sousa-gecko/devtools/client/shared/test/browser_inplace-editor_maxwidth.js

/* Any copyright is dedicated to the Public Domain.
   http://creativecommons.org/publicdomain/zero/1.0/ */
/* import-globals-from helper_inplace_editor.js */

"use strict";

loadHelperScript("helper_inplace_editor.js");

const MAX_WIDTH = 300;
const START_TEXT = "Start text";
const LONG_TEXT =
  "I am a long text and I will not fit in a 300px container. " +
  "I expect the inplace editor to wrap over more than two lines.";

// Test the inplace-editor behavior with a maxWidth configuration option
// defined.

add_task(async function () {
  await addTab("data:text/html;charset=utf-8,inplace editor max width tests");
  const { host, doc } = await createHost();

  info("Testing the maxWidth option in pixels, to precisely check the size");
  await new Promise(resolve => {
    createInplaceEditorAndClick(
      {
        multiline: true,
        maxWidth: MAX_WIDTH,
        start: testMaxWidth,
        done: resolve,
      },
      doc,
      START_TEXT
    );
  });

  host.destroy();
  gBrowser.removeCurrentTab();
});

const testMaxWidth = async function (editor) {
  is(editor.input.value, START_TEXT, "Span text content should be used");
  Assert.less(
    editor.input.offsetWidth,
    MAX_WIDTH,
    "Input width should be strictly smaller than MAX_WIDTH"
  );
  is(getLines(editor.input), 1, "Input should display 1 line of text");

  info("Check a text is on several lines if it does not fit MAX_WIDTH");
  for (const key of LONG_TEXT) {
    EventUtils.sendChar(key);
    checkScrollbars(editor.input);
  }

  is(editor.input.value, LONG_TEXT, "Long text should be the input value");
  is(
    editor.input.offsetWidth,
    MAX_WIDTH,
    "Input width should be the same as MAX_WIDTH"
  );
  is(getLines(editor.input), 3, "Input should display 3 lines of text");
  checkScrollbars(editor.input);

  info("Delete all characters on line 3.");
  while (getLines(editor.input) === 3 && editor.input.value) {
    EventUtils.sendKey("BACK_SPACE");
    // wait for a tick so the input can be re-rendered
    await waitForTick();
    checkScrollbars(editor.input);
  }

  is(
    editor.input.offsetWidth,
    MAX_WIDTH,
    "Input width should be the same as MAX_WIDTH"
  );
  is(getLines(editor.input), 2, "Input should display 2 lines of text");
  checkScrollbars(editor.input);

  info("Delete all characters on line 2.");
  while (getLines(editor.input) === 2 && editor.input.value) {
    EventUtils.sendKey("BACK_SPACE");
    // wait for a tick so the input can be re-rendered
    await waitForTick();
    checkScrollbars(editor.input);
  }

  is(getLines(editor.input), 1, "Input should display 1 line of text");
  checkScrollbars(editor.input);

  info("Delete all characters.");
  while (editor.input.value) {
    EventUtils.sendKey("BACK_SPACE");
    // wait for a tick so the input can be re-rendered
    await waitForTick();
    checkScrollbars(editor.input);
  }

  Assert.less(
    editor.input.offsetWidth,
    MAX_WIDTH,
    "Input width should again be strictly smaller than MAX_WIDTH"
  );
  Assert.greater(
    editor.input.offsetWidth,
    0,
    "Even with no content, the input has a non-zero width"
  );
  is(getLines(editor.input), 1, "Input should display 1 line of text");
  checkScrollbars(editor.input);

  info("Leave the inplace-editor");
  EventUtils.sendKey("RETURN");
};

/**
 * Retrieve the current number of lines displayed in the provided textarea.
 *
 * @param {DOMNode} textarea
 * @return {number} the number of lines
 */
function getLines(textarea) {
  const win = textarea.ownerDocument.defaultView;
  const style = win.getComputedStyle(textarea);
  return Math.floor(textarea.clientHeight / parseFloat(style.fontSize));
}

/**
 * Verify that the provided textarea has no vertical or horizontal scrollbar.
 *
 * @param {DOMNode} textarea
 */
function checkScrollbars(textarea) {
  is(
    textarea.scrollHeight,
    textarea.clientHeight,
    "Textarea should never have vertical scrollbars"
  );
  is(
    textarea.scrollWidth,
    textarea.clientWidth,
    "Textarea should never have horizontal scrollbars"
  );
}