diff --git a/Formula/crab_share.rb b/Formula/crab_share.rb
index c6f5dbd..5253682 100644
--- a/Formula/crab_share.rb
+++ b/Formula/crab_share.rb
@@ -2,8 +2,8 @@ class CrabShare < Formula
   desc "Simple application to upload files to an S3 bucket and receive a shareable link"
   homepage "https://github.com/lounge-rocks/crab_share"
 
-  url "https://github.com/lounge-rocks/crab_share/archive/refs/tags/0.3.0.tar.gz"
-  sha256 "fccdb99d1fed40ea1115dc20bf080f8eff8494ff50890860ada89042b00e2bbf"
+  url "https://github.com/lounge-rocks/crab_share/archive/refs/tags/0.3.1.tar.gz"
+  sha256 "359f74a6eddf80df1646ab8c6fba48db9606e4ba939f2b569d5aad413ea1d123"
 
   head "https://github.com/lounge-rocks/crab_share.git", branch: "main"
 
@@ -29,5 +29,15 @@ def install
     # check if help text is printed
     output = shell_output("#{bin}/crab_share --help")
     assert_match "Usage:", output
+
+    # upload a test file - expect an error because no credentials are provided
+    (testpath/"test.txt").write("Hello World!")
+    output = shell_output("#{bin}/crab_share test.txt 2>&1", 1)
+    assert_match "Could not read ~/.aws/crab_share.json", output
+    assert_match "No such file or directory (os error 2)", output
+
+    # upload a test file that does not exist - expect an error
+    output = shell_output("#{bin}/crab_share file-does-not-exist.txt 2>&1", 1)
+    assert_match "Path file-does-not-exist.txt does not exist", output
   end
 end