[rubygems/rubygems] Vendor a pure ruby implementation of SHA1

This allows `Source::Git` to no longer load the `digest` gem as it is causing
issues on Ruby 3.1.

https://github.com/rubygems/rubygems/pull/4989/commits/c19a9f2ff7

1 files changed, 17 insertions, 0 deletions

diff --git a/spec/bundler/bundler/digest_spec.rb b/spec/bundler/bundler/digest_spec.rb
new file mode 100644
index 0000000000..d6bb043fd0
--- /dev/null
+++ b/spec/bundler/bundler/digest_spec.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require "digest"
+require "bundler/digest"
+
+RSpec.describe Bundler::Digest do
+  context "SHA1" do
+    subject { Bundler::Digest }
+    let(:stdlib) { ::Digest::SHA1 }
+
+    it "is compatible with stdlib" do
+      ["foo", "skfjsdlkfjsdf", "3924m", "ldskfj"].each do |payload|
+        expect(subject.sha1(payload)).to be == stdlib.hexdigest(payload)
+      end
+    end
+  end
+end