From 10ff69c7b9c82b08fc5948a0f3090cce3130bd8f Mon Sep 17 00:00:00 2001
From: Matt Parsons <parsonsmatt@gmail.com>
Date: Mon, 6 May 2019 19:35:27 -0600
Subject: [PATCH] mkEntityDefList (#904)

* Fix version bound; revision on Hackage

* mkEntityDefList

* Remove errant comment line [ci skip]

* Switch to formatting

* remove 8.4.1 ci [ci skip]

* remove nightly thing [ci skip]
---
 .travis.yml                                   |  4 ---
 persistent-template/ChangeLog.md              |  4 +++
 persistent-template/Database/Persist/TH.hs    | 31 +++++++++++++++++++
 persistent-template/persistent-template.cabal |  2 +-
 4 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 84ac0d87f..ae183e21a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,9 +17,6 @@ matrix:
   - env: BUILD=cabal GHCVER=8.2.2 CABALVER=2.0 HAPPYVER=1.19.5 ALEXVER=3.1.7
     compiler: ": #GHC 8.2.2"
     addons: {postgresql: "9.6", apt: {packages: [cabal-install-2.0,ghc-8.2.2,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
-  - env: BUILD=cabal GHCVER=8.4.1 CABALVER=2.0 HAPPYVER=1.19.5 ALEXVER=3.1.7
-    compiler: ": #GHC 8.4.1"
-    addons: {postgresql: "9.6", apt: {packages: [cabal-install-2.0,ghc-8.4.1,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
   - env: BUILD=cabal GHCVER=8.4.4 CABALVER=2.0 HAPPYVER=1.19.5 ALEXVER=3.1.7
     compiler: ": #GHC 8.4.4"
     addons: {postgresql: "9.6", apt: {packages: [cabal-install-2.0,ghc-8.4.4,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
@@ -40,7 +37,6 @@ matrix:
   # Nightly builds are allowed to fail
   - env: BUILD=stack ARGS="--resolver nightly"
     compiler: ": #stack nightly"
-    addons: {apt: {packages: [libgmp-dev]}}
 
   allow_failures:
   - env: BUILD=cabal GHCVER=head  CABALVER=head HAPPYVER=1.19.5 ALEXVER=3.1.7
diff --git a/persistent-template/ChangeLog.md b/persistent-template/ChangeLog.md
index 1e0787a4b..f5aa7f414 100644
--- a/persistent-template/ChangeLog.md
+++ b/persistent-template/ChangeLog.md
@@ -1,3 +1,7 @@
+## 2.7.1
+
+* Add the `mkEntityDefList` function to work around [#902](https://github.com/yesodweb/persistent/issues/902). [#904](https://github.com/yesodweb/persistent/pull/904)
+
 ## 2.7.0
 
 * Depends on `persistent-2.10.0` which provides the `OnlyOneUniqueKey` and `AtLeastOneUniqueKey` classes. Automatically generates instances for these classes based on how many unique keys the entity definition gets. This changes requires `UndecidableInstances` to be enabled on each module that generates entity definitions. [#885](https://github.com/yesodweb/persistent/pull/885)
diff --git a/persistent-template/Database/Persist/TH.hs b/persistent-template/Database/Persist/TH.hs
index 5df4c7c31..66a7b2430 100644
--- a/persistent-template/Database/Persist/TH.hs
+++ b/persistent-template/Database/Persist/TH.hs
@@ -32,6 +32,7 @@ module Database.Persist.TH
     , mkMigrate
     , mkSave
     , mkDeleteCascade
+    , mkEntityDefList
     , share
     , derivePersistField
     , derivePersistFieldJSON
@@ -1361,6 +1362,36 @@ mkDeleteCascade mps defs = do
                 [normalClause [VarP key] (DoE stmts)]
             ]
 
+-- | Creates a declaration for the @['EntityDef']@ from the @persistent@
+-- schema. This is necessary because the Persistent QuasiQuoter is unable
+-- to know the correct type of ID fields, and assumes that they are all
+-- Int64.
+--
+-- Provide this in the list you give to 'share', much like @'mkMigrate'@.
+--
+-- @
+-- 'share' ['mkMigrate' "migrateAll", 'mkEntityDefList' "entityDefs"] [...]
+-- @
+--
+-- @since 2.7.1
+mkEntityDefList
+    :: String
+    -- ^ The name that will be given to the 'EntityDef' list.
+    -> [EntityDef]
+    -> Q [Dec]
+mkEntityDefList entityList entityDefs = do
+    let entityListName = mkName entityList
+    edefs <- fmap ListE
+        . forM entityDefs
+        $ \(EntityDef { entityHaskell = HaskellName haskellName }) ->
+            let entityType = conT (mkName (T.unpack haskellName))
+             in [|entityDef (Proxy :: Proxy $(entityType))|]
+    typ <- [t|[EntityDef]|]
+    pure
+        [ SigD entityListName typ
+        , ValD (VarP entityListName) (NormalB edefs) []
+        ]
+
 mkUniqueKeys :: EntityDef -> Q Dec
 mkUniqueKeys def | entitySum def =
     return $ FunD 'persistUniqueKeys [normalClause [WildP] (ListE [])]
diff --git a/persistent-template/persistent-template.cabal b/persistent-template/persistent-template.cabal
index 462915e62..c1f7734aa 100644
--- a/persistent-template/persistent-template.cabal
+++ b/persistent-template/persistent-template.cabal
@@ -1,5 +1,5 @@
 name:            persistent-template
-version:         2.7.0
+version:         2.7.1
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>