = true; }},
}};
const inner = {{
querySelectorAll(selector) {{
if (selector === '[data-anchor-settled-scene-owner="1"]') return [activeGroup];
return [];
}},
}};
const visibleSegment = {{
textContent: 'previous final answer',
classList: {{ contains() {{ return false; }} }},
}};
const ownerTurn = {{
querySelectorAll(selector) {{
assert.strictEqual(selector, '.assistant-segment');
return ownerHasVisibleSegment ? [visibleSegment] : [];
}},
}};
function makeGroup() {{
return {{
attrs: {{
'data-anchor-stream-id': 'stream-1',
'data-activity-disclosure-key': 'anchor-scene:1',
}},
isConnected: true,
_deferredWorklogRows: null,
_deferredWorklogDisclosure: 'stale',
closest(selector) {{
assert.strictEqual(selector, '.assistant-turn');
return ownerTurn;
}},
getAttribute(name) {{ return this.attrs[name] || ''; }},
setAttribute(name, value) {{ this.attrs[name] = String(value); }},
removeAttribute(name) {{ delete this.attrs[name]; }},
querySelector(selector) {{
if (selector.includes('tool-worklog-summary') || selector.includes('tool-call-group-summary')) return summary;
return null;
}},
querySelectorAll() {{ return []; }},
classList: {{
values: new Set(['open']),
add(name) {{ this.values.add(name); }},
remove(name) {{ this.values.delete(name); }},
contains(name) {{ return this.values.has(name); }},
}},
}};
}}
function $(id) {{ return id === 'msgInner' ? inner : null; }}
function _readActivityDisclosureState() {{ return detailState; }}
function _deferredWorklogRowsFromGroup(group) {{ assert.strictEqual(group, activeGroup); return rows; }}
function _anchorSceneHasErroredTerminalState() {{ return false; }}
function _syncToolCallGroupSummary(group) {{ assert.strictEqual(group, activeGroup); syncCount += 1; }}
function _toolWorklogListEl(group) {{ assert.strictEqual(group, activeGroup); return list; }}
function _renderAnchorSceneRowsIntoWorklog(group, materializedRows) {{
assert.strictEqual(group, activeGroup);
renderedRows = materializedRows;
return true;
}}
function _postProcessWithAnchorSuppression() {{}}
function _restoreWorklogDetailDisclosureState(group, state) {{
assert.strictEqual(group, activeGroup);
restoredState = state;
}}
function requestAnimationFrame(callback) {{ callback(); }}
let detailState = null;
let defaultExpanded = false;
function _captureWorklogDetailDisclosureState(group) {{
capturedGroup = group;
return detailState;
}}
function _worklogDetailsExpandedDefault() {{ return defaultExpanded; }}
{visible_segment}
{collapse}
{materialize}
activeGroup = makeGroup();
detailState = new Map([['tool:read_file#0', {{open: true, scrollTop: 18}}]]);
assert.strictEqual(_collapseJustSettledWorklogInPlace('stream-1'), true);
assert.strictEqual(capturedGroup, activeGroup);
assert.strictEqual(activeGroup._deferredWorklogDisclosure, detailState);
assert.strictEqual(activeGroup._deferredWorklogRows, rows);
assert.strictEqual(activeGroup.attrs['data-worklog-rows-deferred'], '1');
assert.strictEqual(activeGroup.classList.contains('tool-call-group-collapsed'), true);
assert.strictEqual(removedRows, true);
assert.strictEqual(_materializeDeferredWorklogRows(activeGroup), true);
assert.strictEqual(restoredState, detailState);
assert.strictEqual(renderedRows, rows);
capturedGroup = null;
renderedRows = null;
restoredState = null;
removedRows = false;
activeGroup = makeGroup();
detailState = new Map();
assert.strictEqual(_collapseJustSettledWorklogInPlace('stream-1'), true);
assert.strictEqual(capturedGroup, activeGroup);
assert.strictEqual(activeGroup._deferredWorklogDisclosure, null);
assert.strictEqual(_materializeDeferredWorklogRows(activeGroup), true);
assert.strictEqual(restoredState, null);
assert.strictEqual(renderedRows, rows);
assert.strictEqual(syncCount, 2);
removedRows = false;
activeGroup = makeGroup();
detailState = null;
defaultExpanded = true;
ownerHasVisibleSegment = true;
assert.strictEqual(_collapseJustSettledWorklogInPlace('stream-1'), true);
assert.strictEqual(activeGroup._deferredWorklogRows, null);
assert.strictEqual(activeGroup.classList.contains('open'), true);
assert.strictEqual(activeGroup.classList.contains('tool-call-group-collapsed'), false);
assert.strictEqual(removedRows, false);
activeGroup = makeGroup();
detailState = 'closed';
ownerHasVisibleSegment = true;
assert.strictEqual(_collapseJustSettledWorklogInPlace('stream-1'), true);
assert.strictEqual(activeGroup._deferredWorklogRows, rows);
assert.strictEqual(activeGroup.classList.contains('tool-call-group-collapsed'), true);
assert.strictEqual(removedRows, true);
removedRows = false;
activeGroup = makeGroup();
detailState = 'closed';
defaultExpanded = false;
ownerHasVisibleSegment = false;
assert.strictEqual(_collapseJustSettledWorklogInPlace('stream-1'), true);
assert.strictEqual(activeGroup._deferredWorklogRows, null);
assert.strictEqual(activeGroup.classList.contains('open'), true);
assert.strictEqual(activeGroup.classList.contains('tool-call-group-collapsed'), false);
assert.strictEqual(removedRows, false);
console.log(JSON.stringify({{ok: true}}));
""")
res = subprocess.run(["node", "-e", harness], capture_output=True, text=True, timeout=30)
assert res.returncode == 0, res.stderr
assert json.loads(res.stdout.strip()) == {"ok": True}
@pytest.mark.skipif(shutil.which("node") is None, reason="node required for behavioral test")
def test_prescroll_snapshot_bypasses_capture_no_option_fallback_still_captures():
"""Sentinel _prescrollSnapshot reaches restore without re-capture.
