Csharp Code Cleanup

C# Code Cleanup Skill

⚠️ C# ONLY - This skill is specifically for C# code formatting and StyleCop violations in .NET projects. It does NOT support other languages (Java, TypeScript, Python, etc.).

Automated code cleanup using ReSharper CLI (jb cleanupcode) to fix StyleCop violations, enforce code style standards, and maintain consistent formatting in C# projects.

When to Use This Skill

Manual Invocation

• User explicitly requests code cleanup: /csharp-cleanup, /resharper-cleanup, /stylecop-fix
• User asks to "fix StyleCop violations" or "format code"
• User wants to run cleanup before committing changes

Assisted Detection (Automatic Suggestion)

• You detect SA#### violations in build output → suggest cleanup
• User's build fails with StyleCop errors → offer to fix automatically
• After modifying C# files → suggest cleanup before commit (optional)

IMPORTANT: Always require user confirmation before running cleanup. Never run automatically without permission.

Core Workflow

1. Tool Installation Check

Before running cleanup, verify ReSharper CLI is installed:

jb cleanupcode --version

If not installed:

# Offer to install globally
dotnet tool install -g JetBrains.ReSharper.GlobalTools

Verification after install:

jb cleanupcode --version
# Should output version info (e.g., "JetBrains CleanupCode 2024.3.0")

2. Determine Cleanup Scope

Default scope: Modified files only

# Get list of modified .cs files
git diff --name-only --diff-filter=ACMR "*.cs"
git diff --cached --name-only --diff-filter=ACMR "*.cs"

Alternative scopes:

• Specific files: User-provided paths
• Entire solution: All .cs files in solution
• Pattern-based: Files matching glob pattern (e.g., src/**/*.cs)

3. Safety Checks

Before executing cleanup, verify:

# 1. Find solution file (.sln or .slnx)
# Supports both traditional .sln and XML-based .slnx formats
SOLUTION_FILE=$(find . -maxdepth 1 \( -name "*.sln" -o -name "*.slnx" \) | head -1)
if [[ -z "$SOLUTION_FILE" ]]; then
  echo "ERROR: No solution file (.sln or .slnx) found in current directory"
  exit 1
fi
echo "Found solution: $SOLUTION_FILE"

# 2. Check for .DotSettings file (optional but recommended)
SOLUTION_SETTINGS="${SOLUTION_FILE}.DotSettings"
if [[ -f "$SOLUTION_SETTINGS" ]]; then
  echo "Using solution settings: $SOLUTION_SETTINGS"
fi

Note: ReSharper CLI supports both .sln (traditional) and .slnx (XML-based Visual Studio solution format) files.

4. Run ReSharper Cleanup

For specific files:

jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings \
  --include="src/file1.cs;src/file2.cs;tests/file3.cs" \
  --verbosity=WARN

For entire solution:

jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings \
  --verbosity=WARN

Command parameters:

• --profile: Cleanup profile to use (default: "Built-in: Full Cleanup")
• --settings: Path to .DotSettings file with cleanup configuration
• --include: Semicolon-separated list of files to clean (optional)
• --verbosity: Output verbosity (VERBOSE, INFO, WARN, ERROR)

5. Parse Output and Report Results

ReSharper CLI output format:

JetBrains CleanupCode 2024.3.0
Running in 64-bit mode, .NET Core 6.0.36 under Microsoft Windows 10.0.26200
Processing solution file MySolution.sln
  Inspecting project MyApp.Api
  Inspecting project MyApp.Tests
Cleanup completed in 15.2s

Report to user:

✓ Code cleanup completed successfully
  - Cleaned up 5 files in 15.2s
  - Modified: src/Services/UserService.cs
  - Modified: src/Persistence/Repository.cs
  - Modified: tests/UserServiceTests.cs

Run 'dotnet build' to verify the cleanup fixed violations.

6. Verify Cleanup Success

Suggest rebuilding to verify violations are fixed:

dotnet build --no-restore

If violations persist, report them and suggest configuration alignment.

