refactor(rename): kb crates → kebab — Cargo packages, folders, Rust modules

프로젝트 이름 `kb` → `kebab` rename 의 첫 단계.

- workspace `Cargo.toml`: members `crates/kb-*` → `crates/kebab-*`,
  repository URL `altair823/kb` → `altair823/kebab`.
- 18 crate 폴더 rename via `git mv` (history 보존).
- 각 crate `Cargo.toml`: `name = "kb-*"` → `"kebab-*"`, path deps
  `../kb-*` → `../kebab-*`.
- 모든 `.rs`: `kb_<id>` snake-case 모듈 path 18 개 (`kb_core`,
  `kb_config`, `kb_app`, `kb_cli`, `kb_eval`, `kb_search`, `kb_chunk`,
  `kb_normalize`, `kb_source_fs`, `kb_parse_md`, `kb_parse_types`,
  `kb_store_sqlite`, `kb_store_vector`, `kb_embed`, `kb_embed_local`,
  `kb_llm`, `kb_llm_local`, `kb_rag`) → `kebab_<id>` 일괄 sed (단어
  경계 \\b 사용해 영어 문장 안의 "kb" 약어 미오염).

CLI binary 이름 (`[[bin]] name = "kb"`), 환경변수 `KB_*`, XDG paths,
tracing target, 그리고 docs sweep 은 다음 commit 에서.

## 검증

- `cargo check --workspace` clean — 모든 crate 빌드 통과 후 commit.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-05-02 03:28:08 +00:00
parent 2aecbf3d9f
commit 911fb49550
143 changed files with 727 additions and 727 deletions

View File

@@ -0,0 +1,835 @@
//! `md-heading-v1` — heading-aware Markdown chunker.
use kebab_core::{
Block, BlockId, CanonicalDocument, Chunk, ChunkPolicy, Chunker,
ChunkerVersion, DocumentId, SourceSpan, id_for_chunk,
};
/// Version label emitted by [`MdHeadingV1Chunker`]. Bumping this label
/// invalidates every downstream embedding record (design §9), so any change
/// must ship with a documented migration plan.
const VERSION_LABEL: &str = "md-heading-v1";
/// Bytes-per-token proxy. We over-estimate (smaller divisor → larger
/// token count) so that real tokenizers downstream never see a chunk
/// exceeding their budget. English averages ~4 bytes/token under BPE,
/// Korean averages ~3 bytes/token under E5; picking 3 covers both.
const BYTES_PER_TOKEN: usize = 3;
/// Maximum hex characters of `blake3(canonical_json(policy))` retained
/// in `policy_hash`. 16 hex chars = 64 bits of policy entropy, which is
/// far beyond enough to disambiguate the handful of policy variants a
/// single workspace will see.
const POLICY_HASH_HEX_LEN: usize = 16;
/// Heading-aware Markdown chunker.
///
/// Implements [`kebab_core::Chunker`] for Markdown-derived
/// [`CanonicalDocument`]s.
///
/// **Behavior contract** (design §0 / §14, in priority order):
///
/// 1. **Heading boundary first.** Chunks never span a `Block::Heading`.
/// The Heading block itself starts a new chunk and is included in that
/// chunk's `block_ids` so heading text is retrievable.
/// 2. **Never split a code block.** A `Block::Code` always lives in a
/// single chunk even when it exceeds `target_tokens`.
/// 3. **Tables stay in one chunk.** A `Block::Table` is emitted as a
/// single chunk regardless of size — the row-split refinement is
/// deferred per the P1-5 task spec.
/// 4. **Long sections split by paragraph.** Within a heading section
/// the chunker accumulates blocks until adding the next would exceed
/// `target_tokens`; it then emits the chunk and seeds the next chunk
/// with the previous chunk's tail blocks contributing roughly
/// `overlap_tokens` of content (paragraph-level overlap).
