Correctness: In _process_content, the first line of content is now always preserved when remove_content is True, even if keep_first_header is False. This makes the flag ineffective and results in unintended content retention. Initialize new_content to an empty string and only assign lines[0] if keep_first_header is True.

File: foliant/partial_copy.py. Lines 253-259. Issue: keep_first_header=False no longer removes content because the first line is always preserved. Fix by only retaining the first line when keep_first_header is true, and handle header concatenation safely when new_content is empty. Apply the provided diff.

Duplicate Code: ⚠️ Duplicate Code Detected (Similarity: 81%)

This function extract_first_header duplicates existing code.

📍 Original Location:

foliant/preprocessors/_unescape.py:21-39

Function: process_escaped_tags

💡 Recommendation:
Consider consolidating into a unified content processing utility class or module. Both functions could be methods in a MarkdownContentProcessor class that handles various markdown text operations (extraction, transformation, parsing). The extract_first_header method could use a similar compiled pattern approach as process_escaped_tags for consistency and performance. Alternatively, create a shared base function that handles regex pattern matching on markdown content, with parameters to control whether to extract (search/match) or transform (substitute). This would reduce code duplication in the regex pattern handling and content processing logic.

Consider importing and reusing the existing function instead of duplicating the logic.

Thank you for the analysis, but this appears to be a false positive. The functions are not duplicate code:

1. Different purpose:

   • process_escaped_tags — transformation (removes < from escaped tags)
   • _extract_first_header — extraction (finds and returns the first header)

2. Different regex patterns:

   • self.pattern (in process_escaped_tags) — specific to escaped tags, defined in __init__
   • r'^(#{1,6})\s+(.+)$' (in _extract_first_header) — for finding Markdown headers

3. Different signatures and context:

   • process_escaped_tags — instance method, uses self, includes logging
   • _extract_first_header — static utility method

The ~81% similarity is likely due to the shared high-level structure of "apply regex to string" — but this is the abstraction level of "a function that works with regexes," not duplication of business logic.

Merging these into one class would introduce unnecessary complexity and violate the Single Responsibility Principle. If any optimization is needed, it would be extracting regex compilation to module-level constants — not merging the functions.