Attached is a patch to fix `ruby-toggle-string-quotes' in ruby-mode.el.
It was messing up when there were other quotes within the string.

I tried to send this via "M-x report-emacs-bug" and "C-c M-i", but that
404s with a Bad Request for Gmail.

=============================================
In GNU Emacs 25.0.90.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21
Version 10.9.5 (Build 13F1603))
 of 2016-01-30 built on builder10-9.local
Windowing system distributor 'Apple', version 10.3.1347
Configured using:
 'configure --with-ns '--enable-locallisppath=/Library/Application
 Support/Emacs/${version}/site-lisp:/Library/Application
 Support/Emacs/site-lisp''

Configured features:
NOTIFY ACL LIBXML2 ZLIB TOOLKIT_SCROLL_BARS NS

Important settings:
  locale-coding-system: utf-8-unix

Major mode: Magit

Minor modes in effect:
  yas-global-mode: t
  yas-minor-mode: t
  magit-auto-revert-mode: t
  global-git-commit-mode: t
  diff-auto-refine-mode: t
  helm-mode: t
  shell-dirtrack-mode: t
  async-bytecomp-package-mode: t
  autopair-global-mode: t
  global-hl-line-mode: t
  my-keys-mode: t
  recentf-mode: t
  global-linum-mode: t
  show-paren-mode: t
  winner-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
Open /Users/Sri/Desktop/emacs/test/lisp/progmodes/ruby-mode-tests.el
Turning on magit-auto-revert-mode...done
For information about GNU Emacs and the GNU system, type C-h C-a.
C-x g
Ran 1 tests, 0 results were as expected, 1 unexpected
Mark set
ruby-toggle-string-quotes
Ran 1 tests, 1 results were as expected
user-error: Beginning of history; no preceding item
delete-backward-char: Text is read-only [4 times]

Load-path shadows:
/Users/Sri/.emacs.d/elpa/helm-20160616.217/helm-multi-match hides
/Users/Sri/.emacs.d/elpa/helm-core-20160617.307/helm-multi-match

Features:
(shadow sort mail-extr emacsbug sendmail ruby-end ruby-mode-tests
ruby-mode smie ert ewoc debug helm-command helm-elisp helm-eval edebug
map yasnippet web-mode disp-table smart-mode-line-dark-theme
smart-mode-line rich-minority ob-ruby ob-python ob-calc calc-store
calc-trail calc-ext calc calc-loaddefs calc-macs org org-macro
org-footnote org-pcomplete org-list org-faces org-entities noutline
outline org-version ob-emacs-lisp ob ob-tangle ob-ref ob-lob ob-table
ob-exp org-src ob-keys ob-comint ob-core ob-eval org-compat org-macs
org-loaddefs find-func cal-menu calendar cal-loaddefs magit-blame
magit-stash magit-bisect magit-remote magit-commit magit-sequence magit
magit-apply magit-wip magit-log magit-diff smerge-mode magit-core
magit-autorevert autorevert filenotify magit-process magit-popup
magit-mode magit-git crm magit-section magit-utils git-commit log-edit
message rfc822 mml mml-sec epg mm-decode mm-bodies mm-encode mail-parse
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mailheader pcvs-util add-log with-editor tramp-sh helm-ls-git vc-git
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tramp-compat tramp-loaddefs trampver shell pcomplete format-spec
dired-aux helm-buffers helm-elscreen helm-tags helm-bookmark
helm-adaptive helm-info bookmark pp helm-locate helm-grep helm-regexp
helm-plugin helm-external helm-net browse-url xml helm-utils helm-help
helm-types helm easy-mmode helm-source eieio-compat helm-multi-match
helm-lib helm-config helm-easymenu edmacro kmacro async-bytecomp async
go-mode url url-proxy url-privacy url-expand url-methods url-history
url-cookie url-domsuf url-util mailcap find-file compile elisp-slime-nav
etags xref project coffee-mode rx bm autopair advice dired-x dired view
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wid-edit ediff-merg ediff-wind ediff-diff ediff-mult ediff-help
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server paren winner ring whitespace rect ffap thingatpt url-parse
auth-source eieio gnus-util mm-util help-fns mail-prsvr password-cache
url-vars eval-expr dash cl-seq finder-inf go-mode-autoloads eieio-core
cl-macs info package epg-config byte-opt bytecomp byte-compile cl-extra
help-mode easymenu cconv cl gv cl-loaddefs pcase cl-lib time-date
mule-util tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel ns-win ucs-normalize term/common-win tool-bar dnd
fontset image regexp-opt fringe tabulated-list newcomment elisp-mode
lisp-mode prog-mode register page menu-bar rfn-eshadow timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core frame
cl-generic cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian
slovak czech european ethiopic indian cyrillic chinese charscript
case-table epa-hook jka-cmpr-hook help simple abbrev minibuffer
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote kqueue cocoa ns
multi-tty make-network-process emacs)

Memory information:
((conses 16 540184 37755)
 (symbols 48 49498 0)
 (miscs 40 780 649)
 (strings 32 114429 10253)
 (string-bytes 1 3438490)
 (vectors 16 68800)
 (vector-slots 8 1051173 30787)
 (floats 8 805 427)
 (intervals 56 1055 494)
 (buffers 976 21))