/// 5. **`heading_path` propagates.** Each chunk's `heading_path` is the
/// `heading_path` of its first contributing non-Heading block, or —
/// when the chunk leads with (or contains only) a Heading — the
/// parent path **plus the heading's own text** so heading-only or
/// heading-led chunks never lose their citation context.
/// 6. **`source_spans` merge.** A chunk lists every contributing block's
/// `source_span` in document order.
/// 7. **Version + policy hash recorded.** Each chunk records
/// `chunker_version = "md-heading-v1"`. The current `policy_hash` is
/// folded into the `chunk_id` recipe (design §4.2) so changing
/// `target_tokens` / `overlap_tokens` produces fresh chunk IDs.
///
/// `ImageRef` and `AudioRef` blocks are emitted as their own chunks so
/// future image/audio search can locate them. Their `text` is the alt /
/// caption preview (empty string if unavailable) and `token_estimate = 0`.
///
/// **Token-estimate proxy.** Until a real tokenizer is wired in (P3), the
/// estimator counts UTF-8 bytes and divides by [`BYTES_PER_TOKEN`]. The
/// constant is deliberately small (3) so the proxy *over*-estimates token
/// count — chunks sized against this proxy are guaranteed to fit in any
/// real BPE tokenizer's budget for English (~4 bytes/token) or Korean
/// (~3 bytes/token under E5/M-BERT). See [`BYTES_PER_TOKEN`] for rationale.
///
/// **`policy.respect_markdown_headings`.** This field flows into
/// `policy_hash` (so flipping it yields fresh chunk IDs), but the
/// chunker variant `md-heading-v1` unconditionally treats headings as
/// boundaries by design — the `md-heading-v1` name is the contract. To
/// disable heading awareness, ship a different `chunker_version`; none
/// is shipped in P1-5.
#[derive(Clone, Copy, Debug, Default)]
pub struct MdHeadingV1Chunker;
impl Chunker for MdHeadingV1Chunker {
fn chunker_version(&self) -> ChunkerVersion {
ChunkerVersion(VERSION_LABEL.to_string())
}
/// Compute the policy hash folded into `chunk_id` per design §4.2.
///
/// # Panics
///
/// Panics if canonical JSON serialization of `ChunkPolicy` fails.
/// This is unreachable in practice — `ChunkPolicy` is composed of
/// owned primitives (`usize`, `bool`, owned `String`) and
/// `serde_json_canonicalizer::to_vec` only fails on
/// non-serializable values such as non-finite floats or maps with
/// non-string keys, neither of which can be constructed via
/// `ChunkPolicy`'s public surface. The `expect` is preserved as a
/// future-proofing guard against drift if `ChunkPolicy` ever gains
/// a field with such a property.
fn policy_hash(&self, policy: &ChunkPolicy) -> String {
let bytes = serde_json_canonicalizer::to_vec(policy)
.expect("canonical JSON serialization of ChunkPolicy must not fail");
let hex = blake3::hash(&bytes).to_hex().to_string();
hex[..POLICY_HASH_HEX_LEN].to_string()
}
fn chunk(
&self,
doc: &CanonicalDocument,
policy: &ChunkPolicy,
) -> anyhow::Result<Vec<Chunk>> {
let policy_hash = self.policy_hash(policy);
let chunker_version = self.chunker_version();
let mut out: Vec<Chunk> = Vec::new();
// Running accumulator: the paragraphs/lists/quotes (and the
// optional leading heading) that will be glued into the next
// emitted chunk.
let mut acc = ChunkAcc::default();
for block in &doc.blocks {
match block {
Block::Heading(_) => {
// §0/§14 priority 1: heading is a hard boundary.
