more tests

test/fixtures/pipenv-version/Pipfile

+[[source]]
+url = "https://pypi.python.org/simple"
+verify_ssl = true
+
+[packages]
+requests = "*"
+
+[requires]
+python_version = "3.6"
\ No newline at end of file

test/fixtures/pipenv/Pipfile

+[packages]
+requests = "*"

test/run

@@ -5,6 +5,18 @@ testNoRequirements() {
   assertCapturedError
 }
 
+testPipenv() {
+  compile "pipenv"
+  assertCaptured "requests"
+  assertCapturedSuccess
+}
+
+testPipenvVersion() {
+  compile "pipenv-version"
+  assertCaptured "3.6"
+  assertCapturedSuccess
+}
+
 
 testSetupPy() {
   compile "setup-py"