prompt: Update, test select_option validation err

Author: mbland

lib/prompt

@@ -30,7 +30,7 @@
 # Returns:
 #   zero if `result_var` contains the user's selection, nonzero otherwise
 @go.select_option() {
-  @go.validate_identifier_or_die 'Result variable name' "$1"
+  @go.validate_identifier_or_die 'Input selection variable name' "$1"
 
   local __go_selected_option
   select __go_selected_option in "${@:2}"; do

tests/prompt/select-option.bats

@@ -18,6 +18,20 @@ teardown() {
   @go.remove_test_go_rootdir
 }
 
+@test "$SUITE: error if selection variable not a valid identifier" {
+  @go.create_test_go_script '. "$_GO_USE_MODULES" "prompt"' \
+    '@go.select_option "invalid;"'
+
+  run "$TEST_GO_SCRIPT"
+  assert_failure
+
+  local err_msg='Input selection variable name "invalid;" for '
+  err_msg+='@go.select_option contains invalid identifier characters at:'
+
+  assert_lines_match "^${err_msg}\$" \
+    "^  $TEST_GO_SCRIPT:[0-9] main$"
+}
+
 @test "$SUITE: no options exits instantly" {
   run "$TEST_GO_SCRIPT"
   assert_failure ''