* feat(family-16): add ValueArea + InitialBalance + OpeningRange
Opens family #16 (Market Profile) with the three OHLCV-compatible scalar /
multi-output indicators:
- ValueArea(period, bin_count, value_area_pct) -> {poc, vah, val}.
Rolling bin-approximation volume profile over the last `period`
candles. Each candle's volume is spread uniformly across [low, high];
POC is the bin with highest cumulative volume; the value area expands
symmetrically from POC and always absorbs the higher-volume neighbour
next, until `value_area_pct` (default 0.70) of total volume is
enclosed. Defaults (20, 50, 0.70).
- InitialBalance(period) -> {high, low}. Tracks session-opening high
and low over the first `period` bars, then locks. Default period = 12
(one-hour IB on 5-minute bars for US equities). Callers MUST invoke
reset() at every session boundary, otherwise IB stays fixed for the
lifetime of the instance.
- OpeningRange(period) -> {high, low, breakout_distance}. Same
lock-after-N-bars semantics as IB with a shorter default period
(6 = 30 min on 5-minute bars) and a third output that tracks
close - or_mid (positive above the range mid, negative below).
Histogram-output Market Profile variants (Volume Profile, VPVR,
Composite Profile) are deferred because they need a new histogram
output API layer rather than fixed-arity scalars. Tick-data-only
variants (TPO Profile, Single Print, Order Flow Delta, Cumulative
Delta, Volume-Weighted Open) are out of scope because `wickra-data`
does not currently expose tick / L2 data.
All four bindings (Rust core, Python, Node, WASM) ship the new
indicators with parity tests; benches added; fuzz target extended.
Counter 71 -> 74 across 8 -> 9 families. cargo check --workspace
--all-features green.
* fix(family-16): cover cold paths in InitialBalance + ValueArea
InitialBalance::value() public getter had no test covering the post-update
Some(...) branch — extended accessors_and_metadata to call value() after one
update. ValueArea single-print bar path (c.high == c.low) was unreachable in
existing tests since the only single-print test used a uniform 100-price
window which exits early via the span == 0 guard; added a mixed-window test
that triggers the c.high <= c.low branch directly. The (None, None) arm of
the expansion match was by-construction unreachable (the loop condition
already requires at least one neighbour) and has been folded into an
if/else.
kingchenc
9b8e1346ed