Codebase Inspection

Codebase Inspection with pygount

Analyze repositories for lines of code, language breakdown, file counts, and code-vs-comment ratios using pygount.

When to Use

• User asks for LOC (lines of code) count
• User wants a language breakdown of a repo
• User asks about codebase size or composition
• User wants code-vs-comment ratios
• General "how big is this repo" questions

Prerequisites

bashCopy code
python3 -m venv /path/to/approved-tools/pygount-venv
/path/to/approved-tools/pygount-venv/bin/python -m pip install pygount
/path/to/approved-tools/pygount-venv/bin/pygount --version

Choose a new, approved environment path; do not overwrite an existing environment or bypass externally managed Python protections. Use its pygount executable in the examples below, or activate that environment first.

1. Basic Summary (Most Common)

Get a full language breakdown with file counts, code lines, and comment lines:

bashCopy code
cd /path/to/repo
pygount --format=summary \
  --folders-to-skip=".git,node_modules,venv,.venv,__pycache__,.cache,dist,build,.next,.tox,.eggs,*.egg-info" \
  .

IMPORTANT: Always use --folders-to-skip to exclude dependency/build directories, otherwise pygount will crawl them and take a very long time or hang.

2. Common Folder Exclusions

Adjust based on the project type:

bashCopy code
# Python projects
--folders-to-skip=".git,venv,.venv,__pycache__,.cache,dist,build,.tox,.eggs,.mypy_cache"

# JavaScript/TypeScript projects
--folders-to-skip=".git,node_modules,dist,build,.next,.cache,.turbo,coverage"

# General catch-all
--folders-to-skip=".git,node_modules,venv,.venv,__pycache__,.cache,dist,build,.next,.tox,vendor,third_party"

3. Filter by Specific Language

bashCopy code
# Only count Python files
pygount --suffix=py --format=summary .

# Only count Python and YAML
pygount --suffix=py,yaml,yml --format=summary .

4. Detailed File-by-File Output

bashCopy code
# Default format shows per-file breakdown
pygount --folders-to-skip=".git,node_modules,venv" .

# Sort by code lines (pipe through sort)
pygount --folders-to-skip=".git,node_modules,venv" . | sort -t$'\t' -k1 -nr | head -20

5. Output Formats

bashCopy code
# Summary table (default recommendation)
pygount --format=summary .

# JSON output for programmatic use
pygount --format=json .

# Pipe-friendly: Language, file count, code, docs, empty, string
pygount --format=summary . 2>/dev/null

6. Interpreting Results

The summary table columns:

• Language — detected programming language
• Files — number of files of that language
• Code — lines of actual code (executable/declarative)
• Comment — lines that are comments or documentation
• % — percentage of total

Special pseudo-languages:

• __empty__ — empty files
• __binary__ — binary files (images, compiled, etc.)
• __generated__ — auto-generated files (detected heuristically)
• __duplicate__ — files with identical content
• __unknown__ — unrecognized file types

Pitfalls

1. Always exclude .git, node_modules, venv — without --folders-to-skip, pygount will crawl everything and may take minutes or hang on large dependency trees.
2. Markup classification varies — do not assume all Markdown is counted as comments. Inspect the installed version's output and lexer behavior.
3. Logical versus physical lines — pygount classification and wc -l measure different things. Label physical-line counts separately instead of treating them as a correction.
4. Large monorepos — for very large repos, consider using --suffix to target specific languages rather than scanning everything.

Measurement Contract

Before scanning, agree on the repository root and the population being measured. A language summary over application code is not comparable to a summary that also includes generated exports, vendored libraries, test fixtures, and caches. Record whether tests and documentation belong in the requested population. Explicit folder patterns replace pygount defaults; include [...] when you want to extend its defaults, then add project-specific exclusions.

Common Patterns: Comparable Snapshots

textCopy code
revision: full commit SHA, or explicitly identified dirty checkout
tool: pygount version
scope: absolute root and included subdirectories
exclusions: exact folder and filename patterns
duplicate policy: default deduplication or explicit --duplicates
outputs: summary plus JSON, stored outside the measured tree
errors: unknown, binary, generated, duplicate and error file counts

Compare snapshots only when these settings agree. If the tree is dirty, report that fact without stashing, discarding, or committing the user's changes. Use JSON for downstream parsing: human-readable summary column widths vary. Inspect a few representative files, including a generated file and a duplicate, before using totals to justify a migration or capacity decision.

Acceptance and Boundaries

• The command exits successfully and the output describes the intended root.
• Excluded dependencies are absent from the detailed file listing.
• Parse errors and unknown languages are reported, not silently folded into zero.
• Code-to-comment ratios state their denominator and treatment of empty lines.
• Two scans of an unchanged tree with identical settings yield identical counts.
• A file count or LOC change is not evidence of quality, risk, or productivity.
• Analysis is read-only; do not run repository code or upload private source.

Command semantics were checked against the primary pygount usage documentation. Recheck installed help before relying on new flags.