## Summary
Closes two Chunker migration gaps documented in
`docs/migration_python_go_diff.md`
(diffs **2.6** and **1.7**), improving parity with the Python ingestion
pipeline.
This is the code portion of commit `261e1fd0b` on branch
`fix/batch-3-4`; the
migration document itself is tracked separately (untracked in this
commit).
### Diff 2.6 — `overlapped_percent` missing Python normalization
Python's `normalize_overlapped_percent` (`common/float_utils.py:50-58`)
accepts a
`[0,1)` fraction (the flow-canvas UI validates `[0,1)`), multiplies it
by 100,
`int()`-truncates, and clamps to `[0,90]`. Go previously only accepted a
raw
`[0,90]` percentage and **rejected** out-of-range input, so a Python
config
passing `0.1` (meaning 10%) silently produced ~0% overlap.
Added `normalizeOverlappedPercent`
(`internal/ingestion/component/chunker/common.go`) mirroring the Python
helper:
- parses numbers and numeric strings (mirrors Python `float()`; bad /
`NaN` / `Inf` → `0`),
- `0 < v < 1 → v *= 100`,
- `int()` truncation,
- clamps to `[0,90]`.
Wired into `tokenChunkerParam.Update` (`token.go`); the merge math
(`token.go:705`, `(100-x)/100`) already matched Python.
`TokenChunkerParam.Validate`
(`schema/chunker.go`) now only guards direct struct construction.
Tests: `TestNormalizeOverlappedPercent`, extended
`TestTokenChunker_NewAcceptsPythonOverlappedRange` (adds fraction/clamp
inputs),
new `TestTokenChunker_NormalizesOverlappedPercent`. The existing
reject-test cases
for `<0` / `>90` were removed because they are now normalized/clamped
(Python parity).
### Diff 1.7 — missing `BULLET_PATTERN` title-level fallback
`resolveTitleLevels` (`title.go`) now applies a 4th-level fallback: when
outline +
regex + layout all yield body level, `bulletsCategory` selects the
best-matching
bullet-pattern group (Chinese legal / numbering / Chinese numbering /
English legal
— mirroring `rag/nlp/__init__.py:258-320`) and assigns structural
levels. Guarded by
`allBodyLevel` so it never overrides an existing outline/regex level.
Tests: `TestResolveTitleLevels_BulletFallback` (4 subtests).
### Incidental test adjustments included in the commit
- `token_batch1_test.go`: overlap input changed `0.3` → `30.0` to
reflect the
post-normalization 30% semantics.
- `real_consumer_test.go`: updated `LoadFromIngestionTask(task)` →
`LoadFromIngestionTask(ctx, task)` for the new context-first signature.
## Verification
`bash build.sh --test ./internal/ingestion/component/...` — chunker +
schema suites
pass, no regression (CGO build).
## Migration doc reference
`docs/migration_python_go_diff.md` §Chunker 1.7 and 2.6 are marked
**Fixed** for
these changes.