// Flush whatever has accumulated, then seed a new
// accumulator that owns this heading.
flush(&mut acc, doc, &chunker_version, &policy_hash, &mut out);
acc.push_block(block);
}
Block::Code(_) | Block::Table(_) => {
// Atomic non-splittable text blocks. Flush running
// accumulator, then emit the atomic block as its
// own chunk. (Code never splits per priority 2;
// tables stay single per priority 3.)
flush(&mut acc, doc, &chunker_version, &policy_hash, &mut out);
let mut single = ChunkAcc::default();
single.push_block(block);
flush(&mut single, doc, &chunker_version, &policy_hash, &mut out);
}
Block::ImageRef(_) | Block::AudioRef(_) => {
// Independent searchable artifacts. token_estimate=0
// is enforced inside `build_chunk` for these kinds.
flush(&mut acc, doc, &chunker_version, &policy_hash, &mut out);
let mut single = ChunkAcc::default();
single.push_block(block);
flush(&mut single, doc, &chunker_version, &policy_hash, &mut out);
}
Block::Paragraph(_) | Block::List(_) | Block::Quote(_) => {
// Soft-split candidates. If adding this block would
// exceed target_tokens (and we already have at least
// one non-heading block in the accumulator), emit
// the current chunk and seed the next one with
// overlap from the prior tail.
let next_tokens = estimate_block_tokens(block);
// Note: `acc.text_tokens` already includes the prior
// chunk's overlap seed. The clamp in
// `collect_overlap_seed` keeps seed ≤ target/2, so
// a flush here never produces a chunk smaller than
// the seed budget.
let would_exceed = acc.text_tokens + next_tokens
> policy.target_tokens
&& acc.has_non_heading_content();
if would_exceed {
let overlap_seed = collect_overlap_seed(
&acc,
policy.overlap_tokens,
policy.target_tokens,
);
flush(
&mut acc,
doc,
&chunker_version,
&policy_hash,
&mut out,
);
// Seed next accumulator with the prior chunk's
// tail blocks (paragraph-level overlap). The
// heading is *not* re-included here — it lives
// on the prior chunk. The follow-on chunk's
// heading_path is taken from the first seeded
// block (which carries the same path, as it sat
// under the same heading).
for b in overlap_seed {
acc.push_block(b);
}
}
acc.push_block(block);
}
}
}
flush(&mut acc, doc, &chunker_version, &policy_hash, &mut out);
tracing::debug!(
target: "kb-chunk",
doc_id = %doc.doc_id,
chunks = out.len(),
"md-heading-v1 chunked",
);
Ok(out)
}
}
/// Internal accumulator: pointers to blocks (lifetime-bound to the
/// `CanonicalDocument`) plus the running token estimate of their text.
#[derive(Default)]
struct ChunkAcc<'a> {
blocks: Vec<&'a Block>,
text_tokens: usize,
}
impl<'a> ChunkAcc<'a> {
fn push_block(&mut self, b: &'a Block) {
self.text_tokens += estimate_block_tokens(b);
self.blocks.push(b);
}
fn is_empty(&self) -> bool {
self.blocks.is_empty()
}
/// True if any non-heading block sits in the accumulator. Used to
/// avoid splitting a chunk that contains only its leading heading
/// (which would emit a heading-only chunk before any prose).
fn has_non_heading_content(&self) -> bool {
self.blocks.iter().any(|b| !matches!(b, Block::Heading(_)))
}
}
/// Drain `acc` into a fresh `Chunk` and push to `out`. No-op when empty.
fn flush(
acc: &mut ChunkAcc<'_>,
doc: &CanonicalDocument,
chunker_version: &ChunkerVersion,
policy_hash: &str,
out: &mut Vec<Chunk>,
) {
if acc.is_empty() {
return;
}
let blocks = std::mem::take(&mut acc.blocks);
acc.text_tokens = 0;
out.push(build_chunk(doc, &blocks, chunker_version, policy_hash));
}
/// Collect the trailing blocks of `acc` (in document order) whose
/// combined token estimate fits under the seed budget. The heading
/// block (if it leads the accumulator) is excluded from the seed —
/// re-emitting the heading would conflate it with the next chunk's
/// own heading_path provenance.
///
/// The seed budget is clamped to `min(overlap_tokens, target_tokens / 2)`.
