[deadstrobe5]

Description

TableProcessor.test splits and strips every line of the block, but only the first two rows are needed outside the single-column-with-border case. Blocks that other processors take apart one line at a time, such as headers with no blank lines between them, return the rest of the block to be tested again, so the table test alone made those blocks quadratic. tables is enabled by default in MkDocs.

This splits off only the first two rows. The single-column case, which checks that every row has a pipe, still reads all the rows.

Median of 5 alternating runs in one process, CPython 3.14, extensions toc, tables and fenced_code:

Document	Before	After
4,000 lines of # H	725 ms	172 ms
500 tight headers with text	71.9 ms	48.2 ms
300 KB of the repo docs	180 ms	177 ms
2 KB page	1.68 ms	1.65 ms

The old and new code give the same HTML on 30,000 generated documents mixing tables, single-column tables, headers, lists and other blocks.

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[waylan]

I think maybe we should add a couple additional tests to ensure we are not breaking the existing behavior.

# Table
| A | B |
|---|---|
| a | b |

Not a table
| A | B |
|---|---|
| a | b |

We want to ensure that the first one is properly recognized as a table and the second is not. Based on the code, I expect the second to pass, but I am concerned that the first may not.