diff --git a/test/init.bats b/test/init.bats
new file mode 100644
index 0000000..6edcc47
--- /dev/null
+++ b/test/init.bats
@@ -0,0 +1,44 @@
+#!/usr/bin/env bats
+
+load test_helper
+
+@test "detect parent shell" {
+  root="$(cd $BATS_TEST_DIRNAME/.. && pwd)"
+  SHELL=/bin/false run pyenv-virtualenv-init -
+  assert_success
+  assert_output_contains '  PROMPT_COMMAND="_pyenv_virtualenv_hook;$PROMPT_COMMAND";'
+}
+
+@test "sh-compatible instructions" {
+  run pyenv-virtualenv-init bash
+  assert [ "$status" -eq 1 ]
+  assert_output_contains 'eval "$(pyenv virtualenv-init -)"'
+
+  run pyenv-virtualenv-init zsh
+  assert [ "$status" -eq 1 ]
+  assert_output_contains 'eval "$(pyenv virtualenv-init -)"'
+}
+
+@test "fish instructions" {
+  run pyenv-virtualenv-init fish
+  assert [ "$status" -eq 1 ]
+  assert_output_contains 'status --is-interactive; and . (pyenv virtualenv-init -|psub)'
+}
+
+@test "outputs bash-specific syntax" {
+  run pyenv-virtualenv-init - bash
+  assert_success
+  assert_output_contains '  PROMPT_COMMAND="_pyenv_virtualenv_hook;$PROMPT_COMMAND";'
+}
+
+@test "outputs fish-specific syntax" {
+  run pyenv-virtualenv-init - fish
+  assert_success
+  assert_output_contains 'function _pyenv_virtualenv_hook --on-event fish_prompt;'
+}
+
+@test "outputs zsh-specific syntax" {
+  run pyenv-virtualenv-init - zsh
+  assert_success
+  assert_output_contains '  precmd_functions+=_pyenv_virtualenv_hook;'
+}