/// Without the clamp, an `overlap_tokens >= target_tokens` policy
/// degenerates into 1-block-per-chunk: the seed already exceeds budget
/// before any new content lands, so the very next paragraph trips the
/// `would_exceed` flush. Halving the target guarantees the seed leaves
/// at least target/2 worth of room for fresh content in the next chunk.
fn collect_overlap_seed<'a>(
acc: &ChunkAcc<'a>,
overlap_tokens: usize,
target_tokens: usize,
) -> Vec<&'a Block> {
let seed_budget = overlap_tokens.min(target_tokens / 2);
if seed_budget == 0 {
return Vec::new();
}
let mut taken = Vec::new();
let mut budget = seed_budget;
for b in acc.blocks.iter().rev() {
if matches!(b, Block::Heading(_)) {
// Don't propagate the heading itself into the next chunk;
// its `heading_path` carries naturally on the next blocks
// (kb-normalize stamps every block under a heading with
// that heading's path).
continue;
}
let est = estimate_block_tokens(b);
if est > budget && !taken.is_empty() {
break;
}
taken.push(*b);
budget = budget.saturating_sub(est);
if budget == 0 {
break;
}
}
taken.reverse();
taken
}
/// Construct a `Chunk` from a non-empty contiguous slice of blocks.
fn build_chunk(
doc: &CanonicalDocument,
blocks: &[&Block],
chunker_version: &ChunkerVersion,
policy_hash: &str,
) -> Chunk {
debug_assert!(!blocks.is_empty(), "build_chunk requires ≥1 block");
let block_ids: Vec<BlockId> =
blocks.iter().map(|b| common(b).block_id.clone()).collect();
let source_spans: Vec<SourceSpan> =
blocks.iter().map(|b| common(b).source_span.clone()).collect();
// heading_path: pick the first non-Heading block's heading_path
// (which already includes every parent heading per kb-normalize).
// When the FIRST block is a Heading — either a heading-only chunk,
// or a chunk that leads with `# H1` immediately followed by another
// Heading or atomic block — the Heading block's own
// `common.heading_path` records only its *parents* (kb-normalize
// does not include a heading inside its own path). We synthesize
// the leading heading into the path so the citation context is not
// lost on patterns like `# Alpha\n## Beta\n...`.
let heading_path = match blocks[0] {
Block::Heading(h) => {
let mut path = h.common.heading_path.clone();
path.push(h.text.clone());
path
}
_ => common(blocks[0]).heading_path.clone(),
};
// Text rendering: simple double-newline join of each block's
// contribution. We deliberately pick a stable, low-fidelity
// representation — embedding-quality rewrites land in P3.
let mut text = String::new();
let mut is_image_or_audio_only = true;
for (i, b) in blocks.iter().enumerate() {
let part = render_block_text(b);
if !matches!(b, Block::ImageRef(_) | Block::AudioRef(_)) {
is_image_or_audio_only = false;
}
if i > 0 {
text.push_str("\n\n");
}
text.push_str(&part);
}
let token_estimate = if is_image_or_audio_only {
0
} else {
// Token estimate is bytes / BYTES_PER_TOKEN, rounded up so the
// proxy never under-counts.
text.len().div_ceil(BYTES_PER_TOKEN)
};
let chunk_id = id_for_chunk(
&doc.doc_id,
chunker_version,
&block_ids,
policy_hash,
);
Chunk {
chunk_id,
doc_id: DocumentId(doc.doc_id.0.clone()),
block_ids,
text,
heading_path,
source_spans,
token_estimate,
chunker_version: chunker_version.clone(),
policy_hash: policy_hash.to_string(),
}
}
/// Render a block's contribution to a chunk's `text`. The rendering is
/// deliberately minimal — embedding-time normalization is a P3 concern.
fn render_block_text(b: &Block) -> String {
match b {
Block::Heading(h) => h.text.clone(),
Block::Paragraph(p) | Block::Quote(p) => p.text.clone(),
Block::List(l) => l
.items
.iter()
.map(|it| it.text.as_str())
.collect::<Vec<_>>()
.join("\n"),
Block::Code(c) => c.code.clone(),
Block::Table(t) => {
// Headers row joined with " | ", then each row likewise.
let mut s = t.headers.join(" | ");
for row in &t.rows {
s.push('\n');
s.push_str(&row.join(" | "));
}
s
}
// ImageRef text portion = alt (per task spec). Fall back to
// model caption text if alt is empty.
