[fish] Unescape query from commandline (junegunn#4236)

More natural processing of the query taken from command line, by
unquoting/unescaping the token. Unescaped open quotes are removed.
Because of how `string unescape` works, if both single and double quotes
are present, with the outer quotes open, only the outer quotes are
removed.

Examples:
`'foo bar'`, `"foo bar"`, `foo\ bar` becomes `foo bar`
`"foobar`, `'foobar`, `foo"bar`, `foo'bar` becomes `foobar`
`'"foo"'`, `'"foo"` becomes `"foo"`
`"'foo'"`, `"'foo'` becomes `'foo'`
`"'foo` becomes `'foo`
`'"foo` becomes `"foo`

Author: bitraid

shell/key-bindings.fish

@@ -154,8 +154,8 @@ function fzf_key_bindings
     # eval is used to do shell expansion on paths
     eval set commandline $commandline
 
-    # Combine multiple consecutive slashes into one
-    set commandline (string replace -r -a -- '/+' '/' $commandline)
+    # Combine multiple consecutive slashes into one, and unescape.
+    set commandline (string replace -r -a -- '/+' '/' $commandline | string unescape -n)
 
     if test -z "$commandline"
       # Default to current directory with no --query
@@ -171,10 +171,8 @@ function fzf_key_bindings
         # if $dir is "." but commandline is not a relative path, this means no file path found
         set fzf_query $commandline
       else
-        # Special characters must be double escaped.
-        set -l re_dir (string escape -n -- $dir)
         # Also remove trailing slash after dir, to "split" input properly
-        set fzf_query (string replace -r -- "^$re_dir/?" '' $commandline)
+        set fzf_query (string replace -r -- "^$dir/?" '' $commandline)
       end
     end
 
@@ -184,7 +182,7 @@ function fzf_key_bindings
   end
 
   function __fzf_get_dir -d 'Find the longest existing filepath from input string'
-    set dir (string unescape -n -- $argv)
+    set dir $argv
 
     # Strip trailing slash, unless $dir is root dir (/)
     set dir (string replace -r -- '(?<!^)/$' '' $dir)