diff --git a/npm_and_yarn/lib/dependabot/npm_and_yarn/file_parser.rb b/npm_and_yarn/lib/dependabot/npm_and_yarn/file_parser.rb
index 7f42984598a..2873648c01d 100644
--- a/npm_and_yarn/lib/dependabot/npm_and_yarn/file_parser.rb
+++ b/npm_and_yarn/lib/dependabot/npm_and_yarn/file_parser.rb
@@ -89,6 +89,8 @@ def ecosystem
         )
       end
 
+      private
+
       sig { returns(PackageManagerHelper) }
       def package_manager_helper
         @package_manager_helper ||= T.let(
@@ -108,8 +110,6 @@ def lockfiles
         }
       end
 
-      private
-
       sig { returns(T.untyped) }
       def parsed_package_json
         JSON.parse(T.must(package_json.content))
@@ -119,33 +119,39 @@ def parsed_package_json
 
       sig { returns(Dependabot::DependencyFile) }
       def package_json
-        @package_json ||= T.let(T.must(get_original_file("package.json")), T.nilable(Dependabot::DependencyFile))
+        # Declare the instance variable with T.let and the correct type
+        @package_json ||= T.let(
+          T.must(dependency_files.find { |f| f.name == "package.json" }),
+          T.nilable(Dependabot::DependencyFile)
+        )
       end
 
       sig { returns(T.nilable(Dependabot::DependencyFile)) }
       def shrinkwrap
-        @shrinkwrap ||= T.let(
-          get_original_file("npm-shrinkwrap.json") || get_original_file("package-lock.json"),
-          T.nilable(Dependabot::DependencyFile)
-        )
+        @shrinkwrap ||= T.let(dependency_files.find do |f|
+          f.name == "npm-shrinkwrap.json"
+        end, T.nilable(Dependabot::DependencyFile))
       end
 
       sig { returns(T.nilable(Dependabot::DependencyFile)) }
       def package_lock
-        @package_lock ||= T.let(
-          get_original_file("package-lock.json") || get_original_file("npm-shrinkwrap.json"),
-          T.nilable(Dependabot::DependencyFile)
-        )
+        @package_lock ||= T.let(dependency_files.find do |f|
+          f.name == "package-lock.json"
+        end, T.nilable(Dependabot::DependencyFile))
       end
 
       sig { returns(T.nilable(Dependabot::DependencyFile)) }
       def yarn_lock
-        @yarn_lock ||= T.let(get_original_file("yarn.lock"), T.nilable(Dependabot::DependencyFile))
+        @yarn_lock ||= T.let(dependency_files.find do |f|
+          f.name == "yarn.lock"
+        end, T.nilable(Dependabot::DependencyFile))
       end
 
       sig { returns(T.nilable(Dependabot::DependencyFile)) }
       def pnpm_lock
-        @pnpm_lock ||= T.let(get_original_file("pnpm-lock.yaml"), T.nilable(Dependabot::DependencyFile))
+        @pnpm_lock ||= T.let(dependency_files.find do |f|
+          f.name == "pnpm-lock.yaml"
+        end, T.nilable(Dependabot::DependencyFile))
       end
 
       sig { returns(Dependabot::FileParsers::Base::DependencySet) }