From 47dd1f74bf5f8bb2ec9d2ec67566f0b04ed1c30a Mon Sep 17 00:00:00 2001
From: Finley Garton <finley.garton@starlingbank.com>
Date: Fri, 8 Sep 2023 17:37:52 +0100
Subject: [PATCH] set to undefined rather than empty string

---
 dist/index.js       | 5 ++++-
 src/input-helper.ts | 6 +++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/dist/index.js b/dist/index.js
index 52f21e4..ddf2b3d 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -1728,7 +1728,10 @@ function getInputs() {
         result.clean = (core.getInput('clean') || 'true').toUpperCase() === 'TRUE';
         core.debug(`clean = ${result.clean}`);
         // Filter
-        result.filter = core.getInput('filter');
+        const filter = core.getInput('filter');
+        if (filter) {
+            result.filter = filter;
+        }
         core.debug(`filter = ${result.filter}`);
         // Sparse checkout
         const sparseCheckout = core.getMultilineInput('sparse-checkout');
diff --git a/src/input-helper.ts b/src/input-helper.ts
index 6626979..e546c19 100644
--- a/src/input-helper.ts
+++ b/src/input-helper.ts
@@ -83,7 +83,11 @@ export async function getInputs(): Promise<IGitSourceSettings> {
   core.debug(`clean = ${result.clean}`)
 
   // Filter
-  result.filter = core.getInput('filter')
+  const filter = core.getInput('filter')
+  if (filter) {
+    result.filter = filter
+  }
+
   core.debug(`filter = ${result.filter}`)
 
   // Sparse checkout