From cf2948df0c2b7175c1dc91c8fd1a5bacb65b2c01 Mon Sep 17 00:00:00 2001
From: Erchiusx <99174225+Erchiusx@users.noreply.github.com>
Date: Wed, 25 Dec 2024 19:38:53 +0800
Subject: [PATCH] ghcup: support vanilla and cross compilers (#126)
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* Update ghcupsync.hs

ghcup metadata 在 0.0.7 添加了 vanilla ，
并在 0.0.8 添加了 cross compiler ，
而在原本的 version parser 中并没有支持。

我修改了 parseVersionFromFileName 以添加支持，
同时考虑到未来可能的更多不同 metadata 版本，
实现了向前兼容（但性能更差的） parser 版本。

* fix typo of version
---
 ghcup/ghcupsync.hs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/ghcup/ghcupsync.hs b/ghcup/ghcupsync.hs
index a171244..aea8d1a 100644
--- a/ghcup/ghcupsync.hs
+++ b/ghcup/ghcupsync.hs
@@ -72,9 +72,22 @@ parseVersionFromFileName :: FilePath -> Maybe Version
 parseVersionFromFileName filename = do
   let basename = takeBaseName filename
   noPrefix <- stripPrefix "ghcup-prereleases-" basename
+          <|> stripPrefix "ghcup-cross-" basename
+          <|> stripPrefix "ghcup-vanilla-" basename
           <|> stripPrefix "ghcup-" basename
   listToMaybe $ map fst . filter (\(_, rem) -> null rem) $ readP_to_S parseVersion noPrefix
 
+-- This version of parseVersionFromFileName may have more forward compatability
+-- but poorer performance
+-- parseVersionFromFileName filename = do
+--   let basename = takeBaseName filename
+--   case find isJust . map tryParse $ tails basename of
+--     (Just m) -> m -- if found, it will be a double Just, i.e. (Just (Just Version))
+--     Nothing  -> Nothing
+--   where
+--     tryParse :: String -> Maybe Version
+--     tryParse = listToMaybe . map fst . reverse . readP_to_S parseVersion
+
 ------------------------------------------------------------------------
 syncByMetadata :: FilePath -> FilePath -> IO ()
 syncByMetadata basedir mdpath = do