Rework to use a helper and support positional params

Author: jsotuyod

src/main/java/picocli/AutoComplete.java

@@ -422,6 +422,41 @@ private static class CommandDescriptor {
             "  done\n" +
             "  echo \"$result\"\n" +
             "}\n" +
+            "\n" +
+            "# compReplyArray generates a list of completion suggestions based on an array, ensuring all values are properly escaped.\n" +
+            "#\n" +
+            "# compReplyArray takes a single parameter: the array of options to be displayed\n" +
+            "#\n" +
+            "# The output is echoed to std_out, one option per line.\n"
+            + "#\n"
+            + "# Example usage:\n"
+            + "# local options=(\"foo\", \"bar\", \"baz\")\n"
+            + "# local IFS=$'\\n'\n"
+            + "# COMPREPLY=$(compReplyArray \"${options[@]}\")\n" +
+            "function compReplyArray() {\n" +
+            "  declare -a options\n" +
+            "  options=(\"$@\")\n" +
+            "  local curr_word=${COMP_WORDS[COMP_CWORD]}\n" +
+            "  local i\n" +
+            "  local quoted\n" +
+            "  local optionList=()\n" +
+            "\n" +
+            "  for (( i=0; i<${#options[@]}; i++ )); do\n" +
+            "    # Double escape, since we want escaped values, but compgen -W expands the argument\n" +
+            "    printf -v quoted %%q \"${options[i]}\"\n" +
+            "    quoted=\\'${quoted//\\'/\\'\\\\\\'\\'}\\'\n" +
+            "\n" +
+            "    optionList[i]=$quoted\n" +
+            "  done\n" +
+            "\n" +
+            "  # We also have to add another round of escaping to $curr_word.\n" +
+            "  curr_word=${curr_word//\\\\/\\\\\\\\}\n" +
+            "  curr_word=${curr_word//\\'/\\\\\\'}\n" +
+            "\n" +
+            "  # Actually generate completions.\n" +
+            "  local IFS=$'\\n'\n" +
+            "  echo -e \"$(compgen -W \"${optionList[*]}\" -- \"$curr_word\")\"\n" +
+            "}\n" +
             "\n";
 
     private static final String SCRIPT_FOOTER = "" +
@@ -750,9 +785,7 @@ private static String generatePositionalParamsCases(List<PositionalParamSpec> po
             int max = param.index().max();
             if (param.completionCandidates() != null) {
                 buff.append(format("%s    %s (( currIndex >= %d && currIndex <= %d )); then\n", indent, ifOrElif, min, max));
-                buff.append(format("%s      local IFS=$'\\n'\n", indent));
-                buff.append(format("%s      positionals=$( compgen -W \"${%s_pos_param_args[*]}\" -- \"%s\" )\n",
-                        indent, paramName, currWord));
+                buff.append(format("%s      positionals=$( compReplyArray \"${%s_pos_param_args[@]}\" )\n", indent, paramName, currWord));
             } else if (type.equals(File.class) || "java.nio.file.Path".equals(type.getName())) {
                 buff.append(format("%s    %s (( currIndex >= %d && currIndex <= %d )); then\n", indent, ifOrElif, min, max));
                 buff.append(format("%s      local IFS=$'\\n'\n", indent));
@@ -796,8 +829,7 @@ private static String generateOptionsCases(List<OptionSpec> argOptionFields, Str
             if (option.completionCandidates() != null) {
                 buff.append(format("%s    %s)\n", indent, concat("|", option.names()))); // "    -u|--timeUnit)\n"
                 buff.append(format("%s      local IFS=$'\\n'\n", indent));
-                buff.append(format("%s      COMPREPLY=( $( compgen -W \"${%s_option_args[*]}\" -- \"%s\" ) )\n", indent,
-                        bashify(option.paramLabel()), currWord));
+                buff.append(format("%s      COMPREPLY=( $( compReplyArray \"${%s_option_args[@]}\" ) )\n", indent, bashify(option.paramLabel()), currWord));
                 buff.append(format("%s      return $?\n", indent));
                 buff.append(format("%s      ;;\n", indent));
             } else if (type.equals(File.class) || "java.nio.file.Path".equals(type.getName())) {