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Test Info: Warnings
- This test gets skipped with pattern: http3 OR http2
- Manifest: devtools/server/tests/browser/browser.toml
/* Any copyright is dedicated to the Public Domain.
"use strict";
// Test that getFontPreviewData of the style utils generates font previews.
const TEST_URI = "data:text/html,<title>Test getFontPreviewData</title>";
add_task(async function () {
await addTab(TEST_URI);
await SpecialPowers.spawn(gBrowser.selectedBrowser, [], async function () {
const { require } = ChromeUtils.importESModule(
);
const {
getFontPreviewData,
const font = Services.appinfo.OS === "WINNT" ? "Arial" : "Liberation Sans";
let fontPreviewData = getFontPreviewData(font, content.document);
ok(
fontPreviewData?.dataURL,
"Returned a font preview with a valid dataURL"
);
// Create <img> element and load the generated preview into it
// to check whether the image is valid and get its dimensions
const image = content.document.createElement("img");
let imageLoaded = new Promise(loaded =>
image.addEventListener("load", loaded, { once: true })
);
image.src = fontPreviewData.dataURL;
await imageLoaded;
const { naturalWidth: widthImage1, naturalHeight: heightImage1 } = image;
Assert.greater(widthImage1, 0, "Preview width is greater than 0");
Assert.greater(heightImage1, 0, "Preview height is greater than 0");
// Create a preview with different text and compare
// its dimensions with the first one
fontPreviewData = getFontPreviewData(font, content.document, {
previewText: "Abcdef",
});
ok(
fontPreviewData?.dataURL,
"Returned a font preview with a valid dataURL"
);
imageLoaded = new Promise(loaded =>
image.addEventListener("load", loaded, { once: true })
);
image.src = fontPreviewData.dataURL;
await imageLoaded;
const { naturalWidth: widthImage2, naturalHeight: heightImage2 } = image;
// Check whether the width is greater than with the default parameters
// and that the height is the same
Assert.greater(
widthImage2,
widthImage1,
"Preview width is greater than with default parameters"
);
Assert.strictEqual(
heightImage2,
heightImage1,
"Preview height is the same as with default parameters"
);
// Create a preview with smaller font size and compare
// its dimensions with the first one
fontPreviewData = getFontPreviewData(font, content.document, {
previewFontSize: 20,
});
ok(
fontPreviewData?.dataURL,
"Returned a font preview with a valid dataURL"
);
imageLoaded = new Promise(loaded =>
image.addEventListener("load", loaded, { once: true })
);
image.src = fontPreviewData.dataURL;
await imageLoaded;
const { naturalWidth: widthImage3, naturalHeight: heightImage3 } = image;
// Check whether the width and height are smaller than with the default parameters
Assert.less(
widthImage3,
widthImage1,
"Preview width is smaller than with default parameters"
);
Assert.less(
heightImage3,
heightImage1,
"Preview height is smaller than with default parameters"
);
// Create a preview with multiple lines and compare
// its dimensions with the first one
fontPreviewData = getFontPreviewData(font, content.document, {
previewText: "Abc\ndef",
});
ok(
fontPreviewData?.dataURL,
"Returned a font preview with a valid dataURL"
);
imageLoaded = new Promise(loaded =>
image.addEventListener("load", loaded, { once: true })
);
image.src = fontPreviewData.dataURL;
await imageLoaded;
const { naturalWidth: widthImage4, naturalHeight: heightImage4 } = image;
// Check whether the width is the same as with the default parameters
// and that the height is greater
Assert.strictEqual(
widthImage4,
widthImage1,
"Preview width is the same as with default parameters"
);
Assert.greater(
heightImage4,
heightImage1,
"Preview height is greater than with default parameters"
);
});
});