tests: handle file leaks and SVN test prompt.

- Ignore files that are generated by `brew tests`
- Make the SVN tests work without prompting for GitHub's SSL certificate

.gitignore

@@ -18,6 +18,8 @@
 /Library/Homebrew/test/bin
 /Library/Homebrew/test/coverage
 /Library/Homebrew/test/fs_leak_log
+/Library/Homebrew/test/.gem
+/Library/Homebrew/test/.subversion
 /Library/Homebrew/tmp
 /Library/Homebrew/.npmignore
 /Library/LinkedKegs

Library/Homebrew/test/utils/svn_spec.rb

@@ -32,7 +32,9 @@ describe Utils do
 
       it "returns true when remote exists", :needs_network, :needs_svn do
         HOMEBREW_CACHE.cd do
-          system HOMEBREW_SHIMS_PATH/"scm/svn", "checkout", "https://github.com/Homebrew/install"
+          system HOMEBREW_SHIMS_PATH/"scm/svn", "checkout",
+            "--non-interactive", "--trust-server-cert", "--quiet",
+            "https://github.com/Homebrew/install"
         end
 
         expect(described_class).to be_svn_remote_exists(HOMEBREW_CACHE/"install")

Library/Homebrew/utils/svn.rb

@@ -10,6 +10,7 @@ module Utils
 
   def self.svn_remote_exists?(url)
     return true unless svn_available?
-    quiet_system "svn", "ls", url, "--depth", "empty"
+    ssl_args = ["--non-interactive", "--trust-server-cert"] if ENV["HOMEBREW_TEST_ONLINE"]
+    quiet_system "svn", "ls", url, "--depth", "empty", *ssl_args
   end
 end