Rule - MD056

Property	Value
Aliases	md056, table-column-count
Autofix Available	No
Enabled By Default	Yes

Summary

Table column count.

Reasoning

Correctness

A GFM table is defined by its header row, and every other row in the table is expected to have the same number of cells as that header row. When a row has fewer cells than the header row, the renderer pads the row with empty cells, so data the author intended to provide is missing. When a row has more cells than the header row, the extra cells are silently dropped, so data the author provided is lost. In both cases the mismatch is almost always an accidental missing or extra pipe (|) character, making it worth flagging.

Examples

Failure Scenarios

This rule triggers when a table row does not have the same number of cells as the table's header row. This can be because the row has too few cells:

| Heading | Heading |
| ------- | ------- |
| Cell |

or because the row has too many cells:

| Heading | Heading |
| ------- | ------- |
| Cell | Cell | Cell |

Correct Scenarios

This rule does not trigger when every row in the table has the same number of cells as the header row:

| Heading | Heading |
| ------- | ------- |
| Cell | Cell |

Note that a table's header row and its delimiter row must already have the same number of cells, or the block is not recognized as a table at all. In that case there is no table for this rule to examine.

Configuration

Prefixes
plugins.md056.
plugins.table-column-count.

Value Name	Type	Default	Description
enabled	boolean	True	Whether the Rule Plugin is enabled.

As tables are only recognized when the Markdown Tables extension is enabled, this rule has no effect unless that extension is turned on.

Origination of Rule

This rule is largely inspired by the MarkdownLint rule MD056.