Test Assumptions
The tests make a number of assumptions of the user agent, and new tests can freely rely on these assumptions being true:
- The device is a full-color device.
- The device has viewport dimensions of at least 800px by 600px.
- The UA imposes no minimum font size.
- The
medium font-size computes to 16px. - The canvas background is
white. - The initial value of
color is black. - The user stylesheet is empty (except where indicated by the tests).
- The device is interactive and uses scroll bars.
- The HTML
div element is assigned display: block;, the unicode-bidi property may be declared, and no other property declarations. - The HTML
span element is assigned display: inline; and no other property declaration. - The HTML
p element is assigned display: block; - The HTML
li element is assigned display: list-item; - The HTML
table elements table, tbody, tr, and td are assigned the display values table, table-row-group, table-row, and table-cell, respectively. - The UA implements reasonable line-breaking behavior; e.g., it is assumed that spaces between alphanumeric characters provide line breaking opportunities and that UAs will not break at every opportunity, but only near the end of a line unless a line break is forced.
Tests for printing behavior make some further assumptions:
- The UA is set to print background colors and, if it supports graphics, background images.
- The UA implements reasonable page-breaking behavior; e.g., it is assumed that UAs will not break at every opportunity, but only near the end of a page unless a page break is forced.