refactor(users/glittershark): Rename to grfn

Rename my //users directory and all places that refer to glittershark to
grfn, including nix references and documentation.

This may require some extra attention inside of gerrit's database after
it lands to allow me to actually push things.

Change-Id: I4728b7ec2c60024392c1c1fa6e0d4a59b3e266fa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2933
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
Reviewed-by: lukegb <lukegb@tvl.fyi>
Reviewed-by: glittershark <grfn@gws.fyi>

users/grfn/xanthous/test/Xanthous/Messages/TemplateSpec.hs

@@ -0,0 +1,80 @@
+--------------------------------------------------------------------------------
+module Xanthous.Messages.TemplateSpec (main, test) where
+--------------------------------------------------------------------------------
+import Test.Prelude
+import Test.QuickCheck.Instances.Text ()
+import Data.List.NonEmpty (NonEmpty(..))
+import Data.Function (fix)
+--------------------------------------------------------------------------------
+import Xanthous.Messages.Template
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = defaultMain test
+
+test :: TestTree
+test = testGroup "Xanthous.Messages.Template"
+  [ testGroup "parsing"
+    [ testProperty "literals" $ forAll genLiteral $ \s ->
+        testParse template s === Right (Literal s)
+    , parseCase "escaped curlies"
+      "foo\\{"
+      $ Literal "foo{"
+    , parseCase "simple substitution"
+      "foo {{bar}}"
+      $ Literal "foo " `Concat` Subst (SubstPath $ "bar" :| [])
+    , parseCase "substitution with filters"
+      "foo {{bar | baz}}"
+      $ Literal "foo "
+      `Concat` Subst (SubstFilter (SubstPath $ "bar" :| [])
+                                  (FilterName "baz"))
+    , parseCase "substitution with multiple filters"
+      "foo {{bar | baz | qux}}"
+      $ Literal "foo "
+      `Concat` Subst (SubstFilter (SubstFilter (SubstPath $ "bar" :| [])
+                                                (FilterName "baz"))
+                                  (FilterName "qux"))
+    , parseCase "two substitutions and a literal"
+      "{{a}}{{b}}c"
+      $ Subst (SubstPath $ "a" :| [])
+      `Concat` Subst (SubstPath $ "b" :| [])
+      `Concat` Literal "c"
+    , localOption (QuickCheckTests 10)
+    $ testProperty "round-trips with ppTemplate" $ \tpl ->
+        testParse template (ppTemplate tpl) === Right tpl
+    ]
+  , testBatch $ monoid @Template mempty
+  , testGroup "rendering"
+    [ testProperty "rendering literals renders literally"
+      $ forAll genLiteral $ \s fs vs ->
+        render fs vs (Literal s) === Right s
+    , testProperty "rendering substitutions renders substitutions"
+      $ forAll genPath $ \ident val fs ->
+        let tpl = Subst (SubstPath ident)
+            tvs = varsWith ident val
+        in render fs tvs tpl === Right val
+    , testProperty "filters filter" $ forAll genPath
+      $ \ident filterName filterFn val ->
+        let tpl = Subst (SubstFilter (SubstPath ident) filterName)
+            fs = mapFromList [(filterName, filterFn)]
+            vs = varsWith ident val
+        in render fs vs tpl === Right (filterFn val)
+    ]
+  ]
+  where
+    genLiteral = pack . filter (`notElem` ['\\', '{']) <$> arbitrary
+    parseCase name input expected =
+      testCase name $ testParse template input @?= Right expected
+    testParse p = over _Left errorBundlePretty . runParser p "<test>"
+    genIdentifier = pack @Text <$> listOf1 (elements identifierChars)
+    identifierChars = ['a'..'z'] <> ['A'..'Z'] <> ['-', '_']
+
+    varsWith (p :| []) val = vars [(p, Val val)]
+    varsWith (phead :| ps) val = vars . pure . (phead ,) . flip fix ps $
+      \next pth -> case pth of
+          [] -> Val val
+          p : ps' -> nested [(p, next ps')]
+
+    genPath = (:|) <$> genIdentifier <*> listOf genIdentifier
+
+--