StyleCop Violation Detection

When you see build output, scan for StyleCop violations:

Pattern to detect: error SA####: or warning SA####:

Example build output:

src/Services/UserService.cs(10,1): error SA1200: Using directive should appear within a namespace declaration [MyApp.Api.csproj]
src/Persistence/Repository.cs(25,9): error SA1309: Field '_repository' should not begin with an underscore [MyApp.Api.csproj]

Detection logic:

1. Parse lines containing SA####
2. Extract violation code (e.g., SA1200, SA1309)
3. Extract file path and line number
4. Group violations by file

Offer cleanup:

I detected StyleCop violations in the build output:
  - SA1200: Using directive placement (2 files)
  - SA1309: Field naming (1 file)

Would you like me to run ReSharper cleanup to fix these? (/csharp-cleanup)

Command Variants

/csharp-cleanup (default)

Runs cleanup on modified files only:

# Get modified files
MODIFIED_FILES=$(git diff --name-only --diff-filter=ACMR "*.cs" && git diff --cached --name-only --diff-filter=ACMR "*.cs")

# Run cleanup
jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings \
  --include="$MODIFIED_FILES"

/csharp-cleanup --all

Runs cleanup on entire solution:

jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings

/csharp-cleanup --verify

Dry-run mode (shows what would change without applying):

# ReSharper CLI doesn't have built-in dry-run
# Instead: create git stash, run cleanup, show diff, restore stash
git stash push -m "pre-cleanup-verify"
jb cleanupcode MySolution.sln --include="$FILES"
git diff --stat
echo "Run '/csharp-cleanup' to apply these changes"
git reset --hard HEAD
git stash pop

/csharp-cleanup file1.cs file2.cs

Runs cleanup on specific files:

jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings \
  --include="file1.cs;file2.cs"

/csharp-cleanup src/**/*.cs

Runs cleanup on files matching pattern:

# Expand glob pattern to file list
FILES=$(find src -name "*.cs" -type f | tr '\n' ';')
jb cleanupcode MySolution.sln \
  --profile="Built-in: Full Cleanup" \
  --settings=MySolution.sln.DotSettings \
  --include="$FILES"

/csharp-cleanup --profile="StyleCop Full Cleanup"

Uses specific cleanup profile:

jb cleanupcode MySolution.sln \
  --profile="StyleCop Full Cleanup" \
  --settings=MySolution.sln.DotSettings

/csharp-cleanup --list-profiles

Lists available cleanup profiles:

# ReSharper CLI doesn't have --list-profiles command
# Read from .DotSettings file or show built-in profiles
echo "Available cleanup profiles:"
echo "  - Built-in: Full Cleanup (default)"
echo "  - Built-in: Reformat Code"
echo "  - Built-in: Reformat & Apply Code Style"
echo ""
echo "Custom profiles (from .DotSettings):"
grep -A1 'CleanupProfile' MySolution.sln.DotSettings || echo "  (none found)"

Safety Features

Uncommitted Changes Warning

# Check if there are uncommitted changes
if [[ -n $(git status --porcelain) ]]; then
  echo "Warning: You have uncommitted changes. Cleanup will modify files."
  echo "Consider committing or stashing changes first."
  # Require explicit confirmation
fi

File Preview

Before running cleanup on many files, show preview:

FILE_COUNT=$(echo "$MODIFIED_FILES" | wc -l)
if [[ $FILE_COUNT -gt 10 ]]; then
  echo "Will clean up $FILE_COUNT files:"
  echo "$MODIFIED_FILES" | head -10
  echo "...and $(($FILE_COUNT - 10)) more"
  echo ""
  echo "Proceed with cleanup? (y/n)"
fi

Error Handling

ReSharper CLI Not Installed

ReSharper CLI (jb cleanupcode) is not installed.

