Add Sourcegraph Button to GitHub

Add a 'Sourcrgraph' Button on GitHub repository & file page.

As of 13. 02. 2020. See the latest version.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name    Add Sourcegraph Button to GitHub
// @description Add a 'Sourcrgraph' Button on GitHub repository & file page.
// @version 3
// @grant   none
// @inject-into auto
// @supportURL https://github.com/whtsky/userscripts/issues
// @match   https://github.com/*
// @namespace https://greasyfork.org/users/164794
// ==/UserScript==

function goToSourcegraph(event) {
  event.preventDefault()
  var pats = [
    [
      '^/([^/]+)/([^/]+)/tree/([^/]+)$',
      '/github.com/$1/$2@$3',
      '^/github.com/([^/]+)/([^/@]+)@([^/]+)$',
      '/$1/$2/tree/$3',
    ],
    [
      '^/([^/]+)/([^/]+)/tree/([^/]+)/(.+)$',
      '/github.com/$1/$2@$3/-/tree/$4',
      '^/github.com/([^/]+)/([^/@]+)@([^/]+)/-/tree/(.+)$',
      '/$1/$2/tree/$3/$4',
    ],
    ['^/([^/]+)/([^/]+)/blob/([^/]+)/(.+)$', '/github.com/$1/$2@$3/-/blob/$4', '', ''],
    ['^/([^/]+)/([^/]+)$', '/github.com/$1/$2', '^/github.com/([^/]+)/([^/]+)$', '/$1/$2'],
    ['^/([^/]+)$', '/$1', '^/([^/]+)$', '/$1'],
  ]
  var pathname = window.location.pathname
  for (var i = 0; i < pats.length; i++) {
    var pat = pats[i]
    var r, pathname2
    if (window.location.hostname === 'github.com') {
      if (pat[0] === '') {
        continue
      }
      r = new RegExp(pat[0])
      if (pathname.match(r)) {
        pathname2 = pathname.replace(r, pat[1])
        window.location = 'https://sourcegraph.com' + pathname2
        return
      }
    } else {
      if (pat[2] === '') {
        continue
      }
      r = new RegExp(pat[2])
      if (pathname.match(r)) {
        pathname2 = pathname.replace(r, pat[3])
        window.location = 'https://github.com' + pathname2
        return
      }
    }
  }
  alert('Unable to jump to Sourcegraph (no matching URL pattern).')
}

function createButton() {
  if (document.querySelector('#userscript__sourcegraph')) {
    return
  }
  const targetBtn =
    document.querySelector('#raw-url') || document.querySelector(':not(.commit-links-group) > a.BtnGroup-item')
  if (targetBtn) {
    const newBtn = targetBtn.cloneNode(false)
    newBtn.setAttribute('id', 'userscript__sourcegraph')
    newBtn.setAttribute('class', 'btn btn-sm BtnGroup-item')
    newBtn.textContent = 'Sourcegraph'
    newBtn.href = ''
    newBtn.addEventListener('click', goToSourcegraph)
    targetBtn.parentNode.insertBefore(newBtn, targetBtn)
  }
}

const observer = new MutationObserver(function() {
  observer.disconnect()
  createButton()
  observer.observe(document.body, { childList: true, subtree: true })
})
observer.observe(document.body, { childList: true, subtree: true })

createButton()