| <!DOCTYPE html> |
| <script src="../../resources/testharness.js"></script> |
| <script src="../../resources/testharnessreport.js"></script> |
| |
| <style> |
| .spacer { |
| height: 1000px; |
| width: 1000px; |
| } |
| #scroller { |
| height: 100px; |
| width: 100px; |
| overflow: scroll; |
| } |
| |
| </style> |
| <div id=scroller> |
| <div class=spacer></div> |
| </div> |
| <div class=spacer></div> |
| |
| <script> |
| // FIXME: Make this smaller. crbug.com/414283. |
| var floatPrecision = 0.01; |
| |
| function testScroll(scrollOffset, expectedScrollOffset) { |
| // Scrolling DIV with scrollTop/scrollLeft |
| scroller.scrollTop = scrollOffset; |
| scroller.scrollLeft = scrollOffset; |
| assert_approx_equals(scroller.scrollTop, expectedScrollOffset, floatPrecision); |
| assert_approx_equals(scroller.scrollLeft, expectedScrollOffset, floatPrecision); |
| |
| //Scrolling the document with window.scroll |
| window.scroll(0,0); |
| scrollOffset++; |
| expectedScrollOffset++; |
| window.scroll(scrollOffset, scrollOffset); |
| assert_approx_equals(window.scrollY, expectedScrollOffset, floatPrecision); |
| assert_approx_equals(window.scrollX, expectedScrollOffset, floatPrecision); |
| |
| // Scrolling the document with window.scrollTo |
| window.scroll(0,0); |
| window.scrollTo(scrollOffset, scrollOffset); |
| assert_approx_equals(window.pageYOffset, expectedScrollOffset, floatPrecision); |
| assert_approx_equals(window.pageXOffset, expectedScrollOffset, floatPrecision); |
| |
| // Scrolling the document with window.scrollBy |
| window.scroll(1,1); |
| window.scrollBy(scrollOffset - 1, scrollOffset - 1); |
| assert_approx_equals(window.scrollY, expectedScrollOffset, floatPrecision); |
| assert_approx_equals(window.scrollX, expectedScrollOffset, floatPrecision); |
| } |
| |
| test( () => { |
| const setOffset = 4.2; |
| let expectedOffset = 4; |
| |
| // When fractional offsets are enabled, we should allow setting a fractional |
| // scroll offset. |
| if (internals.runtimeFlags.fractionalScrollOffsetsEnabled) |
| expectedOffset = 4.2; |
| |
| testScroll(setOffset, expectedOffset); |
| }, "Set fractional scroll offset without zoom"); |
| |
| test( () => { |
| testRunner.setPageZoomFactor(2); |
| |
| // Zooming provides additional granularity, regardless of the runtimeFlag |
| // being enabled or not. |
| const setOffset = 4.5; |
| const expectedOffset = 4.5; |
| testScroll(setOffset, expectedOffset); |
| }, "Set fractional scroll offset when zoomed"); |
| |
| test( () => { |
| testRunner.setPageZoomFactor(2); |
| |
| // Zooming provides additional granularity but we try to set a value beyond the 0.5 increment. |
| const setOffset = 4.6; |
| let expectedOffset = 4.5; |
| |
| // When fractional offsets are enabled, we should allow setting a fractional |
| // scroll offset. |
| if (internals.runtimeFlags.fractionalScrollOffsetsEnabled) |
| expectedOffset = 4.6; |
| |
| testScroll(setOffset, expectedOffset); |
| }, "Set fractional scroll offset to higher granularity when zoomed."); |
| |
| </script> |
