From 7c1f48e0ad9f6a37892d83be3118cf9d15263554 Mon Sep 17 00:00:00 2001
From: Alexey Khit <alexey.khit@gmail.com>
Date: Sat, 14 Jan 2023 17:25:05 +0300
Subject: [PATCH] Support empty default environment value

---
 pkg/shell/env.go | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/pkg/shell/env.go b/pkg/shell/env.go
index fbc8f5bb..2dabae61 100644
--- a/pkg/shell/env.go
+++ b/pkg/shell/env.go
@@ -12,17 +12,19 @@ func ReplaceEnvVars(text string) string {
 		key := match[2 : len(match)-1]
 
 		var def string
+		var dok bool
+
 		i := strings.IndexByte(key, ':')
 		if i > 0 {
 			key, def = key[:i], key[i+1:]
+			dok = true
 		}
 
-		value, exists := os.LookupEnv(key)
-		if exists {
+		if value, vok := os.LookupEnv(key); vok {
 			return value
 		}
 
-		if def != "" {
+		if dok {
 			return def
 		}