Only output the header when there's plugin output.

diff --git a/bin/mailshears b/bin/mailshears
index 441708e674401e62dd0657ebe5e9e9184a7644d6..389c1774a52dbf96dc9936bb07515404da970ee6 100755 (executable)
--- a/bin/mailshears
+++ b/bin/mailshears
@@ -102,7 +102,12 @@ else
   dummy_runner_class = PruneDummyRunner
 end
 
-puts make_header(plugin_class.to_s())
+
+# Buffer the output so that we can avoid printing the informational
+# header when no plugins produce output.
+require 'stringio'
+output_buffer = StringIO.new()
+$stdout = output_buffer
 
 plugin_class.includers.each do |plugin_class_includer|
   plugin = plugin_class_includer.new()
@@ -117,5 +122,13 @@ plugin_class.includers.each do |plugin_class_includer|
   # appropriate runner. The Rm(Dummy)Runner have splats on their
   # *target arguments as well, to turn ARGV back into an array.
   runner.run(plugin, *ARGV)
+end
 
+# Restore stdout, and print the header plus whatever the plugins
+# produced if they produced anything. If they didn't, we avoid
+# printing the header.
+$stdout = STDOUT
+if output_buffer.size > 0 then
+  puts make_header(plugin_class.to_s())
+  puts output_buffer.string()
 end