Block::ImageRef(i) => {
if !i.alt.is_empty() {
i.alt.clone()
} else {
i.caption
.as_ref()
.map(|c| c.text.clone())
.unwrap_or_default()
}
}
// AudioRef has no caption preview yet (transcript joins land
// in P8). Empty string per task spec.
Block::AudioRef(_) => String::new(),
}
}
fn estimate_block_tokens(b: &Block) -> usize {
match b {
// ImageRef / AudioRef contribute 0 — they are independent
// chunks and never participate in size accounting.
Block::ImageRef(_) | Block::AudioRef(_) => 0,
_ => render_block_text(b).len().div_ceil(BYTES_PER_TOKEN),
}
}
/// Borrow the `CommonBlock` of any [`Block`] variant.
fn common(b: &Block) -> &kebab_core::CommonBlock {
match b {
Block::Heading(h) => &h.common,
Block::Paragraph(t) | Block::Quote(t) => &t.common,
Block::List(l) => &l.common,
Block::Code(c) => &c.common,
Block::Table(t) => &t.common,
Block::ImageRef(i) => &i.common,
Block::AudioRef(a) => &a.common,
}
}
#[cfg(test)]
mod tests {
use super::*;
use kebab_core::{
AssetId, CodeBlock, CommonBlock, HeadingBlock, ImageRefBlock, Lang,
Metadata, Provenance, SourceType, TableBlock, TextBlock, TrustLevel,
WorkspacePath, id_for_block,
};
use time::OffsetDateTime;
fn make_doc(blocks: Vec<Block>) -> CanonicalDocument {
CanonicalDocument {
doc_id: kebab_core::DocumentId("d".repeat(32)),
source_asset_id: AssetId("a".repeat(32)),
workspace_path: WorkspacePath::new("notes/test.md".into()).unwrap(),
title: "Test".into(),
lang: Lang("en".into()),
blocks,
metadata: Metadata {
aliases: vec![],
tags: vec![],
created_at: OffsetDateTime::from_unix_timestamp(1_700_000_000).unwrap(),
updated_at: OffsetDateTime::from_unix_timestamp(1_700_000_000).unwrap(),
source_type: SourceType::Note,
trust_level: TrustLevel::Primary,
user_id_alias: None,
user: Default::default(),
},
provenance: Provenance { events: vec![] },
parser_version: kebab_core::ParserVersion("test-parser-0".into()),
schema_version: 1,
doc_version: 1,
}
}
fn doc_id() -> kebab_core::DocumentId {
kebab_core::DocumentId("d".repeat(32))
}
fn span(start: u32, end: u32) -> SourceSpan {
SourceSpan::Line { start, end }
}
fn common_for(
kind: &str,
heading_path: &[String],
ordinal: u32,
s: SourceSpan,
) -> CommonBlock {
CommonBlock {
block_id: id_for_block(&doc_id(), kind, heading_path, ordinal, &s),
heading_path: heading_path.to_vec(),
source_span: s,
}
}
fn heading(level: u8, text: &str, ordinal: u32, line: u32) -> Block {
Block::Heading(HeadingBlock {
common: common_for("heading", &[], ordinal, span(line, line)),
level,
text: text.into(),
})
}
/// Heading variant that carries a parent path — kb-normalize stamps
/// every block under `# Alpha` with `heading_path = []` for the H1
/// itself but `["Alpha"]` for the H2 that follows. Tests covering
/// the heading-only chunk path (I2) need that asymmetry.
