Fix Klipper methods.

pyperclip/clipboards.py

@@ -83,6 +83,9 @@ def paste_xsel():
 
 def init_klipper_clipboard():
     def copy_klipper(text):
+        if text is '':
+            return
+
         p = subprocess.Popen(
             ['qdbus', 'org.kde.klipper', '/klipper', 'setClipboardContents', text.encode('utf-8')],
             stdin=subprocess.PIPE,
@@ -96,23 +99,33 @@ def paste_klipper():
             stdout=subprocess.PIPE,
             close_fds=True
         )
+        # Obtain the version from the cli bin.
+        version = Popen(['klipper', '--version'], stdout=PIPE, close_fds=True)
+
+        version = version.communicate(input=None)
+        version = version[0]
+        version = version[8:] # Remove klipper from the string.
+        version = version[:-1] # Remove \n from the string.
+
         stdout, stderr = p.communicate()
+
+        if version == '0.20.3' or version == '0.9.7':
+            return _klipper_fix_newline(stdout.decode('utf-8'))
 
-        # Apparently Klipper has a bug that adds a newline to the end. It was reported in Klipper version 0.20.3 but I've
-        # seen it in 0.9.7. The bug is unfixed. This function will remove a newline if the string has one.
-        # TODO: In the future, once Klipper is fixed, check the version number to decided whether or not to strip the
-        # newline.
-        # https://bugs.kde.org/show_bug.cgi?id=342874
-
-        clipboardContents = stdout.decode('utf-8')
-        assert len(clipboardContents) > 0  # even if blank, Klipper will append a newline at the end
-        assert clipboardContents[-1] == '\n'  # make sure that newline is there
-        if len(clipboardContents) and clipboardContents[-1] == '\n':
-            clipboardContents = clipboardContents[:-1]
-        return clipboardContents
+        return stdout.decode('utf-8')
 
     return copy_klipper, paste_klipper
 
+def _klipper_fix_newline(text):
+    # Apparently Klipper has a bug that adds a newline to the end. It was reported in Klipper version 0.20.3 but I've
+    # seen it in 0.9.7. The bug is unfixed. This function will remove a newline if the string has one.
+    # https://bugs.kde.org/show_bug.cgi?id=342874
+
+    clipboardContents = text
+    if len(clipboardContents) and clipboardContents[-1] == '\n':
+        clipboardContents = clipboardContents[:-1]
+    return clipboardContents
+
 
 def init_no_clipboard():
     class ClipboardUnavailable(object):