Phase 6a: extract frontmatter.py from merge.py — pure YAML helpers

4 functions + 2 constants extracted to lib/frontmatter.py:
- parse_yaml_frontmatter, union_edge_lists, serialize_edge_fields,
  serialize_frontmatter, REWEAVE_EDGE_FIELDS, RECIPROCAL_EDGE_MAP

merge.py: 1678 → 1562 lines (−116).
test_reweave_merge.py: replaced local function copies with imports from
frontmatter.py — fixes missing challenged_by in test's REWEAVE_EDGE_FIELDS.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
m3taversal 2026-04-16 13:16:38 +01:00
parent 53dc18afd5
commit ed1edd6466
3 changed files with 192 additions and 251 deletions

133
lib/frontmatter.py Normal file
View file

@ -0,0 +1,133 @@
"""Pure YAML frontmatter parsing and serialization for claim/entity files.
Shared by merge (reweave merge, reciprocal edges) and reweave scripts.
All functions are pure zero I/O, zero async, zero DB.
Extracted from merge.py Phase 6 of decomposition (Ganymede-approved plan).
"""
import yaml
# Edge field names recognized in claim frontmatter.
# Order matters: serialize_edge_fields writes them in this order when appending new fields.
REWEAVE_EDGE_FIELDS = ("supports", "challenges", "challenged_by", "depends_on", "related", "reweave_edges")
# Reciprocal edge mapping: when A has edge_type → B, B gets reciprocal → A.
# When A supports B, B also supports A (approximately symmetric).
# When A challenges B, B is challenged_by A (NOT symmetric — direction matters).
RECIPROCAL_EDGE_MAP = {
"supports": "supports",
"challenges": "challenged_by",
"related": "related",
"depends_on": "related", # A depends_on B → B is related to A (not symmetric)
}
def parse_yaml_frontmatter(text: str) -> tuple[dict | None, str, str]:
"""Parse YAML frontmatter from markdown text.
Returns (frontmatter_dict, raw_fm_text, body_text_including_closing_delimiter).
Returns (None, "", text) if no valid frontmatter found.
raw_fm_text is the text between the --- delimiters (no delimiters, no leading newline).
"""
if not text.startswith("---"):
return None, "", text
end = text.find("\n---", 3)
if end == -1:
return None, "", text
try:
raw_fm_text = text[4:end] # skip "---\n", stop before "\n---"
fm = yaml.safe_load(raw_fm_text)
body = text[end:] # includes closing \n--- and body
return (fm if isinstance(fm, dict) else None), raw_fm_text, body
except Exception:
return None, "", text
def union_edge_lists(main_edges: list, branch_edges: list) -> list:
"""Union two edge lists, preserving order from main (append new at end).
Deduplicates by lowercase slug. Main's order is preserved; branch-only
edges are appended in their original order.
"""
seen = set()
result = []
for edge in main_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
for edge in branch_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
return result
def serialize_edge_fields(raw_fm_text: str, merged_edges: dict[str, list]) -> str:
"""Splice merged edge fields into raw frontmatter text, preserving all other fields byte-identical.
Only modifies REWEAVE_EDGE_FIELDS lines. All other frontmatter (title, confidence, type, etc.)
stays exactly as it was in the source text no yaml.dump reformatting.
Args:
raw_fm_text: The raw YAML text between the --- delimiters (no delimiters included).
merged_edges: {field_name: [edge_values]} for each edge field that should be present.
"""
lines = raw_fm_text.split("\n")
result_lines = []
i = 0
fields_written = set()
while i < len(lines):
line = lines[i]
# Check if this line starts an edge field
matched_field = None
for field in REWEAVE_EDGE_FIELDS:
if line.startswith(f"{field}:"):
matched_field = field
break
if matched_field:
fields_written.add(matched_field)
# Skip the old field and its list items (may be indented with spaces)
i += 1
while i < len(lines) and lines[i] and (lines[i][0] in (' ', '-')):
i += 1
# Write the merged version
edges = merged_edges.get(matched_field, [])
if edges:
result_lines.append(f"{matched_field}:")
for edge in edges:
result_lines.append(f"- {edge}")
# Don't increment i — it's already past the old field
continue
else:
result_lines.append(line)
i += 1
# Append any new edge fields that didn't exist in the original
for field in REWEAVE_EDGE_FIELDS:
if field not in fields_written:
edges = merged_edges.get(field, [])
if edges:
result_lines.append(f"{field}:")
for edge in edges:
result_lines.append(f"- {edge}")
return "\n".join(result_lines)
def serialize_frontmatter(raw_fm_text: str, merged_edges: dict[str, list], body: str) -> str:
"""Rebuild markdown file: splice merged edges into raw frontmatter, append body.
