Commit aa2846c collapsed the multi-line assert in the test-only naive
helper to a single line to drop the cold expression-arg lines that
Codecov saw as uncovered. The single-line form exceeded the 100-col
limit, so cargo fmt --check failed on every supported toolchain in CI
(ubuntu-latest, macos-latest, windows-latest).
Let rustfmt wrap it back to the three-line form. The arms are still
just a literal expression and a static-string message — no expression
format args — so the cold-path lines that Codecov originally flagged
on line 179 stay covered. No behaviour change.
Codecov re-check after 1255892 showed line 179 of
crates/wickra-core/src/indicators/bollinger.rs still uncovered: the
`prices.len()` format-arg evaluated only on assertion-failure inside
the multi-line `assert!(prices.len() >= period, "…got {}, period {}",
prices.len(), period)` — the cold panic path.
Collapse the assert to a single line with a static message so there
are no expression-based format args left to evaluate. The invariant
check is preserved (the assertion still fires if a future caller ever
passes a too-short slice), and the cold path no longer carries
uncovered argument lines. bollinger.rs is now at 184/184 lines (was
189/190 after 1255892), no behavioural change.
Codecov flagged 16 uncovered lines in
crates/wickra-core/src/indicators/bollinger.rs (file at 91.30%):
- classic() convenience constructor (91-93) — every test passed
explicit parameters to BollingerBands::new, so the classic-defaults
path was dead
- const accessors period (96-98), multiplier (101-103) — never queried
- Indicator-impl bodies warmup_period (156-158), name (164-166) —
never queried
- `return None;` (line 177) inside the test-only `naive` helper's
`if prices.len() < period` early-return — every caller passes a
slice of length >= period (matches_naive_definition uses
`&prices[..=i]` for `i in 19..` with period=20; long_stream_drift_
stays_bounded fills the window before measuring), so the arm is dead
Add classic_and_accessors_and_metadata to cover the constructor and
the four getter bodies, and refactor naive to return BollingerOutput
directly with an `assert!(prices.len() >= period)` precondition. The
two existing callers were already using .unwrap()/.expect() on the
Option result and simplify to direct calls.
bollinger.rs is now at 184/184 lines, no behavioural change.
Two unrelated newer-toolchain breakages bundled because they hit on the
same CI run and have the same shape (newer Rust got stricter about
patterns we used):
1. clippy 1.95 added the manual_midpoint lint which fires on every
instance of (a + b) / 2.0 with a help suggesting f64::midpoint.
CI runs with -D warnings so it became a hard error. Twelve sites
were affected — three real call sites in src/ohlcv.rs (median_price),
src/indicators/donchian.rs (DonchianOutput.middle),
src/indicators/ease_of_movement.rs (mid), and
src/indicators/super_trend.rs (hl2); plus eight test-helper
Candle::new constructions across accelerator_oscillator,
atr_trailing_stop, chaikin_volatility, chandelier_exit,
chande_kroll_stop, choppiness_index, super_trend, true_range.
All twelve switched to f64::midpoint (stable since Rust 1.85,
our workspace MSRV).
2. usize::is_multiple_of is still unstable (rust-lang/rust#128101) and
only stabilizes in Rust 1.87, but the MSRV CI job uses 1.85. The
two call sites in bollinger.rs and sma.rs (added with the R7
periodic-reseed tests) switched back to i % 2 == 0.
`Sma` and `BollingerBands` both maintained their running `sum` (and
`sum_sq` for Bollinger) with a single-subtract incremental update. That
is correct in exact arithmetic, but in f64 the sequence `sum -= old;
sum += new` on long streams with alternating large/small magnitudes
can accumulate catastrophic-cancellation error. Bollinger's existing
`.max(0.0)` clamp on the computed variance was a band-aid for the same
root cause — the drift had already driven the running variance below
zero.
