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Author	SHA1	Message	Date
andodeki	a82c8f7ff7	feat(pdf): Unicode-aware search and layout-aware reading order ... Phase 8 bullets one and two. Probing the existing code first, as the workflow requires, found five defects rather than the one the plan names: SPLIT MATCH 'Hello': 0 hits plain_text: "Hello" PRECOMPOSED 'café': 0 hits COLUMNS plain_text: "LeftTopRightTop\nLeftBotRightBot" OUT OF ORDER plain_text: "second\nfirst" `PageText::find` searched one run at a time and documented that as a known limitation. It is a limitation from inside the code and a broken feature from outside it: a writer starts a new run wherever it adjusts kerning, so an ordinary word arrives as two runs, and the find bar says a word plainly visible on the page is not there. `search.rs` indexes the page as one flattened string with a map back to (run, character), so a cross-run match is found and highlighted with one rectangle per run — never a merged box, which across a line break covers half the paragraph. The separator between two runs is a geometric question with three answers: abutting runs join with nothing (one word, split by kerning), separated runs with a space, and a different line or column with a newline. The newline matters as much as the empty join: joining lines with a space lets "one Right" match across a column gutter, text that appears nowhere. Whether two runs share a column is *asked* of the layout analysis rather than re-derived, or the extracted text and the searched text disagree about where a column ends — the original defect wearing a different hat. NFD, never NFC: composition needs the next character, so an NFC fold applied per character composes nothing and the two spellings of an accent stay different. That was a real bug in the first draft. And case *folding*, not lowercasing — Rust lowercases ß to ß, so "Strasse" never found "Straße". Columns are detected before lines, because two columns share their baselines; that is what makes them columns. Bands are separated by a gutter rather than by bare non-overlap, since two abutting runs on a line do not overlap either. Also fixed, found by running the gates rather than by looking: a stream reader trimmed a trailing CR before `endstream` as if it were the writer's separator. Binary data ends in CR about one time in 256, and when it did the reader returned a stream one byte short — no longer AES-block-aligned, so decryption produced garbage and Flate failed. Roughly one encrypted document in 250 was silently corrupt on read. The test failed once under coverage, passed five times in isolation, and failed 2 in 40 when actually counted. A /Length consistent with the file is now the authority; both stream readers are fixed and a test reads one file through each. 1477 tests pass (was 1426), coverage 88.37%, all floors met, external readers pass. 10 mutations across the two modules, all killed. ADR 0034.	2026-08-19 16:12:12 +00:00