Uses string-level surgery only edge fields are modified. All other frontmatter
stays byte-identical to the source. No yaml.dump reformatting.
"""
spliced = serialize_edge_fields(raw_fm_text, merged_edges)
# body starts with \n--- (closing delimiter + body text)
if body.startswith("\n"):
return f"---\n{spliced}{body}"
return f"---\n{spliced}\n{body}"

View file

@ -411,130 +411,14 @@ async def _cherry_pick_onto_main(branch: str) -> tuple[bool, str]:
await _git("branch", "-D", clean_branch)
REWEAVE_EDGE_FIELDS = ("supports", "challenges", "challenged_by", "depends_on", "related", "reweave_edges")
# When A supports B, B also supports A (approximately symmetric).
# When A challenges B, B is challenged_by A (NOT symmetric — direction matters).
RECIPROCAL_EDGE_MAP = {
"supports": "supports",
"challenges": "challenged_by",
"related": "related",
"depends_on": "related", # A depends_on B → B is related to A (not symmetric)
}
def _parse_yaml_frontmatter(text: str) -> tuple[dict | None, str, str]:
"""Parse YAML frontmatter from markdown text.
Returns (frontmatter_dict, raw_fm_text, body_text_including_closing_delimiter).
Returns (None, "", text) if no valid frontmatter found.
raw_fm_text is the text between the --- delimiters (no delimiters, no leading newline).
"""
import yaml
if not text.startswith("---"):
return None, "", text
end = text.find("\n---", 3)
if end == -1:
return None, "", text
try:
raw_fm_text = text[4:end] # skip "---\n", stop before "\n---"
fm = yaml.safe_load(raw_fm_text)
body = text[end:] # includes closing \n--- and body
return (fm if isinstance(fm, dict) else None), raw_fm_text, body
except Exception:
return None, "", text
def _union_edge_lists(main_edges: list, branch_edges: list) -> list:
"""Union two edge lists, preserving order from main (append new at end).
Deduplicates by lowercase slug. Main's order is preserved; branch-only
edges are appended in their original order.
"""
seen = set()
result = []
for edge in main_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
for edge in branch_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
return result
def _serialize_edge_fields(raw_fm_text: str, merged_edges: dict[str, list]) -> str:
"""Splice merged edge fields into raw frontmatter text, preserving all other fields byte-identical.
Only modifies REWEAVE_EDGE_FIELDS lines. All other frontmatter (title, confidence, type, etc.)
stays exactly as it was in the source text no yaml.dump reformatting.
Args:
raw_fm_text: The raw YAML text between the --- delimiters (no delimiters included).
merged_edges: {field_name: [edge_values]} for each edge field that should be present.
"""
import re
import yaml
lines = raw_fm_text.split("\n")
result_lines = []
i = 0
fields_written = set()
while i < len(lines):
line = lines[i]
# Check if this line starts an edge field
matched_field = None
for field in REWEAVE_EDGE_FIELDS:
if line.startswith(f"{field}:"):
matched_field = field
break
if matched_field:
fields_written.add(matched_field)
# Skip the old field and its list items (may be indented with spaces)
i += 1
while i < len(lines) and lines[i] and (lines[i][0] in (' ', '-')):
i += 1
# Write the merged version
edges = merged_edges.get(matched_field, [])
if edges:
result_lines.append(f"{matched_field}:")
for edge in edges:
result_lines.append(f"- {edge}")
# Don't increment i — it's already past the old field
continue
else:
result_lines.append(line)
i += 1
# Append any new edge fields that didn't exist in the original
for field in REWEAVE_EDGE_FIELDS:
if field not in fields_written:
edges = merged_edges.get(field, [])
if edges:
result_lines.append(f"{field}:")
for edge in edges:
result_lines.append(f"- {edge}")
return "\n".join(result_lines)
def _serialize_frontmatter(raw_fm_text: str, merged_edges: dict[str, list], body: str) -> str:
"""Rebuild markdown file: splice merged edges into raw frontmatter, append body.
