From 8c82ee4e0484df4370200e13bd8b07a069b3191a Mon Sep 17 00:00:00 2001
From: Joao Fernandes <joao@hopin.to>
Date: Fri, 24 Sep 2021 16:10:54 +0100
Subject: [PATCH 1/3] Add Gemfile.lock to .gitgnore

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 9106b2a..4ea5798 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,4 @@
 /pkg/
 /spec/reports/
 /tmp/
+Gemfile.lock

From 37192dc98835edaf31fc1ac05dc1cd2d1419b7b2 Mon Sep 17 00:00:00 2001
From: Joao Fernandes <joao@hopin.to>
Date: Fri, 24 Sep 2021 16:11:11 +0100
Subject: [PATCH 2/3] Out with minitest, in with test-unit

Maybe some long time ago this used minitest? That's not the case anymore.
---
 Gemfile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Gemfile b/Gemfile
index 8ba2339..eb86192 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
 source "https://rubygems.org"
 
 gem "rake"
-gem "minitest"
+gem "test-unit"

From 6401ef58243efa65e0dbbfcddf9610a084b84886 Mon Sep 17 00:00:00 2001
From: Joao Fernandes <joao@hopin.to>
Date: Fri, 24 Sep 2021 16:13:40 +0100
Subject: [PATCH 3/3] Avoid unnecessary string duplication

String#ljust returns a new string, so whenever we need to add
padding, we can replace "-/" in place with String#tr! and avoid creating
yet another copy of the string.
---
 lib/base64.rb | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/base64.rb b/lib/base64.rb
index de1e8c0..693aa1f 100644
--- a/lib/base64.rb
+++ b/lib/base64.rb
@@ -99,9 +99,11 @@ def urlsafe_decode64(str)
     # NOTE: RFC 4648 does say nothing about unpadded input, but says that
     # "the excess pad characters MAY also be ignored", so it is inferred that
     # unpadded input is also acceptable.
-    str = str.tr("-_", "+/")
     if !str.end_with?("=") && str.length % 4 != 0
       str = str.ljust((str.length + 3) & ~3, "=")
+      str.tr!("-_", "+/")
+    else
+      str = str.tr("-_", "+/")
     end
     strict_decode64(str)
   end