test: add MDEBUG environment variable

When the OpenSSL is compiled with crypto-mdebug, and the environment
variable MDEBUG is set, print found memory leaks on exit.

2 files changed, 24 insertions, 1 deletions

diff --git a/test/test_engine.rb b/test/test_engine.rb
index c236bd69..529a8010 100644
--- a/test/test_engine.rb
+++ b/test/test_engine.rb
@@ -83,7 +83,7 @@ class OpenSSL::TestEngine < OpenSSL::TestCase
 
   # this is required because OpenSSL::Engine methods change global state
   def with_openssl(code)
-    assert_separately(["-ropenssl"], <<~"end;")
+    assert_separately([{ "MDEBUG" => nil }, "-ropenssl"], <<~"end;")
       require #{__FILE__.dump}
       include OpenSSL::TestEngine::Utils
       #{code}
diff --git a/test/utils.rb b/test/utils.rb
index 5cd772e7..fc303d1d 100644
--- a/test/utils.rb
+++ b/test/utils.rb
@@ -8,6 +8,29 @@ begin
   OpenSSL.fips_mode=false
 rescue LoadError
 end
+
+# Compile OpenSSL with crypto-mdebug and run this test suite with MDEBUG
+# environment variable to enable memory leak check.
+if ENV["MDEBUG"]
+  begin
+    require "mdebug"
+  rescue LoadError
+  end
+
+  if OpenSSL.respond_to?(:print_mem_leaks)
+    END {
+      # FIXME: maybe extract fixtures to file and load dynamically?
+      OpenSSL::TestUtils.constants.each do |v|
+        OpenSSL::TestUtils.send(:remove_const, v)
+      end
+      GC.start
+      OpenSSL.print_mem_leaks
+    }
+  else
+    warn "OpenSSL is not built with crypto-mdebug"
+  end
+end
+
 require "test/unit"
 require "digest/md5"
 require 'tempfile'