Install globally with:
  dotnet tool install -g JetBrains.ReSharper.GlobalTools

Or install locally:
  dotnet tool install JetBrains.ReSharper.GlobalTools

Would you like me to install it globally? (y/n)

Solution File Not Found

ERROR: No solution file (.sln or .slnx) found in current directory.

Please navigate to the solution directory or ensure a solution file exists.
Supported formats:
  - .sln (Visual Studio solution)
  - .slnx (XML-based Visual Studio solution)

Cleanup Failed

ERROR: ReSharper cleanup failed with exit code 1

Common causes:
  - Solution cannot be restored (missing NuGet packages)
  - Compilation errors in the solution
  - Invalid .DotSettings configuration

Try running 'dotnet build' first to identify issues.

Violations Persist After Cleanup

Warning: StyleCop violations still present after cleanup:
  - SA1200: Using directive placement (2 files)

This may indicate:
  1. .DotSettings and .editorconfig have conflicting rules
  2. Some rules require manual fixes (e.g., SA1600 documentation)
  3. Cleanup profile doesn't include these rules

Would you like me to check configuration alignment?

Fallback: dotnet format

If ReSharper CLI is not available and user declines installation:

# Use dotnet format as fallback
dotnet format MySolution.sln --verify-no-changes --verbosity diagnostic

# If changes needed:
dotnet format MySolution.sln

Warning message:

Note: Using 'dotnet format' instead of ReSharper CLI.
  - Only .editorconfig rules will be applied
  - .DotSettings cleanup profiles will be ignored
  - Some StyleCop rules may not be fixed

For full cleanup support, install ReSharper CLI.

Integration with Other Skills

Git Atomic Workflow Integration

When user is about to commit, suggest cleanup:

You have modified 3 C# files with unstaged changes.
Would you like to run code cleanup before committing? (/csharp-cleanup)

Build Integration

After detecting build failures with SA#### violations:

Build failed with 5 StyleCop violations.
Run /csharp-cleanup to automatically fix these violations.

Configuration Files Reference

.DotSettings Files (ReSharper Configuration)

• <SolutionName>.sln.DotSettings - Solution-level settings
• CompanyWide.DotSettings - Company-wide standards (optional)
• Project-specific .DotSettings files

Used by: ReSharper CLI (jb cleanupcode) Contains: Cleanup profiles, code style settings, formatting rules

.editorconfig (EditorConfig Standard)

• .editorconfig - Typically in solution root

Used by: IDEs, dotnet format, analyzers Contains: Formatting rules, analyzer severity, code style preferences

stylecop.json (StyleCop Analyzer Configuration)

• stylecop.json - Typically in solution root

Used by: StyleCop.Analyzers NuGet package Contains: StyleCop-specific settings (documentation rules, naming rules)

Limitations

What ReSharper Cleanup Cannot Fix

• SA1600-SA1649: Documentation rules (require manual documentation)
• SA1300-SA1316: Naming rules that require renaming (may break API compatibility)
• SA0001: XML comment analysis (disabled in many projects)
• Complex refactoring that requires understanding business logic

Cleanup Can Introduce Changes That:

• Affect git history (formatting changes in unrelated lines)
• Trigger PR review for style changes
• May conflict with other branches

Recommendation: Run cleanup on isolated changes, not on large feature branches with many modifications.

Performance

• Full solution cleanup can take 30-60 seconds on large codebases
• Modified file cleanup is faster (5-10 seconds for 5-10 files)
• ReSharper CLI requires solution restore (downloads NuGet packages if needed)

Checklist Before Running Cleanup

• ReSharper CLI is installed (jb cleanupcode --version)
• Solution file (.sln or .slnx) exists and is valid
• .DotSettings configuration file exists (optional but recommended)
• User has confirmed they want to run cleanup
• Scope is clear (modified files, all files, specific files)
• User is aware cleanup will modify files

Success Indicators

• ✅ Cleanup completes without errors
• ✅ Build succeeds after cleanup (dotnet build)
• ✅ StyleCop violations are resolved
• ✅ Git diff shows only formatting/style changes
• ✅ Code still compiles and tests pass