Files
pragent/tests/pilot/test_cost_model.py
T
Marcos 998f793ec2 feat(agent): tighten prompt to bound beyond-diff reads + de-generalize cost-model labels
Three changes from operator feedback:

1. Per-comment � attribution restored on inline comments (operator wants
   it back — the PR-level collapsible is collapsed by default, so the
   attribution is the visible signal of per-finding cost share).
   Hidden only when no _tok_attrib was computed (legacy callers / ollama
   path without usage metering).

2. Agent prompt now bounds reads beyond the diff — the single biggest
   driver of input-token bloat on long agent loops:
     * ≤ 5 file reads beyond the diff for the entire review
     * ≤ 80 lines per read (use --offset + --limit)
     * ≤ 3 grep calls beyond the diff (prefer rtk grep)
     * no re-reads of files already seen
     * no directory walks (ls -R, find .)
     * honor .pr-review.json:exclude_paths

3. De-generalize cost_model calibration labels. The OBSERVED_RUNS list
   referred to `gitea_admin/pragent#7` — a real internal repo path that
   blocks commercialization. Replaced with `internal/hardening-PR (16
   files, 1020 insertions / 91 deletions)`. The numbers (input/output
   tokens, steps, duration) are unchanged — only the labels are
   generic.

Tests:
  * test_inline_comment_body_with_attribution_line — asserts 🪙 line
    shows when _tok_attrib is set
  * test_inline_comment_body_no_attribution_no_coin_line — still
    verifies the line is hidden when no attribution data
  * test_observed_report_prices_every_model — asserts no internal
    repo name appears in the rendered report
Co-Authored-By: Claude <noreply@anthropic.com>
2026-08-20 17:35:06 +00:00

