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"use strict";
function assert_whether_monospace(textElement, epsilon, expectsMonoSpace) {
// To verify that the text element is monospace, we compare its width against
// the its length times the width of a period character.
const text = textElement.textContent;
textElement.textContent = ".";
const charWidth = textElement.getBoundingClientRect().width;
textElement.textContent = text;
const textWidth = textElement.getBoundingClientRect().width;
if (expectsMonoSpace) {
assert_approx_equals(textWidth, text.length * charWidth, epsilon);
} else {
assert_greater_than(Math.abs(textWidth - text.length * charWidth), epsilon);
}
}
function assert_is_monospace(textElement, epsilon) {
assert_whether_monospace(textElement, epsilon, true);
}
function assert_is_not_monospace(textElement, epsilon) {
assert_whether_monospace(textElement, epsilon, false);
}