Commit 013bdbce authored by Emilio Cobos Álvarez's avatar Emilio Cobos Álvarez Committed by Pier Angelo Vendrame
Browse files

Bug 1918454 - Prevent divide by zero when inverting effective zoom.... 

Bug 1918454 - Prevent divide by zero when inverting effective zoom. r=firefox-style-system-reviewers,layout-reviewers,boris

See comment.

Differential Revision: https://phabricator.services.mozilla.com/D222090
parent b698da4d

servo/components/style/properties/properties.mako.rs

+4 −1
Original line number Diff line number Diff line
@@ -2715,7 +2715,10 @@ impl<'a> StyleBuilder<'a> { 
    pub fn resolved_specified_zoom(&self) -> computed::Zoom {

        let zoom = self.specified_zoom();

        if zoom.is_document() {

            self.inherited_effective_zoom().inverted()

            // If our inherited effective zoom has derived to zero, there's not much we can do.

            // This value is not exposed to content anyways (it's used for scrollbars and to avoid

            // zoom affecting canvas).

            self.inherited_effective_zoom().inverted().unwrap_or(computed::Zoom::ONE)

        } else {

            zoom

        }

servo/components/style/values/computed/box.rs

+5 −2
Original line number Diff line number Diff line
@@ -365,8 +365,11 @@ impl Zoom { 


    /// Returns the inverse of our value.

    #[inline]

    pub fn inverted(&self) -> Self {

        Self(Self::ONE.0 / self.0)

    pub fn inverted(&self) -> Option<Self> {

        if self.0.value == 0 {

            return None;

        }

        Some(Self(Self::ONE.0 / self.0))

    }



    /// Returns the value as a float.

testing/web-platform/tests/css/css-viewport/zoom/textarea-very-small-zoom-crash.html

0 → 100644
+6 −0
Original line number Diff line number Diff line 
<style>

*:nth-of-type(1) {

  zoom: 5%;

}

</style>

<textarea>