diff --git a/test/index.js b/test/index.js
index 8f8ea37cd..2f0933658 100644
--- a/test/index.js
+++ b/test/index.js
@@ -35,15 +35,17 @@ const path = require('path');
 let filterCondition = process.env.npm_config_filter || '';
 let filterConditionFiles = [];
 
-if (process.env.npm_config_filter !== null && process.env.npm_config_filter !== undefined && process.env.npm_config_filter.trim() !== '') {
+if (filterCondition !== '') {
   filterCondition = require('../unit-test/matchModules').matchWildCards(process.env.npm_config_filter);
-  filterConditionFiles = filterCondition.split(' ').length ? filterCondition.split(' ') : [filterCondition];
+  filterConditionFiles = filterCondition.split(' ').length > 0 ? filterCondition.split(' ') : [filterCondition];
 }
 
+const filterConditionsProvided = filterConditionFiles.length > 0;
+
 function checkFilterCondition (fileName, parsedFilepath) {
   let result = false;
 
-  if (!filterConditionFiles.length) result = true;
+  if (!filterConditionsProvided) return true;
   if (filterConditionFiles.includes(parsedFilepath)) result = true;
   if (filterConditionFiles.includes(fileName)) result = true;
   return result;
@@ -108,7 +110,7 @@ if (napiVersion < 3) {
   testModules.splice(testModules.indexOf('version_management'), 1);
 }
 
-if (napiVersion < 4 && !filterConditionFiles.length) {
+if (napiVersion < 4 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('asyncprogressqueueworker'), 1);
   testModules.splice(testModules.indexOf('asyncprogressworker'), 1);
   testModules.splice(testModules.indexOf('threadsafe_function/threadsafe_function_ctx'), 1);
@@ -119,30 +121,30 @@ if (napiVersion < 4 && !filterConditionFiles.length) {
   testModules.splice(testModules.indexOf('threadsafe_function/threadsafe_function'), 1);
 }
 
-if (napiVersion < 5 && !filterConditionFiles.length) {
+if (napiVersion < 5 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('date'), 1);
 }
 
-if (napiVersion < 6 && !filterConditionFiles.length) {
+if (napiVersion < 6 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('addon'), 1);
   testModules.splice(testModules.indexOf('addon_data'), 1);
   testModules.splice(testModules.indexOf('bigint'), 1);
   testModules.splice(testModules.indexOf('typedarray-bigint'), 1);
 }
 
-if (majorNodeVersion < 12 && !filterConditionFiles.length) {
+if (majorNodeVersion < 12 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('objectwrap_worker_thread'), 1);
   testModules.splice(testModules.indexOf('error_terminating_environment'), 1);
 }
 
-if (napiVersion < 8 && !filterConditionFiles.length) {
+if (napiVersion < 8 && !filterConditionsProvided) {
   testModules.splice(testModules.indexOf('object/object_freeze_seal'), 1);
 }
 
 (async function () {
   console.log(`Testing with Node-API Version '${napiVersion}'.`);
 
-  if (filterConditionFiles.length) { console.log('Starting test suite\n', testModules); } else { console.log('Starting test suite\n'); }
+  if (filterConditionsProvided) { console.log('Starting test suite\n', testModules); } else { console.log('Starting test suite\n'); }
 
   // Requiring each module runs tests in the module.
   for (const name of testModules) {