The indent trigger was using .abs() which fired on both increased indent
(non-indented → indented) AND decreased indent (indented → non-indented).
This caused drop-cap style paragraphs (indented first line, flush-left
continuation) to incorrectly split into two blocks.
Per plan Phase 4.4 heuristic #2, indent change should only trigger when the
current line is MORE indented (to the right, larger x0) than the block
average - i.e., a new paragraph starting after non-indented text. It should
NOT trigger for decreased indent (first line indented, rest flush-left).
Fix: Remove .abs() and only check if line_x0 - block_avg_x0 > threshold.
Tests:
- test_indented_first_line_new_block: PASS (non-indented → indented splits)
- test_indented_first_line_of_paragraph_not_split: PASS (drop cap stays together)
- All 179 line module tests: PASS
Add supply chain security gates:
- cargo-deny.toml: License allowlist (MIT, Apache-2.0, BSD, ISC, Zlib,
Unicode-DFS-2016, MPL-2.0), bans (openssl-sys, native-tls, git2,
libgit2-sys), minimum versions (ring >= 0.17.5, rustls >= 0.23)
- build/CHECKSUMS.sha256: SHA-256 checksum for build/glyph-shapes.json.
build.rs already verifies checksums on every build (TH-06 supply-chain
gate per plan line 909)
These are part of the security hardening epic (pdftract-e9lz).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Add cargo xtask gen-shape-db command that walks font directories,
rasterizes glyphs at 32x32 via fontdue, computes pHash, and outputs
build/glyph-shapes.json.
Implementation details:
- Fontdue integration for TrueType/OpenType font loading
- 32x32 bitmap rasterization with centering
- DCT-based pHash computation (32x32 DCT → 8x8 low-freq → median threshold)
- Character frequency data for collision resolution
- Deduplication by (phash, char) pairs
- Cross-character collision handling (keep higher-frequency char)
- Sorted output by pHash ascending
Artifacts:
- build/frequency.json: Character frequency rankings
- build/README.md: Command documentation and usage
Acceptance criteria:
- ✅ cargo xtask gen-shape-db --fonts <dir> produces valid JSON
- ✅ Deterministic output (byte-identical on same inputs)
- ✅ Fontdue integration and 32x32 rasterization
- ✅ pHash computation via DCT
- ⚠️ No system fonts for full integration test (documented)
Closes: pdftract-2aq0
