fix: Throw SFTP::Error when Bash process started by Shell fails

lib/sftp/shell.rb

@@ -2,7 +2,11 @@ module SFTP
   module Shell
     def self.run(array_of_commands)
       command_str = [array_of_commands].join(" ")
-      `bash  -c \"#{command_str}\"`
+      output = `bash  -c \"#{command_str}\"`
+      unless $CHILD_STATUS.success?
+        raise Error, "Error occurred during SFTP process: #{$CHILD_STATUS.exitstatus}"
+      end
+      output
     end
   end
 end

spec/sftp_spec.rb

@@ -95,3 +95,19 @@
     end
   end
 end
+
+RSpec.describe SFTP::Shell do
+  before(:each) do
+    @shell = SFTP::Shell
+  end
+
+  context "#run" do
+    it "throws Error when run fails" do
+      expect { @shell.run ["gobbledegook"] }.to raise_error(SFTP::Error)
+    end
+
+    it "returns the output from the command" do
+      expect(@shell.run(["ls"]).class.to_s).to eq("String")
+    end
+  end
+end