Uses string-level surgery only edge fields are modified. All other frontmatter
stays byte-identical to the source. No yaml.dump reformatting.
"""
spliced = _serialize_edge_fields(raw_fm_text, merged_edges)
# body starts with \n--- (closing delimiter + body text)
if body.startswith("\n"):
return f"---\n{spliced}{body}"
return f"---\n{spliced}\n{body}"
from .frontmatter import (
REWEAVE_EDGE_FIELDS,
RECIPROCAL_EDGE_MAP,
parse_yaml_frontmatter,
union_edge_lists,
serialize_edge_fields,
serialize_frontmatter,
)
async def _merge_reweave_pr(branch: str) -> tuple[bool, str]:
@ -605,8 +489,8 @@ async def _merge_reweave_pr(branch: str) -> tuple[bool, str]:
continue
# Parse frontmatter from both versions
main_fm, main_raw_fm, main_body = _parse_yaml_frontmatter(main_content)
branch_fm, _branch_raw_fm, branch_body = _parse_yaml_frontmatter(branch_content)
main_fm, main_raw_fm, main_body = parse_yaml_frontmatter(main_content)
branch_fm, _branch_raw_fm, branch_body = parse_yaml_frontmatter(branch_content)
if main_fm is None or branch_fm is None:
# Parse failure = something unexpected. Fail the merge, don't fallback
@ -638,13 +522,13 @@ async def _merge_reweave_pr(branch: str) -> tuple[bool, str]:
# Collect merged edges for string-level splicing
if main_list or branch_list:
merged_edges[field] = _union_edge_lists(main_list, branch_list)
merged_edges[field] = union_edge_lists(main_list, branch_list)
# Write merged file — splice edges into main's raw frontmatter, use main's body
full_path = os.path.join(worktree_path, fpath)
os.makedirs(os.path.dirname(full_path), exist_ok=True)
with open(full_path, "w") as f:
f.write(_serialize_frontmatter(main_raw_fm, merged_edges, main_body))
f.write(serialize_frontmatter(main_raw_fm, merged_edges, main_body))
await _git("add", fpath, cwd=worktree_path)
merged_count += 1
@ -950,7 +834,7 @@ async def _reciprocal_edges(main_sha: str, branch_sha: str):
except Exception:
continue
fm, raw_fm, body = _parse_yaml_frontmatter(content)
fm, raw_fm, body = parse_yaml_frontmatter(content)
if fm is None:
continue
@ -1031,7 +915,7 @@ def _add_edge_to_file(file_path, edge_type: str, target_slug: str) -> bool:
except Exception:
return False
fm, raw_fm, body = _parse_yaml_frontmatter(content)
fm, raw_fm, body = parse_yaml_frontmatter(content)
if fm is None:
return False
@ -1058,7 +942,7 @@ def _add_edge_to_file(file_path, edge_type: str, target_slug: str) -> bool:
merged_edges.setdefault(edge_type, []).append(target_slug)
# Serialize using the same string-surgery approach as reweave
new_fm = _serialize_edge_fields(raw_fm, merged_edges)
new_fm = serialize_edge_fields(raw_fm, merged_edges)
if body.startswith("\n"):
new_content = f"---\n{new_fm}{body}"
else:

View file

@ -1,102 +1,26 @@
"""Tests for _merge_reweave_pr helpers — frontmatter union, order-preserving dedup, string-level splicing.
"""Tests for frontmatter helpers — frontmatter union, order-preserving dedup, string-level splicing.
These test the pure functions used by _merge_reweave_pr in lib/merge.py.
Copied here because lib/merge.py's relative imports make direct import impractical in tests.
If these functions change in merge.py, update them here too.
These test the pure functions in lib/frontmatter.py (extracted from merge.py Phase 6).
