Recognize + in sematnic tags

tests/SlackBuilder/InfoSpec.hs

@@ -1,3 +1,7 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
 module SlackBuilder.InfoSpec
     ( spec
     ) where

tests/SlackBuilder/LatestVersionCheckSpec.hs

@@ -0,0 +1,24 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
+module SlackBuilder.LatestVersionCheckSpec
+    ( spec
+    ) where
+
+import SlackBuilder.LatestVersionCheck
+import Test.Hspec (Spec, describe, it, shouldBe)
+
+spec :: Spec
+spec = do
+    describe "stableTagTransform" $ do
+        it "excludes tags with +" $
+            let given = "v2.6.0+unreleased"
+                actual = stableTagTransform given
+             in actual `shouldBe` Nothing
+
+        it "recognizes a stable version" $
+            let given = "v2.6.0"
+                actual = stableTagTransform given
+                expected = Just "2.6.0"
+             in actual `shouldBe` expected

tests/SlackBuilder/PackageSpec.hs

@@ -1,3 +1,7 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
 module SlackBuilder.PackageSpec
     ( spec
     ) where