Atom File Name Tab Disambiguator

init.js

// This makes file names in the tabs a little bit easier to read, especially
// when you have TONS of identically prefixed and very long named files.

// It'll convert a row of tabs that looks like this (USELESS):
//   [NewsFeedConfigurati…][NewsFeedConfigurati…][NewsFeedConfigurati…]

// And make it look a little more like this (BETTER):
//   [NewsFee…ManagerSpec.js][NewsFee…eView.react.js][NewsFee…ainer.react.js]

// And optionally, if TRIM_EXTENSION is set to true, like this (BEST):
//   [NewsFee…inManagerSpec‗][NewsFee…etailPageView‗][NewsFee…ViewContainer‗]

// Just create 'init.js' in your ~/.atom directory.
// You'll need to restart Atom to load it, sorry.

const TRIM_MAX_LEN = 22;
const TRIM_TRAILING = 14;
const TRIM_ELLIPSES = "…";
const TRIM_EXTENSION = true;      // Trims the extension first if too long.
const TRIM_EXTENSION_CHAR = "‗";  // Make a blank string to leave out.

atom.workspace.observeTextEditors(editor => {
  const currentTitle = editor.getTitle();
  if (currentTitle !== "untitled" && currentTitle.length > TRIM_MAX_LEN) {
    const dotIndex = currentTitle.indexOf(".");
    const workTitle = (TRIM_EXTENSION && dotIndex !== -1) ?
      currentTitle.slice(0, dotIndex) + TRIM_EXTENSION_CHAR : currentTitle;

    const trimmedTitle = (workTitle.length > TRIM_MAX_LEN) ?
      (
        workTitle.slice(0, TRIM_MAX_LEN - TRIM_TRAILING - TRIM_ELLIPSES.length) +
        TRIM_ELLIPSES +
        workTitle.slice(TRIM_TRAILING * -1)
      ) : workTitle;

    editor.getTitle = () => trimmedTitle;
    editor.emitter.emit("did-change-title", editor.getTitle());
  }
});

atom.workspace.onDidOpen(event => {
  for (item of event.pane.items) {
    if (item.emitter) {
      item.emitter.emit("did-change-title", item.getTitle());
    }
  }
});

Inspired initially by https://gist.github.com/tribou/53b508b65b390183e4b23678e5b0816f