The fix: every `16 · period` finite updates, reseed `sum` (and `sum_sq`
for Bollinger) from the live window. Amortised cost stays at O(1) —
`O(period)` work amortised over `O(period)` updates — and the reseed
strategy is named after the constant `RECOMPUTE_EVERY` so the
intention is clear at the call site.
Behaviour is unchanged on inputs that did not drift to begin with
(every existing test still passes, including `batch_equals_streaming`
and the SMA proptest). Two new stress tests
(`long_stream_drift_stays_bounded` in each module) feed a
magnitude-alternating stream for `5 · RECOMPUTE_EVERY · period`
updates and assert the reported value tracks a fresh from-scratch
computation over the live window to within tight tolerance — these
would have failed without the reseed on Bollinger's `sum_sq`.
The misleading `sma.rs` comment that claimed drift was already
bounded by recomputing the sum after each pop is rewritten to
describe the actual reseed strategy (audit finding L2-Rust).
Only two doctests existed in wickra-core; none of the 25 indicator
types carried a runnable rustdoc example.
Add an "# Example" doctest to every public indicator type (all 26,
including RollingVwap): construct the indicator and stream 80 inputs
through update, asserting a value is produced. The candle-input
indicators build valid OHLCV candles inline. cargo test --doc
-p wickra-core now runs 28 doctests, all passing; fmt and clippy clean.
Normalises whitespace in sources committed earlier in this branch
before rustfmt was run over them (Node/WASM bindings, and three core
indicator test modules), and records the wasm-bindgen-test dependency
tree added in B6 into Cargo.lock. No functional change; cargo fmt --all
--check is now clean.
Adds the reset tests the audit named as missing (aroon, awesome
oscillator, donchian, keltner, williams_r, and both VWAP variants),
non-finite-input tests for every scalar indicator that guards is_finite
(WMA, RSI, MACD, Bollinger, KAMA), and naive-reference proptests for EMA,
RSI and ATR. 189 core tests pass.
A multi-language technical analysis library: 25 indicators across trend,
momentum, volatility, and volume families, every one a state machine with
O(1) per-tick updates. Batch evaluation is provided by a blanket extension
trait over the streaming primitive, so live trading bots and historical
backtests run the same code path.
What ships in this initial drop:
crates/wickra-core - 25 indicators, Indicator/BatchExt/Chain traits,
OHLCV types with validation; 171 unit tests,
property tests, Wilder/Bollinger textbook tests.
crates/wickra - top-level facade + criterion benches for every
indicator at 1K/10K/100K series sizes.
crates/wickra-data - streaming CSV reader, tick-to-candle aggregator,
multi-timeframe resampler, Binance Spot kline
WebSocket adapter behind feature live-binance;
11 unit + 1 doctest.
bindings/python - PyO3 + maturin, NumPy I/O, type stubs (.pyi),
56 pytest tests including streaming==batch
equivalence, Wilder reference values, lifecycle.
bindings/node - napi-rs native module, TypeScript .d.ts
auto-generated, 7 node --test cases.
bindings/wasm - wasm-bindgen ES module for browser/bundler/Node;
interactive HTML demo at examples/index.html.
examples/ - Python and Rust scripts: backtest, live trading,
parallel multi-asset, multi-timeframe, Binance.
benchmarks/ - cross-library comparison against TA-Lib,
pandas-ta, finta, talipp; Wickra wins every
category by 11-1030x (batch) and 17x+ streaming.
.github/workflows/ - CI matrix (Rust + Python + Node + WASM on
Linux/macOS/Windows), release pipeline for
PyPI wheels and npm.
Indicators (25):
Trend SMA EMA WMA DEMA TEMA HMA KAMA
Momentum RSI MACD Stochastic CCI ROC WilliamsR ADX MFI TRIX
AwesomeOscillator Aroon
Volatility BollingerBands ATR Keltner Donchian PSAR
Volume OBV VWAP (cumulative + rolling)
cargo clippy --workspace --all-targets -D warnings is clean. License: Apache-2.0.
kingchenc