Implement unix_filename_rubout.

unix_filename_rubout deletes to the previous slash or whitespace,
unlike the previously implemented backwards-kill-word which treats and
non-alphanumeric character as a boundary.

To illustrate, given the text 'foo/bar.baz', unix_filename_rubout will
delete 'bar.baz' while backwards-kill-word will delete only 'baz'.

See #1710.

qutebrowser/misc/readline.py

@@ -148,14 +148,8 @@ class ReadlineBridge:
         self._deleted[widget] = widget.selectedText()
         widget.del_()
 
-    @cmdutils.register(instance='readline-bridge', hide=True,
-                       modes=[typ.KeyMode.command, typ.KeyMode.prompt])
-    def rl_unix_word_rubout(self):
-        """Remove chars from the cursor to the beginning of the word.
-
-        This acts like readline's unix-word-rubout. Whitespace is used as a
-        word delimiter.
-        """
+    def _rubout(self, delim):
+        """Delete backwards using the characters in delim as boundaries."""
         widget = self._widget()
         if widget is None:
             return
@@ -164,14 +158,14 @@ class ReadlineBridge:
 
         target_position = cursor_position
 
-        is_word_boundary = True
-        while is_word_boundary and target_position > 0:
-            is_word_boundary = text[target_position - 1] == " "
+        is_boundary = True
+        while is_boundary and target_position > 0:
+            is_boundary = text[target_position - 1] in delim
             target_position -= 1
 
-        is_word_boundary = False
-        while not is_word_boundary and target_position > 0:
-            is_word_boundary = text[target_position - 1] == " "
+        is_boundary = False
+        while not is_boundary and target_position > 0:
+            is_boundary = text[target_position - 1] in delim
             target_position -= 1
 
         moveby = cursor_position - target_position - 1
@@ -179,6 +173,25 @@ class ReadlineBridge:
         self._deleted[widget] = widget.selectedText()
         widget.del_()
 
+    @cmdutils.register(instance='readline-bridge', hide=True,
+                       modes=[typ.KeyMode.command, typ.KeyMode.prompt])
+    def rl_unix_word_rubout(self):
+        """Remove chars from the cursor to the beginning of the word.
+
+        This acts like readline's unix-word-rubout. Whitespace is used as a
+        word delimiter.
+        """
+        self._rubout([' '])
+
+    @cmdutils.register(instance='readline-bridge', hide=True,
+                       modes=[typ.KeyMode.command, typ.KeyMode.prompt])
+    def rl_unix_filename_rubout(self):
+        """Remove chars from the cursor to the previous path separator.
+
+        This acts like readline's unix-filename-rubout.
+        """
+        self._rubout([' ', '/'])
+
     @cmdutils.register(instance='readline-bridge', hide=True,
                        modes=[typ.KeyMode.command, typ.KeyMode.prompt])
     def rl_backward_kill_word(self):

tests/unit/misc/test_readline.py

@@ -250,6 +250,24 @@ def test_rl_unix_word_rubout(lineedit, bridge, text, deleted, rest):
     assert lineedit.aug_text() == deleted + '|'
 
 
+@pytest.mark.parametrize('text, deleted, rest', [
+    ('test delete|foobar', 'delete', 'test |foobar'),
+    ('test delete |foobar', 'delete ', 'test |foobar'),
+    ('open -t github.com/foo/bar  |', 'bar  ', 'open -t github.com/foo/|'),
+    ('open -t |github.com/foo/bar', '-t ', 'open |github.com/foo/bar'),
+    ('open foo/bar.baz|', 'bar.baz', 'open foo/|'),
+])
+def test_rl_unix_filename_rubout(lineedit, bridge, text, deleted, rest):
+    """Delete filename segment and see if it comes back with yank."""
+    lineedit.set_aug_text(text)
+    bridge.rl_unix_filename_rubout()
+    assert bridge._deleted[lineedit] == deleted
+    assert lineedit.aug_text() == rest
+    lineedit.clear()
+    bridge.rl_yank()
+    assert lineedit.aug_text() == deleted + '|'
+
+
 @pytest.mark.parametrize('text, deleted, rest', [
     fixme(('test foobar| delete', ' delete', 'test foobar|')),
     ('test foobar| delete', ' ', 'test foobar|delete'),  # wrong
@@ -276,6 +294,7 @@ def test_rl_kill_word(lineedit, bridge, text, deleted, rest):
     ('open -t |github.com/foo/bar', 't ', 'open -|github.com/foo/bar'),
     fixme(('test del<ete>foobar', 'delete', 'test |foobar')),
     ('test del<ete >foobar', 'del', 'test |ete foobar'),  # wrong
+    ('open foo/bar.baz|', 'baz', 'open foo/bar.|'),
 ])
 def test_rl_backward_kill_word(lineedit, bridge, text, deleted, rest):
     """Delete to word beginning and see if it comes back with yank."""