Behavioral harness for _renderMessagesWithScrollSnapshot:
1. Supply a sentinel snapshot via _prescrollSnapshot, stub
_captureMessageScrollSnapshot with a counter — proves the
sentinel reaches _restoreMessageScrollSnapshotSameFrame
without a second capture.
2. Call with no options — proves the no-option fallback still
calls _captureMessageScrollSnapshot() normally (the contract
for callers at static/ui.js:9565, 14416, 14424).
3. Call with empty options {} — same fallback proof.
"""
wrapper = _extract("_renderMessagesWithScrollSnapshot")
harness = textwrap.dedent(f"""
let captureCount = 0;
let restoredSnapshot = null;
let renderedOptions = null;
globalThis._captureMessageScrollSnapshot = () => {{
captureCount++;
return {{_sentinel: 'fresh-capture', bottom: 0, pinned: true}};
}};
globalThis.renderMessages = (opts) => {{ renderedOptions = opts; }};
globalThis._restoreMessageScrollSnapshotSameFrame = (snap) => {{ restoredSnapshot = snap; }};
{wrapper}
// Test 1: supplied _prescrollSnapshot -> use it, do NOT capture
const sentinel = {{_sentinel: 'pre-captured', bottom: 42, pinned: true}};
_renderMessagesWithScrollSnapshot({{_prescrollSnapshot: sentinel}});
const test1_usedPrescroll = restoredSnapshot === sentinel;
const test1_noCapture = captureCount === 0;
const test1_preservedArgs = renderedOptions && renderedOptions._prescrollSnapshot === sentinel;
// Reset
captureCount = 0; restoredSnapshot = null; renderedOptions = null;
// Test 2: no options -> fall back to _captureMessageScrollSnapshot()
_renderMessagesWithScrollSnapshot();
const test2_captured = captureCount === 1;
const test2_usedCapture = restoredSnapshot && restoredSnapshot._sentinel === 'fresh-capture';
// Reset
captureCount = 0; restoredSnapshot = null; renderedOptions = null;
// Test 3: empty options object -> still fall back to capture
_renderMessagesWithScrollSnapshot({{}});
const test3_captured = captureCount === 1;
const test3_usedCapture = restoredSnapshot && restoredSnapshot._sentinel === 'fresh-capture';
console.log(JSON.stringify({{
test1_usedPrescroll,
test1_noCapture,
test1_preservedArgs,
test2_captured,
test2_usedCapture,
test3_captured,
test3_usedCapture
}}));
""")
res = subprocess.run(["node", "-e", harness], capture_output=True, text=True, timeout=30)
assert res.returncode == 0, res.stderr
out = json.loads(res.stdout.strip())
assert out["test1_usedPrescroll"] is True, (
"supplied _prescrollSnapshot must reach _restoreMessageScrollSnapshotSameFrame"
)
assert out["test1_noCapture"] is True, (
"supplied _prescrollSnapshot must bypass _captureMessageScrollSnapshot()"
)
assert out["test1_preservedArgs"] is True, (
"options passed to _renderMessagesWithScrollSnapshot must be forwarded to renderMessages"
)
assert out["test2_captured"] is True, (
"no-option call must fall back to _captureMessageScrollSnapshot()"
)
assert out["test2_usedCapture"] is True, (
"no-option call's captured snapshot must reach _restoreMessageScrollSnapshotSameFrame"
)
assert out["test3_captured"] is True, (
"empty-options call must fall back to _captureMessageScrollSnapshot()"
)
assert out["test3_usedCapture"] is True, (
"empty-options call's captured snapshot must reach _restoreMessageScrollSnapshotSameFrame"
)