Continuation lines indentation.

Continuation lines should align wrapped elements either vertically
using Python's implicit line joining inside parentheses, brackets
and braces, or using a hanging indent.

When using a hanging indent these considerations should be applied:
- there should be no arguments on the first line, and
- further indentation should be used to clearly distinguish itself
  as a continuation line.

Okay: a = (\n)
E123: a = (\n    )

Okay: a = (\n    42)
E121: a = (\n   42)
E122: a = (\n42)
E123: a = (\n    42\n    )
E124: a = (24,\n     42\n)
E125: if (\n    b):\n    pass
E126: a = (\n        42)
E127: a = (24,\n      42)
E128: a = (24,\n    42)
E129: if (a or\n    b):\n    pass
E131: a = (\n    42\n 24)

Don't use spaces around the '=' sign in function arguments.

Don't use spaces around the '=' sign when used to indicate a
keyword argument or a default parameter value, except when
using a type annotation.

Okay: def complex(real, imag=0.0):
Okay: return magic(r=real, i=imag)
Okay: boolean(a == b)
Okay: boolean(a != b)
Okay: boolean(a <= b)
Okay: boolean(a >= b)
Okay: def foo(arg: int = 42):
Okay: async def foo(arg: int = 42):

E251: def complex(real, imag = 0.0):
E251: return magic(r = real, i = imag)
E252: def complex(real, image: float=0.0):

MD003 - Header style

Tags: headers

Aliases: header-style

Parameters: style ("consistent", "atx", "atxclosed", "setext", "setextwith_atx"; default "consistent")

This rule is triggered when different header styles (atx, setext, and 'closed' atx) are used in the same document:

# ATX style H1

## Closed ATX style H2 ##

Setext style H1
===============

Be consistent with the style of header used in a document:

# ATX style H1

## ATX style H2

The setextwithatx doc style allows atx-style headers of level 3 or more in documents with setext style headers:

Setext style H1
===============

Setext style H2
---------------

### ATX style H3

Note: the configured header style can be a specific style to use (atx, atxclosed, setext, setextwith_atx), or simply require that the usage be consistent within the document.

MD006 - Consider starting bulleted lists at the beginning of the line

Tags: bullet, ul, indentation

Aliases: ul-start-left

This rule is triggered when top level lists don't start at the beginning of a line:

Some text

  * List item
  * List item

To fix, ensure that top level list items are not indented:

Some test

* List item
* List item

Rationale: Starting lists at the beginning of the line means that nested list items can all be indented by the same amount when an editor's indent function or the tab key is used to indent. Starting a list 1 space in means that the indent of the first nested list is less than the indent of the second level (3 characters if you use 4 space tabs, or 1 character if you use 2 space tabs).

MD006 - Consider starting bulleted lists at the beginning of the line

Tags: bullet, ul, indentation

Aliases: ul-start-left

This rule is triggered when top level lists don't start at the beginning of a line:

Some text

  * List item
  * List item

To fix, ensure that top level list items are not indented:

Some test

* List item
* List item

Rationale: Starting lists at the beginning of the line means that nested list items can all be indented by the same amount when an editor's indent function or the tab key is used to indent. Starting a list 1 space in means that the indent of the first nested list is less than the indent of the second level (3 characters if you use 4 space tabs, or 1 character if you use 2 space tabs).

MD012 - Multiple consecutive blank lines

Tags: whitespace, blank_lines

Aliases: no-multiple-blanks

This rule is triggered when there are multiple consecutive blank lines in the document:

Some text here


Some more text here

To fix this, delete the offending lines:

Some text here

Some more text here

Note: this rule will not be triggered if there are multiple consecutive blank lines inside code blocks.

MD031 - Fenced code blocks should be surrounded by blank lines

Tags: code, blank_lines

Aliases: blanks-around-fences

This rule is triggered when fenced code blocks are either not preceded or not followed by a blank line:

Some text
```
Code block
```

```
Another code block
```
Some more text

To fix this, ensure that all fenced code blocks have a blank line both before and after (except where the block is at the beginning or end of the document):

Some text

```
Code block
```

```
Another code block
```

Some more text

Rationale: Aside from aesthetic reasons, some parsers, including kramdown, will not parse fenced code blocks that don't have blank lines before and after them.

MD031 - Fenced code blocks should be surrounded by blank lines

Tags: code, blank_lines

Aliases: blanks-around-fences

This rule is triggered when fenced code blocks are either not preceded or not followed by a blank line:

Some text
```
Code block
```

```
Another code block
```
Some more text

To fix this, ensure that all fenced code blocks have a blank line both before and after (except where the block is at the beginning or end of the document):

Some text

```
Code block
```

```
Another code block
```

Some more text

Rationale: Aside from aesthetic reasons, some parsers, including kramdown, will not parse fenced code blocks that don't have blank lines before and after them.