"""
import sys
import os
import pytest
import yaml
# --- Copied from lib/merge.py (pure functions, no dependencies) ---
REWEAVE_EDGE_FIELDS = ("supports", "challenges", "depends_on", "related", "reweave_edges")
def _parse_yaml_frontmatter(text: str) -> tuple[dict | None, str, str]:
if not text.startswith("---"):
return None, "", text
end = text.find("\n---", 3)
if end == -1:
return None, "", text
try:
raw_fm_text = text[4:end]
fm = yaml.safe_load(raw_fm_text)
body = text[end:]
return (fm if isinstance(fm, dict) else None), raw_fm_text, body
except Exception:
return None, "", text
def _union_edge_lists(main_edges: list, branch_edges: list) -> list:
seen = set()
result = []
for edge in main_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
for edge in branch_edges:
key = str(edge).strip().lower()
if key not in seen:
seen.add(key)
result.append(edge)
return result
def _serialize_edge_fields(raw_fm_text: str, merged_edges: dict[str, list]) -> str:
lines = raw_fm_text.split("\n")
result_lines = []
i = 0
fields_written = set()
while i < len(lines):
line = lines[i]
matched_field = None
for field in REWEAVE_EDGE_FIELDS:
if line.startswith(f"{field}:"):
matched_field = field
break
if matched_field:
fields_written.add(matched_field)
i += 1
while i < len(lines) and lines[i] and (lines[i][0] in (' ', '-')):
i += 1
edges = merged_edges.get(matched_field, [])
if edges:
result_lines.append(f"{matched_field}:")
for edge in edges:
result_lines.append(f"- {edge}")
continue
else:
result_lines.append(line)
i += 1
for field in REWEAVE_EDGE_FIELDS:
if field not in fields_written:
edges = merged_edges.get(field, [])
if edges:
result_lines.append(f"{field}:")
for edge in edges:
result_lines.append(f"- {edge}")
return "\n".join(result_lines)
def _serialize_frontmatter(raw_fm_text: str, merged_edges: dict[str, list], body: str) -> str:
spliced = _serialize_edge_fields(raw_fm_text, merged_edges)
if body.startswith("\n"):
return f"---\n{spliced}{body}"
return f"---\n{spliced}\n{body}"
# --- End copied functions ---
sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "lib"))
from frontmatter import (
REWEAVE_EDGE_FIELDS,
parse_yaml_frontmatter,
union_edge_lists,
serialize_edge_fields,
serialize_frontmatter,
)
class TestParseYamlFrontmatter:
def test_basic(self):
text = "---\ntitle: Test Claim\nsupports:\n- claim-a\n---\nBody text here."
fm, raw, body = _parse_yaml_frontmatter(text)
fm, raw, body = parse_yaml_frontmatter(text)
assert fm is not None
assert fm["title"] == "Test Claim"
assert fm["supports"] == ["claim-a"]
@ -105,14 +29,14 @@ class TestParseYamlFrontmatter:
def test_no_frontmatter(self):
text = "Just plain text"
fm, raw, body = _parse_yaml_frontmatter(text)
fm, raw, body = parse_yaml_frontmatter(text)
assert fm is None
assert raw == ""
assert body == text
def test_malformed_yaml(self):
text = "---\n: invalid: yaml: {{{\n---\nBody"
fm, raw, body = _parse_yaml_frontmatter(text)
fm, raw, body = parse_yaml_frontmatter(text)
assert fm is None
@ -120,38 +44,38 @@ class TestUnionEdgeLists:
def test_no_overlap(self):
main = ["claim-a", "claim-b"]
branch = ["claim-c", "claim-d"]
result = _union_edge_lists(main, branch)
result = union_edge_lists(main, branch)
assert result == ["claim-a", "claim-b", "claim-c", "claim-d"]
def test_overlap_preserves_main_order(self):
main = ["claim-b", "claim-a"]
branch = ["claim-a", "claim-c"]
result = _union_edge_lists(main, branch)
result = union_edge_lists(main, branch)
assert result == ["claim-b", "claim-a", "claim-c"]
def test_case_insensitive_dedup(self):
main = ["Claim A"]
branch = ["claim a", "Claim B"]
result = _union_edge_lists(main, branch)
result = union_edge_lists(main, branch)
assert len(result) == 2
assert result[0] == "Claim A"
assert result[1] == "Claim B"
def test_empty_main(self):
result = _union_edge_lists([], ["claim-a", "claim-b"])
result = union_edge_lists([], ["claim-a", "claim-b"])
assert result == ["claim-a", "claim-b"]
