Add tab completion for cd aliases.

* README.md: Documented.

* cdlog.sh (cdlog.complete): Completion function that
completes on directories, including CDPATH,
as well as cdlog's cd aliases.
(toplevel): Register the completion function.

2 files changed, 35 insertions, 0 deletions

diff --git a/README.md b/README.md
index 8c54ac4..2a248f1 100644
--- a/README.md
+++ b/README.md
@@ -105,6 +105,12 @@ the FIFO.
 LRU mode keeps duplicate directories out of the FIFO and while
 promoting recently used directories toward the top.
 
+## Completion
+
+`cdlog` provides its own Tab completion for the `cd` command, overriding
+the built-in completion. It includes the cd aliases, while completing
+on directories, taking into account `CDPATH`.
+
 ## How is this better?
 
 * It's not hard-coded C code inside the shell; it consists of a small amount of
diff --git a/cdlog.sh b/cdlog.sh
index b7d814d..fd1b220 100644
--- a/cdlog.sh
+++ b/cdlog.sh
@@ -337,6 +337,33 @@ cdlog.alias()
   return 0
 }
 
+# Tab completion for cd aliases
+
+cdlog.complete()
+{
+  COMPREPLY=()
+  local cur=${COMP_WORDS[COMP_CWORD]}
+  local alias
+  local dir
+
+  COMPREPLY+=( $(compgen -d -- "$cur") )
+
+  for alias in "${!cdlog_alias[@]}"; do
+    case "$alias" in
+    ( "$cur"* )
+      COMPREPLY+=( "$alias" )
+      ;;
+    esac
+  done
+
+  IFS=':' set -- $CDPATH
+  for dir in "$@"; do
+    COMPREPLY+=( $(compgen -d -- "$dir/$cur") )
+  done
+
+  return  0
+}
+
 # Aliases.
 alias cd='cdlog.chdir -P'
 alias pd='cdlog.pop'
@@ -359,6 +386,8 @@ if [ -z "$c1" -o -z "$cdlog_dirs" ] ; then
   cdlog.init
 fi
 
+# Register completion
+complete -F cdlog.complete cd
 
 # Copyright 2024
 # Kaz Kylheku <kaz@kylheku.com>