diff --git a/utbot-js/src/main/kotlin/api/JsTestGenerator.kt b/utbot-js/src/main/kotlin/api/JsTestGenerator.kt
index a72adaaa82..d008ed1391 100644
--- a/utbot-js/src/main/kotlin/api/JsTestGenerator.kt
+++ b/utbot-js/src/main/kotlin/api/JsTestGenerator.kt
@@ -113,7 +113,7 @@ class JsTestGenerator(
         )
         context.packageJson = PackageJsonService(
             sourceFilePath,
-            projectPath,
+            File(projectPath),
         ).findClosestConfig()
         val paramNames = mutableMapOf<ExecutableId, List<String>>()
         val testSets = mutableListOf<CgMethodTestSet>()
diff --git a/utbot-js/src/main/kotlin/service/PackageJsonService.kt b/utbot-js/src/main/kotlin/service/PackageJsonService.kt
index 1d5d04a2b2..3a2dac9a72 100644
--- a/utbot-js/src/main/kotlin/service/PackageJsonService.kt
+++ b/utbot-js/src/main/kotlin/service/PackageJsonService.kt
@@ -15,20 +15,20 @@ data class PackageJson(
 
 class PackageJsonService(
     private val filePathToInference: String,
-    private val projectPath: String
+    private val projectDir: File
 ) {
 
     fun findClosestConfig(): PackageJson {
-        var currDir = File(filePathToInference.substringBeforeLast("/"))
+        var currDir = File(filePathToInference)
         do {
+            currDir = currDir.parentFile
             val matchingFiles: Array<File> = currDir.listFiles(
                 FilenameFilter { _, name ->
                     return@FilenameFilter name == "package.json"
                 }
             ) ?: throw IllegalStateException("Error occurred while scanning file system")
             if (matchingFiles.isNotEmpty()) return parseConfig(matchingFiles.first())
-            currDir = currDir.parentFile
-        } while (currDir.path != projectPath)
+        } while (currDir != projectDir)
         return PackageJson.defaultConfig
     }
 
diff --git a/utbot-js/src/main/kotlin/settings/JsPackagesSettings.kt b/utbot-js/src/main/kotlin/settings/JsPackagesSettings.kt
index 3da41c4387..ebea20a6ab 100644
--- a/utbot-js/src/main/kotlin/settings/JsPackagesSettings.kt
+++ b/utbot-js/src/main/kotlin/settings/JsPackagesSettings.kt
@@ -1,5 +1,6 @@
 package settings
 
+import java.io.File
 import org.utbot.common.PathUtil.replaceSeparator
 import service.PackageJsonService
 import settings.JsPackagesSettings.mochaData
@@ -51,7 +52,7 @@ class PackageDataService(
     private val projectPath: String,
     private val pathToNpm: String,
 ) {
-    private val packageJson = PackageJsonService(filePathToInference, projectPath).findClosestConfig()
+    private val packageJson = PackageJsonService(filePathToInference, File(projectPath)).findClosestConfig()
 
     companion object {
         var nycPath: String = ""