def test_empty_branch(self):
result = _union_edge_lists(["claim-a"], [])
result = union_edge_lists(["claim-a"], [])
assert result == ["claim-a"]
def test_both_empty(self):
assert _union_edge_lists([], []) == []
assert union_edge_lists([], []) == []
def test_duplicates_within_branch(self):
main = ["claim-a"]
branch = ["claim-b", "claim-b"]
result = _union_edge_lists(main, branch)
result = union_edge_lists(main, branch)
assert result == ["claim-a", "claim-b"]
@ -159,7 +83,7 @@ class TestSerializeEdgeFields:
def test_replaces_existing_field(self):
raw = "title: Test\nsupports:\n- old-claim"
merged = {"supports": ["old-claim", "new-claim"]}
result = _serialize_edge_fields(raw, merged)
result = serialize_edge_fields(raw, merged)
assert "- old-claim" in result
assert "- new-claim" in result
assert "title: Test" in result
@ -167,7 +91,7 @@ class TestSerializeEdgeFields:
def test_preserves_non_edge_fields_exactly(self):
raw = "title: 'Quoted Title'\nconfidence: 0.85\ntype: claim"
merged = {"related": ["new-claim"]}
result = _serialize_edge_fields(raw, merged)
result = serialize_edge_fields(raw, merged)
assert "title: 'Quoted Title'" in result
assert "confidence: 0.85" in result
assert "type: claim" in result
@ -177,7 +101,7 @@ class TestSerializeEdgeFields:
def test_appends_new_field(self):
raw = "title: Test\ntype: claim"
merged = {"supports": ["claim-a"]}
result = _serialize_edge_fields(raw, merged)
result = serialize_edge_fields(raw, merged)
assert "title: Test" in result
assert "supports:" in result
assert "- claim-a" in result
@ -185,7 +109,7 @@ class TestSerializeEdgeFields:
def test_empty_edges_removes_field(self):
raw = "title: Test\nsupports:\n- old-claim\ntype: claim"
merged = {} # no edges to write
result = _serialize_edge_fields(raw, merged)
result = serialize_edge_fields(raw, merged)
assert "supports:" not in result
assert "title: Test" in result
assert "type: claim" in result
@ -193,7 +117,7 @@ class TestSerializeEdgeFields:
def test_multiple_edge_fields(self):
raw = "title: Test\nsupports:\n- a\nchallenges:\n- b"
merged = {"supports": ["a", "c"], "challenges": ["b", "d"]}
result = _serialize_edge_fields(raw, merged)
result = serialize_edge_fields(raw, merged)
lines = result.split("\n")
# supports and challenges both present with merged values
assert "- a" in result
@ -205,9 +129,9 @@ class TestSerializeEdgeFields:
class TestSerializeFrontmatter:
def test_roundtrip_preserves_formatting(self):
original = "---\ntitle: 'Quoted Title'\nconfidence: 0.85\nsupports:\n- claim-a\n---\nBody text here."
fm, raw, body = _parse_yaml_frontmatter(original)
fm, raw, body = parse_yaml_frontmatter(original)
merged_edges = {"supports": ["claim-a", "claim-b"]}
result = _serialize_frontmatter(raw, merged_edges, body)
result = serialize_frontmatter(raw, merged_edges, body)
# Non-edge fields preserved exactly
assert "title: 'Quoted Title'" in result
@ -223,9 +147,9 @@ class TestSerializeFrontmatter:
def test_no_blank_line_before_closing_delimiter(self):
"""Ganymede critical: no extra blank line compounds on repeat reweaves."""
original = "---\ntitle: Test\nsupports:\n- a\n---\nBody."
fm, raw, body = _parse_yaml_frontmatter(original)
fm, raw, body = parse_yaml_frontmatter(original)
merged_edges = {"supports": ["a", "b"]}
result = _serialize_frontmatter(raw, merged_edges, body)
result = serialize_frontmatter(raw, merged_edges, body)
# Should NOT have \n\n--- (double newline before closing)
assert "\n\n---" not in result
@ -235,8 +159,8 @@ class TestSerializeFrontmatter:
merged_edges = {"supports": ["a", "b"]}
for _ in range(5):
fm, raw, body = _parse_yaml_frontmatter(text)
text = _serialize_frontmatter(raw, merged_edges, body)
fm, raw, body = parse_yaml_frontmatter(text)
text = serialize_frontmatter(raw, merged_edges, body)
assert text.count("\n\n") == 0 # no double newlines anywhere
@ -284,8 +208,8 @@ class TestFullUnionWorkflow:
"---\nBody text."