fn heading_with_parents(
level: u8,
text: &str,
parents: &[&str],
ordinal: u32,
line: u32,
) -> Block {
let hp: Vec<String> = parents.iter().map(|s| (*s).into()).collect();
Block::Heading(HeadingBlock {
common: common_for("heading", &hp, ordinal, span(line, line)),
level,
text: text.into(),
})
}
fn paragraph(
text: &str,
heading_path: &[&str],
ordinal: u32,
line: u32,
) -> Block {
let hp: Vec<String> = heading_path.iter().map(|s| (*s).into()).collect();
Block::Paragraph(TextBlock {
common: common_for("paragraph", &hp, ordinal, span(line, line)),
text: text.into(),
inlines: vec![],
})
}
fn code_block(
code: &str,
heading_path: &[&str],
ordinal: u32,
s: SourceSpan,
) -> Block {
let hp: Vec<String> = heading_path.iter().map(|s| (*s).into()).collect();
Block::Code(CodeBlock {
common: common_for("code", &hp, ordinal, s),
lang: Some("rust".into()),
code: code.into(),
})
}
fn table(
headers: Vec<&str>,
rows: Vec<Vec<&str>>,
heading_path: &[&str],
ordinal: u32,
s: SourceSpan,
) -> Block {
let hp: Vec<String> = heading_path.iter().map(|s| (*s).into()).collect();
Block::Table(TableBlock {
common: common_for("table", &hp, ordinal, s),
headers: headers.into_iter().map(String::from).collect(),
rows: rows
.into_iter()
.map(|r| r.into_iter().map(String::from).collect())
.collect(),
})
}
fn image_ref(
alt: &str,
heading_path: &[&str],
ordinal: u32,
line: u32,
) -> Block {
let hp: Vec<String> = heading_path.iter().map(|s| (*s).into()).collect();
Block::ImageRef(ImageRefBlock {
common: common_for("imageref", &hp, ordinal, span(line, line)),
asset_id: None,
src: "img.png".into(),
alt: alt.into(),
ocr: None,
caption: None,
})
}
fn default_policy(target: usize, overlap: usize) -> ChunkPolicy {
ChunkPolicy {
target_tokens: target,
overlap_tokens: overlap,
respect_markdown_headings: true,
chunker_version: ChunkerVersion(VERSION_LABEL.into()),
}
}
#[test]
fn chunker_version_is_md_heading_v1() {
assert_eq!(
MdHeadingV1Chunker.chunker_version(),
ChunkerVersion(VERSION_LABEL.to_string())
);
}
#[test]
fn policy_hash_is_deterministic_and_16_hex() {
let p = default_policy(500, 80);
let h1 = MdHeadingV1Chunker.policy_hash(&p);
let h2 = MdHeadingV1Chunker.policy_hash(&p);
assert_eq!(h1, h2);
assert_eq!(h1.len(), POLICY_HASH_HEX_LEN);
assert!(h1.bytes().all(|b| b.is_ascii_hexdigit()));
}
#[test]
fn policy_hash_differs_when_policy_differs() {
let p1 = default_policy(500, 80);
let p2 = default_policy(500, 0);
assert_ne!(
MdHeadingV1Chunker.policy_hash(&p1),
MdHeadingV1Chunker.policy_hash(&p2)
);
}
/// Heading boundary respected: two H2 sections produce separate
/// chunks; no chunk's block_ids straddle the H2→H2 boundary.
#[test]
fn heading_boundary_respected() {
let blocks = vec![
heading(2, "First", 0, 1),
paragraph("body of first", &["First"], 0, 2),
heading(2, "Second", 1, 3),
paragraph("body of second", &["Second"], 0, 4),
];
let doc = make_doc(blocks);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(10_000, 0))
.unwrap();
assert_eq!(chunks.len(), 2);
// First chunk = (heading "First", paragraph)
assert_eq!(chunks[0].block_ids.len(), 2);
// Second chunk = (heading "Second", paragraph)
assert_eq!(chunks[1].block_ids.len(), 2);
// heading_path on chunk 0 belongs to "First" section.
assert_eq!(chunks[0].heading_path, vec!["First".to_string()]);
assert_eq!(chunks[1].heading_path, vec!["Second".to_string()]);
}
/// A code block of ~800 tokens (≈2400 bytes) stays in a single
/// chunk even when target=500.
