From 1379bc62e247a13b4e0549b8019f73ab8900309b Mon Sep 17 00:00:00 2001
From: jedarden <github@jedarden.com>
Date: Sun, 5 Jul 2026 19:27:28 -0400
Subject: [PATCH] docs(bf-fyfbf): document truncated-flate test file findings

The file test_truncated_flate_recovery.rs does not exist.
Documented related test files and fixture patterns.
Identified that test_truncated_mid_stream() in error_recovery_integration.rs
is the closest existing test for truncated stream handling.

Acceptance criteria:
- Test file located: NOT FOUND (file does not exist)
- Related test structures: DOCUMENTED
- Existing test functions: LISTED
---
 notes/bf-fyfbf.md | 68 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 notes/bf-fyfbf.md

diff --git a/notes/bf-fyfbf.md b/notes/bf-fyfbf.md
new file mode 100644
index 0000000..7d105bc
--- /dev/null
+++ b/notes/bf-fyfbf.md
@@ -0,0 +1,68 @@
+# Bead bf-fyfbf: Locate and read truncated-flate test file
+
+## Summary
+
+The test file `crates/pdftract-core/tests/test_truncated_flate_recovery.rs` **does not exist**.
+
+## What was found
+
+### Related test files that DO exist:
+
+1. **`crates/pdftract-core/tests/error_recovery_integration.rs`**
+   - Contains `test_truncated_mid_stream()` function (line 165)
+   - Tests truncated streams with expected `STREAM_DECODE_ERROR` diagnostics
+   - Uses `tests/error_recovery/fixtures/truncated_mid_stream.pdf`
+
+2. **`crates/pdftract-core/tests/stream_decoder_fixtures.rs`**
+   - Contains `flate_truncated` fixture test (line 61-65)
+   - Tests flate decoder with truncated input
+   - Uses `tests/stream_decoder/fixtures/flate_truncated.bin`
+
+### Fixture files that exist:
+
+1. **`tests/fixtures/malformed/truncated-flate.pdf`** (588 bytes)
+   - This appears to be the PDF fixture that `test_truncated_flate_recovery.rs` would test
+   - Not currently referenced by any existing test
+
+2. **`tests/stream_decoder/fixtures/flate_truncated.bin`**
+   - Binary fixture for stream decoder testing
+   - Has `.meta` file: "FlateDecode: mid-stream EOF; expects partial bytes + STREAM_DECODE_ERROR"
+   - Has `.expected` file (1 line, minimal output)
+
+## Basic test structure understanding
+
+From examining `error_recovery_integration.rs` and `stream_decoder_fixtures.rs`:
+
+1. **Error recovery test pattern:**
+   - Load fixture with `fs::read()`
+   - Run extraction under `catch_unwind` for panic safety
+   - Verify PDF starts with `%PDF-`
+   - Check for expected diagnostics
+
+2. **Stream decoder test pattern:**
+   - Define fixture metadata (filter name, expected diagnostics, bomb limits)
+   - Load binary fixture
+   - Decode through appropriate decoder
+   - Compare against `.expected` file
+
+## Existing test functions documented
+
+### error_recovery_integration.rs:
+- `test_xref_30pct_bad_offsets()`
+- `test_missing_mediabox_all_pages()`
+- `test_missing_endobj()`
+- `test_truncated_mid_stream()` - most relevant
+- `test_int_overflow_bbox()`
+- `test_nested_failure()`
+- `test_combined_failures()`
+- `test_inv_8_no_panics_across_all_fixtures()`
+
+### stream_decoder_fixtures.rs:
+- `test_all_stream_decoder_fixtures()` - includes flate_truncated
+- `test_each_filter_exercised()`
+
+## Conclusion
+
+The file `test_truncated_flate_recovery.rs` does not exist and needs to be created. The parent bead `bf-4g6dj` assumes this file exists, but it appears this is a new test file that should be created to test the specific `truncated-flate.pdf` fixture.
+
+The test file should likely follow the pattern from `error_recovery_integration.rs` but specifically for testing the `truncated-flate.pdf` fixture and validating its extraction results and error diagnostics.