From 9ed66591c3b8c46c90657490f53effa22e505f3a Mon Sep 17 00:00:00 2001
From: Reed Allman <reed.allman@oracle.com>
Date: Wed, 7 Jun 2017 15:48:00 -0700
Subject: [PATCH] need to use >=17.05 (not 17.5), add trimming for weird builds

---
 fn/common.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fn/common.go b/fn/common.go
index ee2dff95b..a7ccfe154 100644
--- a/fn/common.go
+++ b/fn/common.go
@@ -10,6 +10,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"strings"
+	"unicode"
 
 	"github.com/coreos/go-semver/semver"
 
@@ -130,7 +131,10 @@ func dockerVersionCheck() error {
 	if err != nil {
 		return fmt.Errorf("could not check Docker version: %v", err)
 	}
-	v, err := semver.NewVersion(string(out))
+	// dev / test builds append '-ce', trim this
+	trimmed := strings.TrimRightFunc(string(out), func(r rune) bool { return r != '.' && !unicode.IsDigit(r) })
+
+	v, err := semver.NewVersion(trimmed)
 	if err != nil {
 		return fmt.Errorf("could not check Docker version: %v", err)
 	}