How to fix warning: could not open directory, ignoring pattern in Git

# Check for syntax issues in .gitignore
cat .gitignore

# Look for:
# - Trailing backslashes at end of lines
# - Regex syntax like (pattern1|pattern2)
# - Incorrect wildcard usage

# Match specific file
debug.log

# Match all .log files in any directory
*.log

# Match logs directory recursively
**/logs/

# Match all .log files in logs and subdirectories  
logs/**/*.log

# Match at specific depth
a/**/b

# Test if a file is ignored and why
git check-ignore -v path/to/file.txt

# Test multiple files
git check-ignore -v file1.txt file2.log directory/

# Check all files in a directory
find . -type f | git check-ignore --stdin -v

# ❌ Invalid - never matches
path/to/dir\

# ✅ Correct
path/to/dir/

# ❌ Invalid - parentheses treated as literal characters
(debug|test)\.log

# ✅ Correct - use separate patterns
debug.log
test.log

# ❌ Only matches direct children
logs/*.log

# ✅ Matches recursively in all subdirectories
logs/**/*.log

# Matches both file and directory named 'temp'
temp

# Matches only directory named 'temp'  
temp/

# Remove all files from Git index (staging area)
git rm -r --cached .

# Re-add all files (respecting new .gitignore rules)
git add .

# Verify what will be committed
git status

# Commit the changes
git commit -m "Fix .gitignore - stop tracking previously ignored files"

# Check file encoding
file .gitignore

# Should show: .gitignore: ASCII text

# Convert line endings if needed (Linux/macOS)
dos2unix .gitignore

# Or use sed
sed -i 's/
$//' .gitignore

# Check for hidden characters
cat -A .gitignore