MD047 - End Files with a Single Newline¶

Aliases: single-trailing-newline

What this rule does¶

Ensures every file ends with exactly one newline character, following standard text file conventions.

Why this matters¶

• Version control: Git and other tools expect files to end with newlines
• File concatenation: Prevents issues when combining files
• Terminal display: Files display correctly in command-line tools
• Cross-platform compatibility: Consistent behavior across operating systems

Examples¶

✅ Correct¶

# My Document

This is the content of my document.

The last line ends with a single newline.

(Note: There's an invisible newline after "newline.")

❌ Incorrect¶

# My Document

This is the content of my document.

The last line has no newline.

(Note: In the actual file, there would be no newline after "newline." - the file ends immediately)

# My Document  

This is the content of my document.

The last line has multiple newlines.

(Note: Multiple blank lines at the end)

🔧 Fixed¶

# My Document

This is the content of my document.

The last line now ends with a single newline.

(Note: Exactly one newline added at the end)

Configuration¶

This rule has no configuration options.

Automatic fixes¶

When enabled, this rule will:

• Add a newline if the file doesn't end with one
• Remove extra newlines if there are multiple
• Ensure exactly one newline at the end

Why this matters technically¶

• Many text editors automatically add this newline
• POSIX defines a line as ending with a newline
• Prevents "No newline at end of file" warnings
• Makes file processing more predictable

Special cases¶

• Empty files are considered valid
• Binary files are not checked
• The rule only checks for a single newline, not multiple blank lines (see MD012)

Learn more¶

• POSIX definition of a text file
• Why files should end with a newline

Related rules¶

• MD012 - Remove multiple consecutive blank lines
• MD022 - Add blank lines around headings
• MD031 - Add blank lines around code blocks