1 files changed, 43 insertions, 0 deletions
diff --git a/scripts/lib/glfm/shared.rb b/scripts/lib/glfm/shared.rb
new file mode 100644
index 00000000000..f11c66eb8be
--- /dev/null
+++ b/scripts/lib/glfm/shared.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+require 'fileutils'
+require 'open3'
+
+module Glfm
+  module Shared
+    def write_file(file_path, file_content_string)
+      FileUtils.mkdir_p(File.dirname(file_path))
+      # NOTE: We don't use the block form of File.open because we want to be able to easily
+      # mock it for testing.
+      io = File.open(file_path, 'w')
+      io.binmode
+      io.write(file_content_string)
+      # NOTE: We are using #fsync + #close_write instead of just #close`, in order to unit test
+      # with a real StringIO and not just a mock object.
+      io.fsync
+      io.close_write
+    end
+
+    # All script output goes through this method. This makes it easy to mock in order to prevent
+    # output from being printed to the console during tests. We don't want to directly mock
+    # Kernel#puts, because that could interfere or cause spurious test failures when #puts is used
+    # for debugging. And for some reason RuboCop says `rubocop:disable Rails/Output` would be
+    # redundant here, so not including it.
+    def output(string)
+      puts string
+    end
+
+    def run_external_cmd(cmd)
+      # noinspection RubyMismatchedArgumentType
+      rails_root = File.expand_path('../../../', __dir__)
+
+      # See https://stackoverflow.com/a/20001569/25192
+      stdout_and_stderr_str, status = Open3.capture2e(cmd, chdir: rails_root)
+
+      return stdout_and_stderr_str if status.success?
+
+      warn("Error running command `#{cmd}`\n")
+      warn(stdout_and_stderr_str)
+      raise
+    end
+  end
+end