#[test]
fn code_block_never_splits() {
// 2400 bytes ≈ 800 tokens at BYTES_PER_TOKEN=3.
let big = "x".repeat(2400);
let blocks = vec![code_block(&big, &[], 0, span(1, 50))];
let doc = make_doc(blocks);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(500, 80))
.unwrap();
assert_eq!(chunks.len(), 1);
assert_eq!(chunks[0].block_ids.len(), 1);
assert!(chunks[0].token_estimate > 500);
}
/// A table of size < 2× target stays in a single chunk.
#[test]
fn table_stays_single_chunk_when_small() {
let t = table(
vec!["a", "b", "c"],
vec![vec!["1", "2", "3"], vec!["4", "5", "6"]],
&[],
0,
span(1, 4),
);
let blocks = vec![t];
let doc = make_doc(blocks);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(500, 80))
.unwrap();
assert_eq!(chunks.len(), 1);
assert_eq!(chunks[0].block_ids.len(), 1);
}
/// A long sequence of paragraphs splits at target_tokens with
/// overlap_tokens worth of seeded paragraph from the prior chunk.
#[test]
fn long_section_splits_with_overlap() {
// Each paragraph is 60 bytes ≈ 20 tokens. target=50, overlap=20
// → after ~3 paragraphs we hit the target; the next chunk
// starts seeded with one paragraph from the prior tail.
let mut bs = vec![heading(2, "Long", 0, 1)];
for i in 0..6u32 {
bs.push(paragraph(&"x".repeat(60), &["Long"], i, i + 2));
}
let doc = make_doc(bs);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(50, 20))
.unwrap();
assert!(
chunks.len() >= 2,
"expected ≥2 chunks, got {}: {chunks:#?}",
chunks.len()
);
// Every chunk lives under the same heading_path "Long".
for c in &chunks {
assert_eq!(c.heading_path, vec!["Long".to_string()]);
}
// Overlap propagates: the last block_id of chunk N appears in
// chunk N+1's block_ids (paragraph-level overlap rule).
for w in chunks.windows(2) {
let prev_tail = w[0].block_ids.last().unwrap();
assert!(
w[1].block_ids.contains(prev_tail),
"chunk N+1 must seed from chunk N's tail; \
prev_tail={prev_tail:?}, next ids={:?}",
w[1].block_ids
);
}
}
/// ImageRef → own chunk, token_estimate=0.
#[test]
fn image_ref_emits_own_chunk_zero_tokens() {
let blocks = vec![
heading(2, "With image", 0, 1),
paragraph("intro", &["With image"], 0, 2),
image_ref("a cat", &["With image"], 0, 3),
paragraph("after", &["With image"], 1, 4),
];
let doc = make_doc(blocks);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(10_000, 0))
.unwrap();
// Expect: (heading + intro), (image), (after). The image must
// be its own chunk and carry token_estimate=0.
assert!(chunks.len() >= 3, "unexpected chunk count: {chunks:#?}");
let img_chunk = chunks
.iter()
.find(|c| c.text == "a cat")
.expect("image chunk present");
assert_eq!(img_chunk.token_estimate, 0);
assert_eq!(img_chunk.block_ids.len(), 1);
}
/// Identical input + identical policy → identical chunk_ids over
/// 1000 iterations.
