Fail when run against Python juju environment

environs/jujutest/livetests.go

Index: environs/jujutest/livetests.go
=== modified file 'environs/jujutest/livetests.go'
--- environs/jujutest/livetests.go	2013-06-26 13:19:16 +0000
+++ environs/jujutest/livetests.go	2013-06-29 02:49:49 +0000
@@ -23,6 +23,7 @@
 	coretesting "launchpad.net/juju-core/testing"
 	"launchpad.net/juju-core/utils"
 	"launchpad.net/juju-core/version"
+	"strings"
 	"time"
 )
 
@@ -471,6 +472,67 @@
 		"juju-core storage writing verified: ok\n")
 }
 
+func restoreBootstrapVerificationFile(c *C, storage environs.Storage) {
+	content := "juju-core storage writing verified: ok\n"
+	contentReader := strings.NewReader(content)
+	err := storage.Put("bootstrap-verify", contentReader,
+		int64(len(content)))
+	c.Assert(err, IsNil)
+}
+
+func (t *LiveTests) TestCheckEnvironmentOnConnect(c *C) {
+	// When new connection is established to a bootstraped environment,
+	// it is checked that we are running against a juju-core environment.
+	t.BootstrapOnce(c)
+
+	conn, err := juju.NewConn(t.Env)
+	c.Assert(err, IsNil)
+	conn.Close()
+}
+
+func (t *LiveTests) TestCheckEnvironmentOnConnectNoVerificationFile(c *C) {
+	// When new connection is established to a bootstraped environment,
+	// it is checked that we are running against a juju-core environment.
+	//
+	// Absence of a verification file means it is a juju-core environment
+	// with an older version, which is fine.
+	t.BootstrapOnce(c)
+	environ := t.Env
+	storage := environ.Storage()
+	err := storage.Remove("bootstrap-verify")
+	c.Assert(err, IsNil)
+	defer restoreBootstrapVerificationFile(c, storage)
+
+	conn, err := juju.NewConn(t.Env)
+	c.Assert(err, IsNil)
+	conn.Close()
+}
+
+func (t *LiveTests) TestCheckEnvironmentOnConnectBadVerificationFile(c *C) {
+	// When new connection is established to a bootstraped environment,
+	// it is checked that we are running against a juju-core environment.
+	//
+	// If the verification file has unexpected content, it is not
+	// a juju-core environment (likely to a Python juju environment).
+	t.BootstrapOnce(c)
+	environ := t.Env
+	storage := environ.Storage()
+
+	// Finally, replace the content with an arbitrary string.
+	badVerificationContent := "bootstrap storage verification"
+	reader := strings.NewReader(badVerificationContent)
+	err := storage.Put(
+		"bootstrap-verify",
+		reader,
+		int64(len(badVerificationContent)))
+	c.Assert(err, IsNil)
+	defer restoreBootstrapVerificationFile(c, storage)
+
+	// Running NewConn() should fail.
+	_, err = juju.NewConn(t.Env)
+	c.Assert(err, Equals, environs.InvalidEnvironmentError)
+}
+
 type tooler interface {
 	Life() state.Life
 	AgentTools() (*state.Tools, error)