From 3e678b322a625d5a45352da233850e730630ceb6 Mon Sep 17 00:00:00 2001
From: Sam O'Connor <sam@octech.com.au>
Date: Mon, 20 Jun 2016 10:27:34 +1000
Subject: [PATCH] add ENV["HAVE_INFOZIP"] option to support userimg.jl build

---
 src/InfoZIP.jl | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/InfoZIP.jl b/src/InfoZIP.jl
index c588e7b..7cb8c59 100644
--- a/src/InfoZIP.jl
+++ b/src/InfoZIP.jl
@@ -13,18 +13,20 @@ Base.read(cmd::Cmd) = readbytes(cmd)
 end
 
 
-have_infozip = false
-try
-    if ismatch(r"^UnZip.*by Info-ZIP.", readstring(`unzip`))
-        have_infozip = true
+have_infozip() = haskey(ENV, "HAVE_INFOZIP") || try
+    ismatch(r"^UnZip.*by Info-ZIP.", readstring(`unzip`))
+catch ex
+    if isa(ex, Base.UVError) && ex.code == Base.UV_ENOENT
+        return false
     end
-catch
+    rethrow(ex)
 end
 
 
-if have_infozip
+if have_infozip()
     include("info_zip.jl")
 else
+    warn("InfoZIP falling back to ZipFile.jl backend!")
     include("zip_file.jl")
 end