CCU: check if fields exist before manipulating them

this avoids javascript errors of object not found when
switching between form types that don't have all the fields
displayed.

resources/celerity/map.php

@@ -516,7 +516,7 @@ return array(
     'rsrc/js/core/phtize.js' => '2f1db1ed',
     'rsrc/js/extensions/choices/choices.css' => 'efe1d093',
     'rsrc/js/extensions/choices/choices.js' => '3f23770b',
-    'rsrc/js/extensions/snipe-fields-validation.js' => '057d79f6',
+    'rsrc/js/extensions/snipe-fields-validation.js' => 'ea38591d',
     'rsrc/js/phui/behavior-phui-dropdown-menu.js' => '5cf0501a',
     'rsrc/js/phui/behavior-phui-file-upload.js' => 'e150bd50',
     'rsrc/js/phui/behavior-phui-selectable-list.js' => 'b26a41e4',
@@ -911,7 +911,7 @@ return array(
     'releeph-request-differential-create-dialog' => '0ac1ea31',
     'releeph-request-typeahead-css' => 'bce37359',
     'setup-issue-css' => '5eed85b2',
-    'snipe-fields-validation-js' => '057d79f6',
+    'snipe-fields-validation-js' => 'ea38591d',
     'sprite-login-css' => '18b368a6',
     'sprite-tokens-css' => 'f1896dc5',
     'syntax-default-css' => '055fc231',

webroot/rsrc/js/extensions/snipe-fields-validation.js

@@ -220,9 +220,11 @@ function fetch_and_hide_extra_assets_elements(index, unique_items) {
     asset["asset_tag_parent"].classList.add("snipe_property");
   }
 
-  asset["item_owner_parent"] = document.getElementsByName(
-    "std:maniphest:purchasing:item-owner" + index
-  )[0].parentNode.parentNode;
+  if (document.getElementsByName("std:maniphest:purchasing:item-owner" + index).length > 0) {
+    asset["item_owner_parent"] = document.getElementsByName(
+      "std:maniphest:purchasing:item-owner" + index
+    )[0].parentNode.parentNode;
+  }
   asset["item_owner_parent"].classList.add("snipe_property");
 
   asset["model_parent"] = document.getElementsByName(
@@ -236,20 +238,24 @@ function fetch_and_hide_extra_assets_elements(index, unique_items) {
   asset["quantity"] = document.getElementsByName(
     "std:maniphest:purchasing:quantity" + index
   )[0].parentNode.parentNode;
-  asset["country_of_origin_parent"] = document.getElementsByName(
-    "std:maniphest:purchasing:country-origin" + index
-  )[0].parentNode.parentNode;
+  if (document.getElementsByName("std:maniphest:purchasing:country-origin" + index).length > 0) {
+    asset["country_of_origin_parent"] = document.getElementsByName(
+      "std:maniphest:purchasing:country-origin" + index
+    )[0].parentNode.parentNode;
+  }
   asset["asset_cost_parent"] = document.getElementsByName(
     "std:maniphest:purchasing:expected-cost" + index
   )[0].parentNode.parentNode;
-
-  asset["asset_link_parent"] = document.getElementsByName(
-    "std:maniphest:purchasing:item-link" + index
-  )[0].parentNode.parentNode;
-
-  asset["asset_currency_parent"] = document.getElementsByName(
-    "std:maniphest:purchasing:currency" + index
-  )[0].parentNode.parentNode;
+  if (document.getElementsByName("std:maniphest:purchasing:item-link" + index).length > 0) {
+    asset["asset_link_parent"] = document.getElementsByName(
+      "std:maniphest:purchasing:item-link" + index
+    )[0].parentNode.parentNode;
+  };
+  if (document.getElementsByName("std:maniphest:purchasing:currency" + index).length > 0) {
+    asset["asset_currency_parent"] = document.getElementsByName(
+      "std:maniphest:purchasing:currency" + index
+    )[0].parentNode.parentNode;
+  };
   if (document.getElementsByName("std:maniphest:purchasing:serial" + index).length > 0) {
     asset["asset_serial_parent"] = document.getElementsByName(
       "std:maniphest:purchasing:serial" + index
@@ -330,6 +336,9 @@ function purchasing_validations() {
     }
   };
 
+  if (document.getElementsByName("__submit__").length === 0) {
+    return;
+  }
   submit_parent = document.getElementsByName("__submit__")[0].parentNode
     .parentNode;
   add_new_asset = document.createElement("div");
@@ -340,6 +349,9 @@ function purchasing_validations() {
 
   add_new_asset_btn.onclick = function (e) {
     e.preventDefault();
+    if (!num_asset_forms.value) {
+      num_asset_forms.value = 1;
+    };
     if (num_asset_forms.value < MAX_ALLOWED_ASSETS) {
       for (let key in assets_list[num_asset_forms.value - 1]) {
         if (