Add _prepend_tree command. Traverse a dependency tree and add it to a path.

functions/_prepend_tree.fish

@@ -0,0 +1,129 @@
+#
+# NAME
+#      _prepend_tree - add a dependency tree to a path
+#
+# SYNOPSIS
+#      _prepend_tree [-P --preview] <source path> [<glob>..]
+#                    [-d --destination <destination path>]
+#
+# DESCRIPTION
+#      Traverse the source path and prepend each directory matching the
+#      glob list to the destination path or to the FISH function path.
+#      If no globs are specified, match any directories with `.fish`
+#      files. Return 1 if the source path is not specified.
+#
+# OPTIONS
+#      <SOURCE PATH>
+#          Required. Specify the path to find glob matches to prepend
+#          to the destination path.
+#
+#      <glob>...
+#          Glob pattern to match when traversing the source path. If a
+#          directory is found, it is prepended to the destination path.
+#          `.fish` is assumed by default if not globs are specified.
+#
+#          It is also possible to use logical OR / AND operators to list
+#          multiple globs. If none is used, OR is assumed by default.
+#          The OR operator
+
+#
+#          The following operators are available:
+#
+#             ! -not
+#                 Negates the following exression.
+#
+#                     ! glob1 glob2   →  NOT glob1 or glob2
+#
+#             -o -or
+#                 Any matches should meet at least one listed criteria.
+#
+#                     glob1 -o glob2  →  glob1 OR glob2
+#
+#             -a -and
+#                 Any matches must meet all listed criteria.
+#
+#                     glob1 -a glob2  →  glob1 AND glob2
+#
+#      -d <DESTINATION PATH>
+#          Should appear at the end if used. Specifies the name of the
+#          global path variable to prepend the matched directories to.
+#          If not used, the $fish_function_path is assumed by default.
+#
+# EXAMPLES
+#      _prepend_tree $lib_path
+#          Prepends all directories inside $lib_path containing `.fish`
+#          files to $fish_function_path.
+#
+#      _prepend_tree $lib_path -d PATH
+#          Prepends all directories inside $lib_path containing .fish
+#          files to a global variable named PATH.
+#
+#      _prepend_tree $lib_path \*.fish \*.sh
+#          Prepends sub directories with either `.fish` OR `.sh` files.
+#
+#      _prepend_tree $lib_path \*.css -a ! _\*.\* -d PATH
+#          Prepends sub directories that have `.css` extension, but do
+#          not start with `_`.
+#
+# AUTHORS
+#      Jorge Bucaran <jbucaran@me.com>
+#
+# SEE ALSO
+#      .oh-my-fish/functions/_prepend_path.fish
+#
+# v.0.1.0
+#/
+function _prepend_tree -d "Load a dependency tree, matching `.fish` files by default."
+  set -l source
+  set -l destination fish_function_path
+  set -l glob
+  set -l depth 1
+  set -l len (count $argv)
+
+  [ $len -gt 0 ]
+    and set source $argv[1]
+    or return 1
+
+  [ $len -gt 0 ]
+    and set source $argv[1]
+    or return 1
+
+  if [ $len -gt 2 ]
+  # At least 3 arguments must exist
+  # to use the destination path.
+    switch $argv[-2]
+      case -d --destination
+        set destination $argv[-1]
+    end
+  end
+
+  if [ $len -gt 1 ]
+    set -l operator
+    for match in $argv[2..-1]
+      switch $match
+        case ! -not
+          set operator $operator !
+        case -o -or
+          set operator -o
+        case -a -and
+          set operator -a
+        case -d --destination
+          break # No more globs after this point.
+        case "*"
+          [ operator = ! ]
+            and set glob $operator $glob
+            or set glob $glob $operator
+          set glob $glob -name $match
+          set operator -o
+      end
+    end
+  end
+
+  [ -z "$glob" ]
+    and set glob -name \*.fish
+
+  for directory in $source/**/
+    [ -z (find $directory $glob -maxdepth $depth | head -1) ]
+      or _prepend_path $directory $destination
+  end
+end