Additional windows path normalization in @erlang_config

Author: HoloRin

repositories/erlang_config.bzl

@@ -1,5 +1,6 @@
 load(
     "//:util.bzl",
+    "msys2_path",
     "path_join",
 )
 
@@ -143,13 +144,13 @@ def _default_erlang_dict(repository_ctx):
     if _is_windows(repository_ctx):
         if ERLANG_HOME_ENV_VAR in repository_ctx.os.environ:
             erlang_home = repository_ctx.os.environ[ERLANG_HOME_ENV_VAR]
-            erlang_home = erlang_home.replace("\\", "/")
-            erl_path = path_join(erlang_home, "bin", "erl.exe")
+            erl_path = erlang_home + "\\bin\\erl.exe"
         else:
             erl_path = repository_ctx.which("erl.exe")
             if erl_path == None:
                 erl_path = repository_ctx.path("C:/Program Files/Erlang OTP/bin/erl.exe")
             erlang_home = _erlang_home_from_erl_path(repository_ctx, erl_path)
+        erlang_home = msys2_path(erlang_home)
     elif ERLANG_HOME_ENV_VAR in repository_ctx.os.environ:
         erlang_home = repository_ctx.os.environ[ERLANG_HOME_ENV_VAR]
         erl_path = path_join(erlang_home, "bin", "erl")

util.bzl

@@ -1,6 +1,8 @@
 BEGINS_WITH_FUN = """beginswith() { case $2 in "$1"*) true;; *) false;; esac; }"""
 QUERY_ERL_VERSION = """erl -eval '{ok, Version} = file:read_file(filename:join([code:root_dir(), "releases", erlang:system_info(otp_release), "OTP_VERSION"])), io:fwrite(Version), halt().' -noshell"""
 
+_DRIVE_LETTERS = ["c", "d", "e"]
+
 def path_join(*components):
     nec = []
     for c in components:
@@ -9,7 +11,24 @@ def path_join(*components):
     return "/".join(nec)
 
 def windows_path(path):
-    return path.replace("/c/", "C:\\").replace("/", "\\")
+    for letter in _DRIVE_LETTERS:
+        prefix = "/%s/" % letter
+        if path.startswith(prefix):
+            return path.replace(
+                prefix,
+                "%s:\\" % letter.upper(),
+            ).replace("/", "\\")
+    return path.replace("/", "\\")
+
+def msys2_path(path):
+    for letter in _DRIVE_LETTERS:
+        prefix = "%s:\\" % letter.upper()
+        if path.startswith(prefix):
+            return path.replace(
+                prefix,
+                "/%s/" % letter,
+            ).replace("\\", "/")
+    return path.replace("\\", "/")
 
 def without(item, elements):
     c = list(elements)