do testing in sandbox repo.

test/git-open.bats

@@ -3,22 +3,38 @@
 load 'test_helper/bats-support/load'
 load 'test_helper/bats-assert/load'
 
+foldername="sandboxrepo"
+
 setup() {
-  git checkout --force master
+  create_git_sandbox
 }
 
 @test "git-open gh basic" {
-  run git-open
-  assert_output 'https://github.com/paulirish/git-open/'
+  run ../git-open
+  git remote set-url origin git@github.com:user/repo.git
+  assert_output 'https://github.com/user/repo/'
 }
 
 @test "git-open gh branch" {
   git checkout --force -b mybranch
-  run git-open
-  assert_output 'https://github.com/paulirish/git-open/tree/mybranch'
+  run ../git-open
+  assert_output 'https://github.com/user/repo/tree/mybranch'
 }
 
 teardown() {
-  git branch -D mybranch
-  git checkout --force master
+  cd ..
+  rm -rf "$foldername"
 }
+
+# helper to create a test git sandbox that won't dirty the real repo
+function create_git_sandbox() {
+  rm -rf "$foldername"
+  mkdir "$foldername"
+  cd "$foldername"
+  git init -q
+  git remote add origin git@github.com:user/repo.git
+  git checkout -fb master
+  echo "ok" > readme.txt
+  git add readme.txt
+  git commit -m "add file" -q
+}