)
main_fm, main_raw, main_body = _parse_yaml_frontmatter(main_text)
branch_fm, _, _ = _parse_yaml_frontmatter(branch_text)
main_fm, main_raw, main_body = parse_yaml_frontmatter(main_text)
branch_fm, _, _ = parse_yaml_frontmatter(branch_text)
merged_edges = {}
for field in REWEAVE_EDGE_FIELDS:
@ -296,7 +220,7 @@ class TestFullUnionWorkflow:
if not isinstance(branch_list, list):
branch_list = [branch_list] if branch_list else []
if main_list or branch_list:
merged_edges[field] = _union_edge_lists(main_list, branch_list)
merged_edges[field] = union_edge_lists(main_list, branch_list)
assert merged_edges["supports"] == ["claim-a", "claim-b"]
assert "claim-x" in merged_edges["related"]
@ -304,7 +228,7 @@ class TestFullUnionWorkflow:
assert len(merged_edges.get("reweave_edges", [])) == 1
# Verify non-edge fields preserved in serialization
result = _serialize_frontmatter(main_raw, merged_edges, main_body)
result = serialize_frontmatter(main_raw, merged_edges, main_body)
assert "confidence: 0.8" in result
assert "title: Test Claim" in result
@ -313,8 +237,8 @@ class TestFullUnionWorkflow:
main_text = "---\ntitle: Original\nconfidence: 0.9\ntype: claim\n---\nBody."
branch_text = "---\ntitle: Original\nconfidence: 0.9\ntype: claim\nrelated:\n- new-claim\n---\nBody."
main_fm, main_raw, main_body = _parse_yaml_frontmatter(main_text)
branch_fm, _, _ = _parse_yaml_frontmatter(branch_text)
main_fm, main_raw, main_body = parse_yaml_frontmatter(main_text)
branch_fm, _, _ = parse_yaml_frontmatter(branch_text)
merged_edges = {}
for field in REWEAVE_EDGE_FIELDS:
@ -325,9 +249,9 @@ class TestFullUnionWorkflow:
if not isinstance(branch_list, list):
branch_list = [branch_list] if branch_list else []
if main_list or branch_list:
merged_edges[field] = _union_edge_lists(main_list, branch_list)
merged_edges[field] = union_edge_lists(main_list, branch_list)
result = _serialize_frontmatter(main_raw, merged_edges, main_body)
result = serialize_frontmatter(main_raw, merged_edges, main_body)
assert "title: Original" in result
assert "confidence: 0.9" in result
assert "type: claim" in result
@ -345,16 +269,16 @@ class TestFullUnionWorkflow:
if not isinstance(branch_list, list):
branch_list = [branch_list] if branch_list else []
result = _union_edge_lists(main_list, branch_list)
result = union_edge_lists(main_list, branch_list)
assert result == ["single-claim", "new-claim"]
def test_yaml_formatting_preserved_across_reweave(self):
"""The key test: non-edge YAML formatting stays byte-identical."""
# Use unusual but valid YAML formatting
main_text = "---\ntitle: 'A \"Quoted\" Title'\nconfidence: 0.85\nsome_custom_field: [1, 2, 3]\nsupports:\n- old-claim\n---\nBody."
fm, raw, body = _parse_yaml_frontmatter(main_text)
fm, raw, body = parse_yaml_frontmatter(main_text)
merged_edges = {"supports": ["old-claim", "new-claim"]}
result = _serialize_frontmatter(raw, merged_edges, body)
result = serialize_frontmatter(raw, merged_edges, body)
# These non-edge fields must be byte-identical to source
assert "title: 'A \"Quoted\" Title'" in result