hermes-agent/tests/agent/lsp/test_service.py
Teknium 19071529f6
fix(lsp): shift baseline diagnostics into post-edit coordinates (#25978)
Pre-existing diagnostics below an edit point used to surface as 'LSP
diagnostics introduced by this edit' whenever the edit deleted or
inserted lines.  The delta-filter key included the diagnostic's
range, so the same logical error reported at a different line in
the post-edit snapshot looked like a brand new diagnostic.

Concrete case: deleting 14 lines in cli.py caused Pyright errors at
lines 9873, 10590, 12413, 13004 (unrelated to the edit) to be
reported as introduced by it.

Fix: build a piecewise-linear line-shift map (via difflib's
SequenceMatcher) from pre and post content, and remap baseline
diagnostics into post-edit coordinates before the set-difference.
Diagnostics in deleted regions drop out cleanly; diagnostics below
the edit shift by the right amount; diagnostics above are untouched.
The strict (range-aware) equality key stays — so a genuinely new
instance of an identical error class at a different line still
surfaces as new.

Pieces:
- agent/lsp/range_shift.py — build_line_shift, shift_diagnostic_range,
  shift_baseline.  Pure functions, no LSP state.
- agent/lsp/manager.py — LSPService.get_diagnostics_sync gains an
  optional line_shift kwarg; baseline is shift_baseline'd before
  computing the seen-set.  _diag_key keeps the strict range key.
- tools/file_operations.py — write_file captures pre_content for any
  LSP-handled extension (not just LINTERS_INPROC) and passes pre/post
  to _maybe_lsp_diagnostics, which builds the shift map.
- New _lsp_handles_extension helper guards the pre_content read.

Trade-offs preserved:
- Genuinely new same-class errors at different lines still surface
  (content-only key would have swallowed them).
- Pre-existing errors at unshifted positions still get filtered
  (covered by the strict-key path with no shift).
- Best-effort: when pre_content can't be captured (file didn't
  exist, permissions), the unshifted comparison still catches
  most pre-existing errors; the edge case it misses is a new file
  with a non-empty baseline, which is structurally impossible.
2026-05-14 15:56:07 -07:00

178 lines
5 KiB
Python

"""Tests for the synchronous LSPService wrapper.
Drives the service through ``snapshot_baseline`` →
``get_diagnostics_sync`` against the mock LSP server, exercising the
delta filter that ``tools/file_operations._check_lint_delta`` relies
on.
"""
from __future__ import annotations
import os
import sys
from pathlib import Path
import pytest
from agent.lsp.manager import LSPService
from agent.lsp.servers import (
SERVERS,
ServerContext,
ServerDef,
SpawnSpec,
find_server_for_file,
)
MOCK_SERVER = str(Path(__file__).parent / "_mock_lsp_server.py")
def _install_mock_server(monkeypatch, script: str = "errors", server_id: str = "pyright"):
"""Replace one registered server with a wrapper that spawns the mock.
We reuse ``pyright`` so .py files route to it. This keeps the
test free of any LSP toolchain dependency.
"""
target_index = next(i for i, s in enumerate(SERVERS) if s.server_id == server_id)
original = SERVERS[target_index]
def _spawn(root: str, ctx: ServerContext) -> SpawnSpec:
env = {"MOCK_LSP_SCRIPT": script}
return SpawnSpec(
command=[sys.executable, MOCK_SERVER],
workspace_root=root,
cwd=root,
env=env,
initialization_options={},
)
replacement = ServerDef(
server_id=server_id,
extensions=original.extensions,
resolve_root=lambda fp, ws: ws, # always use workspace root
build_spawn=_spawn,
seed_first_push=False,
description="mock " + server_id,
)
# Patch the SERVERS list element directly + restore on teardown.
SERVERS[target_index] = replacement
yield
SERVERS[target_index] = original
@pytest.fixture
def mock_pyright(monkeypatch, tmp_path):
"""Install the mock as ``pyright`` and create a fake git workspace."""
repo = tmp_path / "repo"
repo.mkdir()
(repo / ".git").mkdir()
(repo / "pyproject.toml").write_text("") # so pyright's root resolver finds it
monkeypatch.chdir(str(repo))
gen = _install_mock_server(monkeypatch, "errors", "pyright")
next(gen)
yield repo
try:
next(gen)
except StopIteration:
pass
def test_service_returns_empty_when_disabled(tmp_path):
svc = LSPService(
enabled=False,
wait_mode="document",
wait_timeout=2.0,
install_strategy="auto",
)
assert not svc.is_active()
f = tmp_path / "x.py"
f.write_text("")
assert svc.get_diagnostics_sync(str(f)) == []
svc.shutdown()
def test_service_skips_files_outside_workspace(tmp_path):
"""Files outside any git worktree must not trigger LSP."""
svc = LSPService(
enabled=True,
wait_mode="document",
wait_timeout=2.0,
install_strategy="manual",
)
f = tmp_path / "x.py"
f.write_text("")
# No .git anywhere — service should report not enabled for this file.
assert not svc.enabled_for(str(f))
svc.shutdown()
def test_service_e2e_delta_filter(mock_pyright):
"""End-to-end: snapshot baseline → wait → delta returned."""
repo = mock_pyright
f = repo / "x.py"
f.write_text("print('hi')\n")
svc = LSPService(
enabled=True,
wait_mode="document",
wait_timeout=3.0,
install_strategy="manual",
)
try:
assert svc.enabled_for(str(f))
# Baseline first — server pushes 1 error.
svc.snapshot_baseline(str(f))
# Re-poll: same error is in baseline, so delta is empty.
new_diags = svc.get_diagnostics_sync(str(f))
assert new_diags == []
finally:
svc.shutdown()
def test_service_e2e_delta_filter_with_line_shift(mock_pyright):
"""End-to-end: an edit that shifts the diagnostic's line still
filters correctly when ``line_shift`` is supplied.
The mock LSP server emits a fixed error at line 0; for this test
we don't need to actually shift the server's output — we just
need to prove that supplying a line_shift through the API works
and doesn't break the existing delta path. The unit tests in
test_delta_key.py cover the shift semantics in detail.
"""
repo = mock_pyright
f = repo / "x.py"
f.write_text("print('hi')\n")
svc = LSPService(
enabled=True,
wait_mode="document",
wait_timeout=3.0,
install_strategy="manual",
)
try:
svc.snapshot_baseline(str(f))
# Identity shift — should behave exactly like no shift.
new_diags = svc.get_diagnostics_sync(str(f), line_shift=lambda L: L)
assert new_diags == []
finally:
svc.shutdown()
def test_service_status_includes_clients(mock_pyright):
repo = mock_pyright
f = repo / "x.py"
f.write_text("")
svc = LSPService(
enabled=True,
wait_mode="document",
wait_timeout=3.0,
install_strategy="manual",
)
try:
svc.get_diagnostics_sync(str(f))
info = svc.get_status()
assert info["enabled"] is True
assert any(c["server_id"] == "pyright" for c in info["clients"])
finally:
svc.shutdown()