Add mcfly configuration to fish

.config/fish/conf.d/mcfly.fish

@@ -0,0 +1,77 @@
+#!/usr/bin/env fish
+
+# Avoid loading this file more than once
+if test "$__MCFLY_LOADED" = "loaded"
+  exit 0
+end
+set -g __MCFLY_LOADED "loaded"
+
+# Note: we only use the history file for the session when this file was sourced.
+# Would have to reset this before calling mcfly if you want commands from another session later.
+if not set -q HISTFILE
+  set -gx HISTFILE (set -q XDG_DATA_HOME; and echo $XDG_DATA_HOME; or echo $HOME/.local/share)/fish/(set -q fish_history; and echo $fish_history; or echo fish)_history
+end
+if not test -r "$HISTFILE"
+  echo "McFly: $HISTFILE does not exist or is not readable. Please fix this or set HISTFILE to something else before using McFly." >&2
+  exit 1
+end
+
+# MCFLY_SESSION_ID is used by McFly internally to keep track of the commands from a particular terminal session.
+set -gx MCFLY_SESSION_ID (dd if=/dev/urandom bs=256 count=1 2>/dev/null | env LC_ALL=C tr -dc 'a-zA-Z0-9' | head -c 24)
+
+# Find the binary
+set -q MCFLY_PATH; or set -l MCFLY_PATH (which mcfly)
+if test -z "$MCFLY_PATH"; or test "$MCFLY_PATH" = "mcfly not found"
+  echo "Cannot find the mcfly binary, please make sure that mcfly is in your path before sourcing mcfly.fish"
+  exit 1
+end
+# We don't need a MCFLY_HISTORY file because we can get the last command in fish_postexec.
+set -g __MCFLY_CMD $MCFLY_PATH --mcfly_history /dev/null --history_format fish
+
+function __mcfly_save_old_pwd -d 'Save PWD before running command' -e fish_preexec
+  set -g __MCFLY_OLD_PWD "$PWD"
+end
+
+function __mcfly_add_command -d 'Add run commands to McFly database' -e fish_postexec
+  # First, retain return code of last command before we lose it
+  set -l last_status $status
+  # Handle first call of this function after sourcing mcfly.fish, when the old PWD won't be set
+  set -q __MCFLY_OLD_PWD; or set -g __MCFLY_OLD_PWD "$PWD"
+
+  test -n "$MCFLY_DEBUG"; and echo mcfly.fish: Run eval $__MCFLY_CMD add --exit '$last_status' --old-dir '$__MCFLY_OLD_PWD' -- '$argv[1]'
+  eval $__MCFLY_CMD add --exit '$last_status' --old-dir '$__MCFLY_OLD_PWD' -- '$argv[1]'
+end
+
+# If this is an interactive shell, set up key binding functions.
+if status is-interactive
+  function __mcfly-history-widget -d "Search command history with McFly"
+    set -l mcfly_output (mktemp -t mcfly.output.XXXXXXXX)
+    eval $__MCFLY_CMD search -o '$mcfly_output' -- (commandline)
+
+    # Interpret commandline/run requests from McFly
+    set -l mode; set -l commandline
+    while read key val
+      test "$key" = "mode"; and set mode "$val"
+      test "$key" = "commandline"; and set commandline "$val"
+      test "$key" = "delete"; and history delete --exact --case-sensitive "$val"
+    end < "$mcfly_output"
+    rm -f $mcfly_output
+
+    if test -n "$commandline"
+      commandline "$commandline"
+    end
+    if test "$mode" = "run"
+      commandline -f execute
+    end
+    commandline -f repaint
+  end
+
+  function mcfly_key_bindings -d "Default key bindings for McFly"
+     bind \cr __mcfly-history-widget
+     if bind -M insert >/dev/null 2>&1
+       bind -M insert \cr __mcfly-history-widget
+     end
+  end
+
+  mcfly_key_bindings
+end