#[test]
fn deterministic_chunk_ids_1000() {
let blocks = vec![
heading(2, "Det", 0, 1),
paragraph("body 1", &["Det"], 0, 2),
paragraph("body 2", &["Det"], 1, 3),
heading(2, "Det 2", 1, 4),
paragraph("body 3", &["Det 2"], 0, 5),
];
let doc = make_doc(blocks);
let policy = default_policy(50, 10);
let baseline: Vec<String> = MdHeadingV1Chunker
.chunk(&doc, &policy)
.unwrap()
.into_iter()
.map(|c| c.chunk_id.0)
.collect();
for _ in 0..1000 {
let again: Vec<String> = MdHeadingV1Chunker
.chunk(&doc, &policy)
.unwrap()
.into_iter()
.map(|c| c.chunk_id.0)
.collect();
assert_eq!(again, baseline);
}
}
/// I2 regression: when a Heading is followed immediately by another
/// Heading or atomic block (no intervening prose), the resulting
/// heading-only / heading-led chunk must carry the heading text in
/// its own `heading_path`. Pattern: `# Alpha`, `## Beta`, code.
///
/// Before the fix, chunk[0] (Heading-only "Alpha") would have
/// `heading_path = []` because `kb-normalize` does not stamp a
/// heading inside its own path; the chunker fell back to the
/// heading's parent path. After the fix it is `["Alpha"]`.
///
/// `chunk_id` recipe (`doc_id, chunker_version, block_ids,
/// policy_hash`) does NOT include `heading_path`, so this fix does
/// NOT shift chunk_ids — only `heading_path` fields.
#[test]
fn heading_only_chunk_carries_self_in_path() {
// # Alpha (H1, no parents)
// ## Beta (H2, parent = ["Alpha"])
// ```rust ... ``` (code, heading_path = ["Alpha", "Beta"])
let blocks = vec![
heading_with_parents(1, "Alpha", &[], 0, 1),
heading_with_parents(2, "Beta", &["Alpha"], 0, 2),
code_block("fn x() {}", &["Alpha", "Beta"], 0, span(3, 3)),
];
let doc = make_doc(blocks);
let chunks = MdHeadingV1Chunker
.chunk(&doc, &default_policy(10_000, 0))
.unwrap();
// Three chunks: Heading-only Alpha, Heading-only Beta, code.
assert_eq!(chunks.len(), 3, "got {chunks:#?}");
assert_eq!(chunks[0].heading_path, vec!["Alpha".to_string()]);
assert_eq!(
chunks[1].heading_path,
vec!["Alpha".to_string(), "Beta".to_string()]
);
assert_eq!(
chunks[2].heading_path,
vec!["Alpha".to_string(), "Beta".to_string()]
);
}
/// I3 regression: a pathological policy with
/// `overlap_tokens >= target_tokens` must NOT degenerate into
/// 1-block-per-chunk. The seed budget is clamped to `target/2`,
/// guaranteeing every flushed chunk has space for fresh content.
#[test]
fn overlap_clamped_when_overlap_exceeds_target() {
// 5 paragraphs of ~20 tokens each (60 bytes / 3 BPT).
// target = 50, overlap = 200 (4× target → would trip flush
// immediately without clamp).
let mut bs = vec![heading_with_parents(2, "Long", &[], 0, 1)];
for i in 0..5u32 {
bs.push(paragraph(&"x".repeat(60), &["Long"], i, i + 2));
}
let doc = make_doc(bs);
let policy = ChunkPolicy {
target_tokens: 50,
overlap_tokens: 200,
respect_markdown_headings: true,
chunker_version: ChunkerVersion(VERSION_LABEL.into()),
};
let chunks = MdHeadingV1Chunker.chunk(&doc, &policy).unwrap();
// Without the clamp, every chunk after the first would have
// exactly 1 paragraph (because seed alone already exceeds
// target and acc.has_non_heading_content() is true the moment
// any seed lands). With the clamp, follow-on chunks must hold
// at least the seed paragraph + the new paragraph = ≥2 blocks.
for (i, c) in chunks.iter().enumerate() {
// The very first chunk includes the heading + first para
// (no seed), so it is also ≥2. Subsequent chunks must be
// seed+new ≥ 2.
assert!(
c.block_ids.len() >= 2,
"chunk {i} degenerated to {} block(s); pathology not \
prevented: {chunks:#?}",
c.block_ids.len()
);
}
}
}