| <!DOCTYPE html> | |
| <meta charset="UTF-8"> | |
| <title>CSS Values and Units Test: computed value of 'background-position' when specified with calc() function</title> | |
| <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/"> | |
| <link rel="help" href="https://www.w3.org/TR/css-values-3/#calc-computed-value"> | |
| <meta name="flags" content=""> | |
| <meta content="This test verifies how 6 calc() functions are computed for 'background-position'." name="assert"> | |
| <script src="/resources/testharness.js"></script> | |
| <script src="/resources/testharnessreport.js"></script> | |
| <div id="target"></div> | |
| <script> | |
| function startTesting() | |
| { | |
| var targetElement = document.getElementById("target"); | |
| function verifyComputedStyle(property_name, initial_value, specified_value, expected_value, description) | |
| { | |
| test(function() | |
| { | |
| targetElement.style.setProperty(property_name, initial_value); | |
| /* | |
| The purpose of the initial_value is to act as a fallback | |
| value in case the calc() function in the specified value | |
| fails or in case it generates an invalid value. Since we | |
| are running 6 consecutive tests on the same element, | |
| then it is necessary to 'reset' its property to an | |
| initial value. | |
| */ | |
| targetElement.style.setProperty(property_name, specified_value); | |
| assert_equals(getComputedStyle(targetElement)[property_name], expected_value); | |
| }, description); | |
| } | |
| /* verifyComputedStyle(property_name, initial_value, specified_value, expected_value, description) */ | |
| verifyComputedStyle("background-position", "initial", "calc(2px + 3px) calc(4px + 5px)", "5px 9px", "testing background-position: calc(2px + 3px) calc(4px + 5px)"); | |
| verifyComputedStyle("background-position", "initial", "calc(18px - 7px) calc(19px - 7px)", "11px 12px", "testing background-position: calc(18px - 7px) calc(19px - 7px)"); | |
| verifyComputedStyle("background-position", "initial", "calc(4 * 5px) calc(6px * 4)", "20px 24px", "testing background-position: calc(4 * 5px) calc(6px * 4)"); | |
| verifyComputedStyle("background-position", "initial", "calc(100px / 4) calc(119px / 7)", "25px 17px", "testing background-position: calc(100px / 4) calc(119px / 7)"); | |
| verifyComputedStyle("background-position", "initial", "calc(6px + 21%) calc(7em + 22%)", "calc(21% + 6px) calc(22% + 112px)", "testing background-position: calc(6px + 21%) calc(7em + 22%)"); | |
| /* | |
| " | |
| (...) background-position has layout-dependent behavior for | |
| percentage values, and thus does not resolve percentages | |
| until used-value time. Due to this, background-position | |
| computation preserves the percentage in a calc(). (...) | |
| " | |
| https://www.w3.org/TR/css-values-3/#calc-computed-value | |
| */ | |
| verifyComputedStyle("background-position", "initial", "calc(-8px + 23%) calc(-9em + 24%)", "calc(23% - 8px) calc(24% - 144px)", "testing background-position: calc(-8px + 23%) calc(-9em + 24%)"); | |
| /* verifyComputedStyle(property_name, initial_value, specified_value, expected_value, description) */ | |
| } | |
| startTesting(); | |
| </script> |