fish: Use primary selection

.config/fish/functions/fish_primary_copy.fish

@@ -0,0 +1,7 @@
+function fish_primary_copy
+    if type -q pbcopy
+        commandline | pbcopy
+    else if type -q xsel
+        commandline | xsel
+    end
+end

.config/fish/functions/fish_primary_paste.fish

@@ -0,0 +1,29 @@
+function fish_primary_paste
+    set -l data
+    if type -q pbpaste
+        set data (pbpaste)
+    else if type -q xsel
+        # Return if `xsel` failed.
+        # That way any xsel error is printed (to show e.g. a non-functioning X connection),
+        # but we don't print the redundant (and overly verbose for this) commandline error.
+        # Also require non-empty contents to not clear the buffer.
+        if not set data (xsel)
+            return 1
+        end
+    end
+    # Also split on \r to turn it into a newline,
+    # otherwise the output looks really confusing.
+    set data (string split \r -- $data)
+
+    # If the current token has an unmatched single-quote,
+    # escape all single-quotes (and backslashes) in the paste,
+    # in order to turn it into a single literal token.
+    #
+    # This eases pasting non-code (e.g. markdown or git commitishes).
+    if __fish_commandline_is_singlequoted
+        set data (string replace -ra "(['\\\])" '\\\\\\\$1' -- $data)
+    end
+    if test -n "$data"
+        commandline -i -- $data
+    end
+end

.config/fish/functions/fish_user_key_bindings.fish

@@ -11,6 +11,9 @@ function fish_user_key_bindings
 	bind -M insert \ce edit_command_buffer
 	bind -m insert \ce edit_command_buffer
 
+	bind \cv fish_primary_paste
+	bind \cx fish_primary_copy
+
 	## fzf
 	if type -pq fzf
 		source $fish_config_path/fzf.fish