From 8e0fda4d81aa8f3ac419a41f0599291dda9d1c44 Mon Sep 17 00:00:00 2001
From: Potato Hatsue <1793913507@qq.com>
Date: Tue, 15 Dec 2020 16:11:54 +0800
Subject: [PATCH] Add CPP

---
 .../hls-haddock-comments-plugin.cabal                  |  4 +++-
 .../include/ghc-api-version.h                          | 10 ++++++++++
 .../src/Ide/Plugin/HaddockComments.hs                  |  7 +++++++
 3 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 plugins/hls-haddock-comments-plugin/include/ghc-api-version.h

diff --git a/plugins/hls-haddock-comments-plugin/hls-haddock-comments-plugin.cabal b/plugins/hls-haddock-comments-plugin/hls-haddock-comments-plugin.cabal
index 94c97e5d5cd..317345ecef4 100644
--- a/plugins/hls-haddock-comments-plugin/hls-haddock-comments-plugin.cabal
+++ b/plugins/hls-haddock-comments-plugin/hls-haddock-comments-plugin.cabal
@@ -10,7 +10,9 @@ author:             Potato Hatsue
 maintainer:         berberman@yandex.com
 category:           Development
 build-type:         Simple
-extra-source-files: LICENSE
+extra-source-files:
+  include/ghc-api-version.h
+  LICENSE
 
 library
   exposed-modules:  Ide.Plugin.HaddockComments
diff --git a/plugins/hls-haddock-comments-plugin/include/ghc-api-version.h b/plugins/hls-haddock-comments-plugin/include/ghc-api-version.h
new file mode 100644
index 00000000000..11cabb3dc90
--- /dev/null
+++ b/plugins/hls-haddock-comments-plugin/include/ghc-api-version.h
@@ -0,0 +1,10 @@
+#ifndef GHC_API_VERSION_H
+#define GHC_API_VERSION_H
+
+#ifdef GHC_LIB
+#define MIN_GHC_API_VERSION(x,y,z) MIN_VERSION_ghc_lib(x,y,z)
+#else
+#define MIN_GHC_API_VERSION(x,y,z) MIN_VERSION_ghc(x,y,z)
+#endif
+
+#endif
diff --git a/plugins/hls-haddock-comments-plugin/src/Ide/Plugin/HaddockComments.hs b/plugins/hls-haddock-comments-plugin/src/Ide/Plugin/HaddockComments.hs
index 812d2c8c50b..dd5db92a8b8 100644
--- a/plugins/hls-haddock-comments-plugin/src/Ide/Plugin/HaddockComments.hs
+++ b/plugins/hls-haddock-comments-plugin/src/Ide/Plugin/HaddockComments.hs
@@ -1,8 +1,11 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE ViewPatterns #-}
 
+#include "ghc-api-version.h"
+
 module Ide.Plugin.HaddockComments where
 
 import Control.Monad (join)
@@ -93,7 +96,11 @@ keyFromTyVar :: Int -> LHsType GhcPs -> [AnnKey]
 keyFromTyVar dep c@(L _ (HsFunTy _ x y))
   | dep <= 1 = mkAnnKey c : (keyFromTyVar (succ dep) x <> keyFromTyVar (succ dep) y)
   | otherwise = []
+#if MIN_GHC_API_VERSION(8,10,0)
 keyFromTyVar dep (L _ (HsForAllTy _ _ _ x)) = keyFromTyVar dep x
+#else
+keyFromTyVar dep (L _ (HsForAllTy _ _ x)) = keyFromTyVar dep x 
+#endif
 keyFromTyVar dep (L _ (HsQualTy _ _ x)) = keyFromTyVar dep x
 keyFromTyVar dep (L _ (HsParTy _ x)) = keyFromTyVar (succ dep) x
 keyFromTyVar dep (L _ (HsBangTy _ _ x)) = keyFromTyVar dep x