247 lines
8.7 KiB
Python

"""Unit tests for the per-review cost model. No network."""
import os
import sys
HERE = os.path.dirname(os.path.abspath(__file__))
ROOT = os.path.abspath(os.path.join(HERE, "..", ".."))
sys.path.insert(0, os.path.join(ROOT, "pilot"))
import cost_model as cm # noqa: E402
FACTORY = cm.measure_factory(ROOT)
# ---------------------------------------------------------------------------
# measure_factory — reads the real files
# ---------------------------------------------------------------------------
def test_measure_factory_finds_agent_and_skills():
assert FACTORY["agent"] > 500
for skill in cm.ALWAYS_SKILLS:
assert FACTORY[f"skill:{skill}"] > 100, skill
for lens in ("security", "tests", "perf"):
assert FACTORY[f"subagent:{lens}"] > 100, lens
def test_measure_factory_missing_root_is_empty_not_an_error():
f = cm.measure_factory("/nonexistent-path-for-test")
assert f == {"agent": 0, "subagent:security": 0, "subagent:tests": 0, "subagent:perf": 0}
# ---------------------------------------------------------------------------
# prefix_tokens — tiers load different skill sets
# ---------------------------------------------------------------------------
def test_prefix_grows_with_tier():
sizes = [cm.prefix_tokens(t, FACTORY) for t in ("trivial", "lite", "full", "oversized")]
assert sizes == sorted(sizes)
assert sizes[0] < sizes[-1]
def test_prefix_includes_harness_and_agent():
assert cm.prefix_tokens("trivial", FACTORY) > cm.HARNESS_TOKENS + FACTORY["agent"]
def test_unknown_tier_still_returns_the_always_skills():
assert cm.prefix_tokens("nope", FACTORY) == cm.prefix_tokens("trivial", FACTORY)
# ---------------------------------------------------------------------------
# tier_usage — the loop's resend behaviour is what costs money
# ---------------------------------------------------------------------------
def _tier(name):
return next(t for t in cm.DEFAULT_TIERS if t.name == name)
def test_caching_moves_the_stable_prefix_out_of_uncached_input():
t = _tier("full")
cached = cm.tier_usage(t, FACTORY, caching=True)
uncached = cm.tier_usage(t, FACTORY, caching=False)
assert cached.uncached_input < uncached.uncached_input
assert cached.cached_input > 0
assert uncached.cached_input == 0
assert uncached.cache_writes == 0
def test_total_input_is_the_same_work_either_way():
# Caching changes the *price* of the tokens, not how many are sent.
t = _tier("full")
a = cm.tier_usage(t, FACTORY, caching=True)
b = cm.tier_usage(t, FACTORY, caching=False)
# With caching the step-1 stable block is billed as a cache write rather
# than as input, so it moves columns — the grand total of tokens sent is
# identical.
assert a.total_input + a.cache_writes == b.total_input
def test_more_steps_cost_more_input():
base = _tier("lite")
more = cm.Tier(
"lite-long", base.diff_tokens, base.steps * 2, base.file_reads,
base.tokens_per_read, base.output_tokens,
)
assert cm.tier_usage(more, FACTORY).total_input > cm.tier_usage(base, FACTORY).total_input
def test_trivial_tier_does_no_tool_work():
u = cm.tier_usage(_tier("trivial"), FACTORY)
assert u.uncached_input == 0 # no tool-result tail at all
assert u.output > 0
def test_subagents_add_input_and_output():
t = _tier("full")
with_subs = cm.Tier(
t.name, t.diff_tokens, t.steps, t.file_reads, t.tokens_per_read,
t.output_tokens, subagents=2,
)
a, b = cm.tier_usage(t, FACTORY), cm.tier_usage(with_subs, FACTORY)
assert b.total_input > a.total_input
assert b.output > a.output
# ---------------------------------------------------------------------------
# cost — prices and discounts
# ---------------------------------------------------------------------------
def test_cost_is_ordered_by_model_price():
u = cm.tier_usage(_tier("full"), FACTORY)
opus = cm.cost(u, cm.PRICES["claude-opus-5"])
sonnet = cm.cost(u, cm.PRICES["claude-sonnet-5"])
haiku = cm.cost(u, cm.PRICES["claude-haiku-4-5"])
assert opus > sonnet > haiku > 0
def test_batch_is_exactly_half():
u = cm.tier_usage(_tier("full"), FACTORY)
p = cm.PRICES["claude-opus-5"]
assert abs(cm.cost(u, p, batch=True) * 2 - cm.cost(u, p)) < 1e-9
def test_cost_matches_a_hand_calculation():
u = cm.Usage(uncached_input=1_000_000, cached_input=1_000_000,
cache_writes=1_000_000, output=1_000_000)
p = cm.PRICES["claude-opus-5"] # 5 / 25 / 6.25 / 0.50
assert abs(cm.cost(u, p) - (5.00 + 0.50 + 6.25 + 25.00)) < 1e-9
def test_caching_is_cheaper_than_not_caching():
for name in ("lite", "full", "oversized"):
t = _tier(name)
p = cm.PRICES["claude-opus-5"]
assert cm.cost(cm.tier_usage(t, FACTORY, True), p) < \
cm.cost(cm.tier_usage(t, FACTORY, False), p), name
def test_cost_rises_monotonically_with_tier():
p = cm.PRICES["claude-sonnet-5"]
costs = [cm.cost(cm.tier_usage(_tier(n), FACTORY), p)
for n in ("trivial", "lite", "full", "oversized")]
assert costs == sorted(costs)
# ---------------------------------------------------------------------------
# blended + CLI
# ---------------------------------------------------------------------------
def test_blended_sits_between_the_cheapest_and_priciest_tier():
p = cm.PRICES["claude-opus-5"]
blended = cm.blended_cost(cm.DEFAULT_TIERS, FACTORY, p, True)
per_tier = [cm.cost(cm.tier_usage(t, FACTORY), p) for t in cm.DEFAULT_TIERS]
assert min(per_tier) < blended < max(per_tier)
def test_shares_that_do_not_sum_to_one_are_normalised():
p = cm.PRICES["claude-opus-5"]
tiers = [cm.Tier(t.name, t.diff_tokens, t.steps, t.file_reads,
t.tokens_per_read, t.output_tokens, t.subagents, share=t.share * 2)
for t in cm.DEFAULT_TIERS]
doubled = cm.blended_cost(tiers, FACTORY, p, True)
normal = cm.blended_cost(cm.DEFAULT_TIERS, FACTORY, p, True)
assert abs(doubled - normal) < 1e-9
def test_report_renders_every_requested_model():
text = cm.report(cm.DEFAULT_TIERS, 350, True, ["claude-opus-5", "gpt-5.6-luna"])
assert "Claude Opus 5" in text
assert "GPT-5.6 Luna" in text
assert "Claude Sonnet 5" not in text
assert "350 PRs/month" in text
def test_main_rejects_unknown_model(capsys):
try:
cm.main(["--models", "gpt-9"])
except SystemExit as e:
assert e.code != 0
else:
raise AssertionError("expected SystemExit")
def test_main_rejects_bad_mix():
try:
cm.main(["--mix", "50,50"])
except SystemExit as e:
assert e.code != 0
else:
raise AssertionError("expected SystemExit")
def test_main_runs(capsys):
assert cm.main(["--models", "claude-sonnet-5", "--prs-per-month", "10"]) == 0
assert "per month" in capsys.readouterr().out
# ---------------------------------------------------------------------------
# observed runs — the calibration anchor
# ---------------------------------------------------------------------------
def test_observed_runs_are_well_formed():
assert cm.OBSERVED_RUNS, "the model is a guess without at least one measurement"
for run in cm.OBSERVED_RUNS:
for key in ("label", "date", "tier", "steps", "input", "output",
"cache_read", "cache_write"):
assert key in run, f"{run.get('label')} missing {key}"
assert run["input"] > 0 and run["output"] > 0
assert run["tier"] in {t.name for t in cm.DEFAULT_TIERS}
def test_observed_usage_splits_cached_from_uncached():
run = {"input": 1000, "output": 100, "cache_read": 400, "cache_write": 50}
u = cm.observed_usage(run)
assert u.cached_input == 400
assert u.uncached_input == 600
assert u.cache_writes == 50
assert u.total_input == 1000
def test_observed_report_prices_every_model():
text = cm.observed_report(["claude-opus-5", "gpt-5.6-luna"])
assert "Claude Opus 5" in text
assert "GPT-5.6 Luna" in text
# Labels are generic (no internal repo names) for commercialization.
assert "gitea_admin" not in text
assert "internal/hardening-PR" in text
def test_model_is_within_an_order_of_magnitude_of_the_measurement():
# The first measurement corrected the tier assumptions by ~15x. This guards
# against drifting that far out again: predict the observed run's tier at
# its actual diff size and step count, and compare to what was measured.
run = cm.OBSERVED_RUNS[0]
base = _tier(run["tier"])
modelled = cm.Tier(
base.name, run["diff_tokens"], run["steps"], base.file_reads,
base.tokens_per_read, run["output"], run["subagents"],
)
predicted = cm.tier_usage(modelled, FACTORY, caching=False).total_input
measured = run["input"]
assert 0.4 < predicted / measured < 2.5, (predicted, measured)