Allow for more complex version comparison (redux) (#797)

* Allow for more complex version comparison

Allow for letters in version names
Add tests for version info

* Fix integration tests

* Combine code from @mturzanska's PR with development

Based on: #577
Fixes: #557

dbt/version.py

@@ -1,7 +1,7 @@
-import argparse
-import os
 import re
 
+import dbt.semver
+
 try:
     # For Python 3.0 and later
     from urllib.request import urlopen
@@ -14,59 +14,59 @@
     'master/.bumpversion.cfg'
 
 
-def __parse_version(contents):
-    matches = re.search(r"current_version = ([\.0-9]+)", contents)
+def get_version_string_from_text(contents):
+    matches = re.search(r"current_version = ([\.0-9a-z]+)", contents)
     if matches is None or len(matches.groups()) != 1:
-        return "unknown"
-    else:
-        version = matches.groups()[0]
-        return version
-
+        return ""
+    version = matches.groups()[0]
+    return version
 
-def get_version():
-    return __version__
 
-
-def get_latest_version():
+def get_remote_version_file_contents(url=REMOTE_VERSION_FILE):
     try:
-        f = urlopen(REMOTE_VERSION_FILE)
+        f = urlopen(url)
         contents = f.read()
     except Exception:
         contents = ''
     if hasattr(contents, 'decode'):
         contents = contents.decode('utf-8')
-    return __parse_version(contents)
+    return contents
 
 
-def not_latest():
-    return """Your version of dbt is out of date! You can find instructions
-    for upgrading here:
-
-    https://docs.getdbt.com/docs/installation
-    """
+def get_latest_version():
+    contents = get_remote_version_file_contents()
+    version_string = get_version_string_from_text(contents)
+    return dbt.semver.VersionSpecifier.from_version_string(version_string)
 
 
-def get_version_string():
-    return "installed version: {}\n   latest version: {}".format(
-        installed, latest
-    )
+def get_installed_version():
+    return dbt.semver.VersionSpecifier.from_version_string(__version__)
 
 
 def get_version_information():
-    basic = get_version_string()
+    installed = get_installed_version()
+    latest = get_latest_version()
 
-    if is_latest():
-        basic += '\nUp to date!'
-    else:
-        basic += '\n{}'.format(not_latest())
+    installed_s = installed.to_version_string(skip_matcher=True)
+    latest_s = latest.to_version_string(skip_matcher=True)
 
-    return basic
+    version_msg = ("installed version: {}\n"
+                   "   latest version: {}\n\n".format(installed_s, latest_s))
 
+    if installed == latest:
+        return "{}Up to date!".format(version_msg)
 
-def is_latest():
-    return installed == latest
+    elif installed > latest:
+        return ("{}Your version of dbt is ahead of the latest "
+                "release!".format(version_msg))
+
+    else:
+        return ("{}Your version of dbt is out of date! "
+                "You can find instructions for upgrading here:\n"
+                "https://docs.getdbt.com/docs/installation"
+                .format(version_msg))
 
 
 __version__ = '0.10.1'
-installed = get_version()
+installed = get_installed_version()
 latest = get_latest_version()

test/unit/test_version.py

@@ -0,0 +1,89 @@
+from mock import patch, MagicMock
+import unittest
+
+import dbt.version
+
+
+class VersionTest(unittest.TestCase):
+
+    @patch("dbt.version.__version__", "0.10.0")
+    def test_versions_equal(self):
+
+        dbt.version.get_remote_version_file_contents = MagicMock(
+            return_value="""
+                [bumpversion]
+                current_version = 0.10.0
+                commit = True
+                tag = True
+
+                [bumpversion:file:setup.py]
+
+                [bumpversion:file:dbt/version.py]
+            """)
+
+        latest_version = dbt.version.get_latest_version()
+        installed_version = dbt.version.get_installed_version()
+        version_information = dbt.version.get_version_information()
+
+        expected_version_information = "installed version: 0.10.0\n" \
+            "   latest version: 0.10.0\n\n" \
+            "Up to date!"
+
+        self.assertEqual(latest_version, installed_version)
+        self.assertEqual(latest_version, installed_version)
+        self.assertMultiLineEqual(version_information,
+                                  expected_version_information)
+
+    @patch("dbt.version.__version__", "0.10.2-a1")
+    def test_installed_version_greater(self):
+        dbt.version.get_remote_version_file_contents = MagicMock(
+            return_value="""
+                [bumpversion]
+                current_version = 0.10.1
+                commit = True
+                tag = True
+
+                [bumpversion:file:setup.py]
+
+                [bumpversion:file:dbt/version.py]
+            """)
+
+        latest_version = dbt.version.get_latest_version()
+        installed_version = dbt.version.get_installed_version()
+        version_information = dbt.version.get_version_information()
+
+        expected_version_information = "installed version: 0.10.2-a1\n" \
+            "   latest version: 0.10.1\n\n" \
+            "Your version of dbt is ahead of the latest release!"
+
+        assert installed_version > latest_version
+        self.assertMultiLineEqual(version_information,
+                                  expected_version_information)
+
+    @patch("dbt.version.__version__", "0.9.5")
+    def test_installed_version_lower(self):
+        dbt.version.get_remote_version_file_contents = MagicMock(
+            return_value="""
+                [bumpversion]
+                current_version = 0.10.0
+                commit = True
+                tag = True
+
+                [bumpversion:file:setup.py]
+
+                [bumpversion:file:dbt/version.py]
+            """)
+
+        latest_version = dbt.version.get_latest_version()
+        installed_version = dbt.version.get_installed_version()
+        version_information = dbt.version.get_version_information()
+
+        expected_version_information = "installed version: 0.9.5\n" \
+            "   latest version: 0.10.0\n\n" \
+            "Your version of dbt is out of date! " \
+            "You can find instructions for upgrading here:\n" \
+            "https://docs.getdbt.com/docs/installation"
+
+        assert installed_version < latest_version
+        self.assertMultiLineEqual(version_information,
+                                  expected_version_information)