fix(cd): fix cdable_vars overwritten by another generator

bash_completion

@@ -863,7 +863,16 @@ if ((BASH_VERSINFO[0] > 5 || BASH_VERSINFO[0] == 5 && BASH_VERSINFO[1] >= 3)); t
         [[ $_dir ]] && command cd -- "$_original_pwd"
 
         ((${#_upvars[@]})) && _comp_unlocal "${_upvars[@]}"
-        ((${#_result[@]})) || return
+
+        # workaround for bash-4.2 nounset
+        ((${#_result[@]})) || {
+            if [[ $_append ]]; then
+                eval -- "$_var+=()"
+            else
+                eval -- "$_var=()"
+            fi
+            return
+        }
 
         if [[ $_prefix ]]; then
             local _i

completions/cd

@@ -39,13 +39,13 @@ _comp_cmd_cd__compgen_cdpath()
     _comp_split -F : paths "$CDPATH"
     for _p in "${paths[@]}"; do
         # create an array of matched subdirs
-        _comp_compgen -v dirs -c "$_p/$cur" -- -d
-        for _d in "${dirs[@]}"; do
-            if [[ ($_mark_symdirs && -L $_d || $_mark_dirs && ! -L $_d) && ! -d ${_d#"$_p/"} ]]; then
-                _d+="/"
-            fi
-            _cdpaths+=("${_d#"$_p/"}")
-        done
+        _comp_compgen -v dirs -c "$_p/$cur" -- -d &&
+            for _d in "${dirs[@]}"; do
+                if [[ ($_mark_symdirs && -L $_d || $_mark_dirs && ! -L $_d) && ! -d ${_d#"$_p/"} ]]; then
+                    _d+="/"
+                fi
+                _cdpaths+=("${_d#"$_p/"}")
+            done
     done
     _comp_unlocal paths dirs
 
@@ -56,7 +56,8 @@ _comp_cmd_cd__compgen_cdpath()
         fi
     fi
 
-    _comp_compgen_set "${_cdpaths[@]}"
+    ((${#_cdpaths[@]})) &&
+        _comp_compgen_set "${_cdpaths[@]}"
 }
 
 _comp_cmd_cd()
@@ -72,7 +73,7 @@ _comp_cmd_cd()
 
     compopt -o filenames
     _comp_cmd_cd__compgen_cdable_vars
-    _comp_cmd_cd__compgen_cdpath
+    _comp_compgen -ai cd cdpath
     _comp_compgen -a filedir -d
 }
 complete -F _comp_cmd_cd -o nospace cd pushd

test/t/test_cd.py

@@ -42,3 +42,12 @@ def test_cdable_vars(self, bash):
             bash_env.write_variable("foo6", "shared/default/bar")
             completion = assert_complete(bash, "cd f")
             assert completion == ["foo1", "foo2"]
+
+    def test_cdable_vars_2(self, bash):
+        with bash_env_saved(bash) as bash_env:
+            bash_env.write_variable("CDPATH", "nonexistent")
+            bash_env.shopt("cdable_vars", True)
+            bash_env.write_variable("foo1", "shared")
+            bash_env.write_variable("foo2", "shared/default")
+            completion = assert_complete(bash, "cd f")
+            assert completion == ["foo1", "foo2"]