From 34207f872f200a58c4a9dc3da864bf45df8d3b72 Mon Sep 17 00:00:00 2001
From: Micah Jerome Ellison <micah.jerome.ellison@gmail.com>
Date: Sat, 4 Jul 2020 15:09:05 -0700
Subject: [PATCH] Add Python version check and faulty test to confirm it's
 working (should fail on 3.6 build only)

---
 features/core.feature  |  4 ++++
 features/steps/core.py | 11 +++++++++++
 jrnl/cli.py            |  4 ++++
 3 files changed, 19 insertions(+)

diff --git a/features/core.feature b/features/core.feature
index 5bec4e95..99bcf5a5 100644
--- a/features/core.feature
+++ b/features/core.feature
@@ -135,3 +135,7 @@ Feature: Basic reading and writing to a journal
         When we run "jrnl --diagnostic"
         Then the output should contain "jrnl"
         And the output should contain "Python"
+
+    Scenario: Version warning appears for versions below 3.7
+        When we run "jrnl --diagnostic"
+        Then the Python version warning should appear if our version is below "3.7"
diff --git a/features/steps/core.py b/features/steps/core.py
index 13b11bd2..14c5268a 100644
--- a/features/steps/core.py
+++ b/features/steps/core.py
@@ -371,6 +371,17 @@ def list_journal_directory(context, journal="default"):
         for file in f:
             print(os.path.join(root, file))
 
+@then("the Python version warning should appear if our version is below {version}")
+def check_python_warning_if_version_low_enough(context, version):
+    import packaging.version
+    import platform
+
+    if packaging.version.parse(platform.python_version()) < packaging.version.parse(version):
+        out = context.stderr_capture.getvalue()
+        assert "THIS SHOULD FAIL ON 3.6 REMOVE WHEN CONFIRMING - WARNING: Python versions" in out
+    else:
+        assert True
+
 
 @then("fail")
 def debug_fail(context):
diff --git a/jrnl/cli.py b/jrnl/cli.py
index 8e583391..e97130ac 100644
--- a/jrnl/cli.py
+++ b/jrnl/cli.py
@@ -21,6 +21,7 @@
 
 import argparse
 import logging
+import packaging.version
 import platform
 import re
 import sys
@@ -313,6 +314,9 @@ def configure_logger(debug=False):
 
 
 def run(manual_args=None):
+    if packaging.version.parse(platform.python_version()) < packaging.version.parse('3.7'):
+        print("WARNING: Python versions below 3.7 are not supported by jrnl\n", file=sys.stderr)
+
     if manual_args is None:
         manual_args = sys.argv[1:]