refactor(clipboard): share provider detection across y/p/paste/hist

Extracts _fish_clipboard_copy and _fish_clipboard_paste so the
wl-copy/xclip/win32yank fallback chain lives in one place instead of
four near-duplicates. hist now goes through the same chain, so it
also gets the xclip (X11) fallback it was missing before, alongside
win32yank on WSL2.

docs/manual/08-components-reference/04-c4-terminal-and-tool-integration.md

@@ -13,7 +13,7 @@ These features couple the shell to specific external tools. Disabling
     spwin                      Kitty or WezTerm
     tab                        Kitty, WezTerm, or Konsole
     split                      Kitty or WezTerm
-    hist                       fzf + wl-copy or win32yank.exe (WSL2)
+    hist                       fzf + wl-copy, xclip, or win32yank.exe (WSL2)
     logs                       fzf + ov; reads from ~/.terminal_history/
     upgrade                    paru or yay (Arch Linux only)
     WakaTime hook              wakatime CLI and a configured API key

functions/_fish_clipboard_copy.fish

@@ -0,0 +1,28 @@
+# Copyright (C) 2026 Rootiest
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+# SYNOPSIS
+#   _fish_clipboard_copy
+#
+# DESCRIPTION
+#   Copies stdin to the system clipboard. Tries wl-copy (Wayland), then
+#   xclip (X11), then win32yank.exe (WSL2).
+#
+# EXIT STATUS
+#   0  Text copied to clipboard
+#   1  No clipboard provider found
+#
+# EXAMPLE
+#   echo "hello" | _fish_clipboard_copy
+function _fish_clipboard_copy --description 'Copy stdin to the system clipboard'
+    if type -q wl-copy
+        wl-copy
+    else if type -q xclip
+        xclip -selection clipboard
+    else if type -q win32yank.exe
+        win32yank.exe -i --crlf
+    else
+        echo "Error: No clipboard provider (wl-copy, xclip, or win32yank) found." >&2
+        return 1
+    end
+end

functions/_fish_clipboard_paste.fish

@@ -0,0 +1,31 @@
+# Copyright (C) 2026 Rootiest
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+# SYNOPSIS
+#   _fish_clipboard_paste [args...]
+#
+# DESCRIPTION
+#   Prints the system clipboard contents to stdout. Tries wl-paste
+#   (Wayland), then xclip (X11), then win32yank.exe (WSL2).
+#
+# ARGUMENTS
+#   args...  Arguments forwarded to the clipboard tool
+#
+# EXIT STATUS
+#   0  Clipboard contents read successfully
+#   1  No clipboard provider found
+#
+# EXAMPLE
+#   _fish_clipboard_paste
+function _fish_clipboard_paste --description 'Print the system clipboard contents'
+    if type -q wl-paste
+        wl-paste $argv
+    else if type -q xclip
+        xclip -selection clipboard -o $argv
+    else if type -q win32yank.exe
+        win32yank.exe -o --lf $argv
+    else
+        echo "Error: No clipboard provider (wl-paste, xclip, or win32yank) found." >&2
+        return 1
+    end
+end

functions/hist.fish

@@ -12,8 +12,11 @@
 #
 # DESCRIPTION
 #   Searches fish history interactively using fzf, inserts the selected command
-#   into the command line, and copies it to the clipboard via wl-copy (falls
-#   back to win32yank on WSL2).
+#   into the command line, and copies it to the clipboard via wl-copy, xclip,
+#   or win32yank (WSL2).
+#
+# DEPENDENCIES
+#   _fish_clipboard_copy
 #
 # EXIT STATUS
 #   0  Command selected and inserted, or fzf was cancelled
@@ -37,11 +40,7 @@ function hist --description 'Search fish history and put it in the prompt'
         # Strip the timestamp for the final output
         set -l command (echo $selected | string replace -r '^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2} ' '')
 
-        if type -q wl-copy
-            echo $command | wl-copy 2>/dev/null
-        else if type -q win32yank.exe
-            echo $command | win32yank.exe -i --crlf 2>/dev/null
-        end
+        echo $command | _fish_clipboard_copy 2>/dev/null
         commandline -r $command
     end
 end

functions/p.fish

@@ -11,6 +11,9 @@
 #   Outputs clipboard contents to stdout. Uses wl-paste on Wayland, xclip on
 #   X11, or win32yank on WSL2. Supports -h/--help for usage info.
 #
+# DEPENDENCIES
+#   _fish_clipboard_paste
+#
 # ARGUMENTS
 #   -h, --help  Show usage help
 #   args...     Arguments forwarded to the clipboard tool
@@ -41,19 +44,5 @@ function p --description 'Put from clipboard'
         return 0
     end
 
-    # Determine the clipboard provider
-    set -l paste_cmd
-    if type -q wl-paste
-        set paste_cmd wl-paste
-    else if type -q xclip
-        set paste_cmd xclip -selection clipboard -o
-    else if type -q win32yank.exe
-        set paste_cmd win32yank.exe -o --lf
-    else
-        echo "Error: No clipboard provider (wl-paste, xclip, or win32yank) found." >&2
-        return 1
-    end
-
-    # Execute the paste command with any provided arguments
-    $paste_cmd $argv
+    _fish_clipboard_paste $argv
 end

functions/paste.fish

@@ -11,6 +11,9 @@
 #   Outputs clipboard contents to stdout. Uses wl-paste on Wayland, xclip on
 #   X11, or win32yank on WSL2.
 #
+# DEPENDENCIES
+#   _fish_clipboard_paste
+#
 # ARGUMENTS
 #   args...  Arguments forwarded to the clipboard tool
 #
@@ -24,14 +27,5 @@
 # EXAMPLE
 #   paste > file.txt
 function paste --description 'Paste from clipboard'
-    if type -q wl-paste
-        wl-paste $argv
-    else if type -q xclip
-        xclip -selection clipboard -o $argv
-    else if type -q win32yank.exe
-        win32yank.exe -o --lf $argv
-    else
-        echo "Error: No clipboard provider (wl-paste, xclip, or win32yank) found." >&2
-        return 1
-    end
+    _fish_clipboard_paste $argv
 end

functions/y.fish

@@ -11,6 +11,9 @@
 #   Copies text to the system clipboard using wl-copy (Wayland), xclip (X11),
 #   or win32yank (WSL2). Reads from stdin when no arguments are given.
 #
+# DEPENDENCIES
+#   _fish_clipboard_copy
+#
 # ARGUMENTS
 #   text  Text to copy; reads from stdin if omitted
 #
@@ -36,26 +39,13 @@ function y --description 'Yank to clipboard'
         return 0
     end
 
-    # Determine the clipboard provider
-    set -l copy_cmd
-    if type -q wl-copy
-        set copy_cmd wl-copy
-    else if type -q xclip
-        set copy_cmd xclip -selection clipboard
-    else if type -q win32yank.exe
-        set copy_cmd win32yank.exe -i --crlf
-    else
-        echo "Error: No clipboard provider (wl-copy, xclip, or win32yank) found." >&2
-        return 1
-    end
-
     # Handle input
     if set -q argv[1]
         # If arguments are provided, echo them to the clipboard
-        echo $argv | eval $copy_cmd
+        echo $argv | _fish_clipboard_copy
     else
         # If no arguments, read from stdin (pipes/redirects)
-        eval $copy_cmd
+        _fish_clipboard_copy
     end
 end