Enable tests in emacs-snapshot

Undercover is currently disabled for emacs-snapshot because it needs
to be updated.

.travis.yml

@@ -10,7 +10,7 @@ env:
     - EMACS_CI=emacs-26-1
     - EMACS_CI=emacs-26-2
     - EMACS_CI=emacs-26-3
-    # - EMACS_CI=emacs-snapshot
+    - EMACS_CI=emacs-snapshot
 
 matrix:
   allow_failures:

001-setup-undercover.el

@@ -1,10 +1,11 @@
 ;; -*- mode: emacs-lisp; lexical-binding: t; no-byte-compile: t -*-
 
 
-(when (featurep 'ido-completing-read+)
-  (error "Undercover loaded too late"))
-(message "Setting up undercover")
-(require 'undercover)
-(defadvice undercover--edebug-files (before echo-instrumented-files activate)
-  (message "Undercover instrumenting the following files: %S" files))
-(undercover "ido-completing-read+.el")
+(when (version< emacs-version "27")
+  (when (featurep 'ido-completing-read+)
+    (error "Undercover loaded too late"))
+  (message "Setting up undercover")
+  (require 'undercover)
+  (defadvice undercover--edebug-files (before echo-instrumented-files activate)
+    (message "Undercover instrumenting the following files: %S" files))
+  (undercover "ido-completing-read+.el"))

Eldev

@@ -10,7 +10,8 @@
 
 (eldev-add-extra-dependencies 'test 'flx-ido)
 (eldev-add-extra-dependencies 'test 'with-simulated-input)
-(eldev-add-extra-dependencies 'test 'undercover)
+(when (version< emacs-version "27")
+  (eldev-add-extra-dependencies 'test 'undercover))
 
 ;; Tell checkdoc not to demand two spaces after a period.
 (setq sentence-end-double-space nil)