fancier variable interpolation

common/os_filesystem.go

@@ -5,6 +5,7 @@ import (
 	"path/filepath"
 
 	"github.com/mitchellh/go-homedir"
+	"go.spiff.io/expand"
 )
 
 type OsFilesystem struct{}
@@ -19,7 +20,7 @@ func (*OsFilesystem) GetAbsolutePath(path string) string {
 	if err == nil {
 		path = absPath
 	}
-	return os.ExpandEnv(path)
+	return expand.Expand(path, os.LookupEnv)
 }
 
 // returns (exists, isDir)

common/os_filesystem_test.go

@@ -63,7 +63,7 @@ func getEnvVarPath() string {
 	if runtime.GOOS == "windows" {
 		return "%" + interpolatedVar + "%"
 	}
-	return fmt.Sprintf("${%s}", interpolatedVar)
+	return fmt.Sprintf("${%s:-shouldNotMatter}", interpolatedVar)
 }
 
 func createTempFile(t *testing.T) *os.File {

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/spf13/cobra v1.8.0
 	github.com/stretchr/testify v1.8.4
 	github.com/zyedidia/generic v1.2.1
+	go.spiff.io/expand v1.1.0
 )
 
 require (

go.sum

@@ -70,8 +70,8 @@ github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcU
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/zyedidia/generic v1.2.1 h1:Zv5KS/N2m0XZZiuLS82qheRG4X1o5gsWreGb0hR7XDc=
 github.com/zyedidia/generic v1.2.1/go.mod h1:ly2RBz4mnz1yeuVbQA/VFwGjK3mnHGRj1JuoG336Bis=
-golang.org/x/exp v0.0.0-20231214170342-aacd6d4b4611 h1:qCEDpW1G+vcj3Y7Fy52pEM1AWm3abj8WimGYejI3SC4=
-golang.org/x/exp v0.0.0-20231214170342-aacd6d4b4611/go.mod h1:iRJReGqOEeBhDZGkGbynYwcHlctCvnjTYIamk7uXpHI=
+go.spiff.io/expand v1.1.0 h1:DseUwDcllRql2XIgEAepsodeCSBPul2fTrKpwswCR1I=
+go.spiff.io/expand v1.1.0/go.mod h1:HtW3QveGpZ/RGJ2KtOdFrJsb/0aFYi69AoBnN+YRFAc=
 golang.org/x/exp v0.0.0-20231226003508-02704c960a9b h1:kLiC65FbiHWFAOu+lxwNPujcsl8VYyTYYEZnsOO1WK4=
 golang.org/x/exp v0.0.0-20231226003508-02704c960a9b/go.mod h1:iRJReGqOEeBhDZGkGbynYwcHlctCvnjTYIamk7uXpHI=
 golang.org/x/sync v0.5.0 h1:60k92dhOjHxJkrqnwsfl8KuaHbn/5dl0lUPUklKo3qE=