Merge pull request #20 from vladimir-mencl-eresearch/master

Allow empty default values - solves #19
kreuzwerker · Jan 26, 2016 · e58fe8a · e58fe8a
2 parents 09df94b + 3fea4e8
commit e58fe8a
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Showing 2 changed files with 26 additions and 21 deletions.
diff --git a/envplate.go b/envplate.go
@@ -13,9 +13,10 @@ import (
 const (
 	NoDefaultDefined    = ""
 	NotAnEscapeSequence = ""
+	DefaultValueSyntax  = ":-"
 )
 
-var exp = regexp.MustCompile(`(\\*)\$\{(.+?)(?:\:\-(.+?))?\}`)
+var exp = regexp.MustCompile(`(\\*)\$\{(.+?)(?:(\:\-)(.*?))?\}`)
 
 func Apply(globs []string) {
 
@@ -95,7 +96,7 @@ func parse(file string) error {
 	parsed := exp.ReplaceAllStringFunc(string(content), func(match string) string {
 
 		var (
-			esc, key, def     = capture(match)
+			esc, key, sep, def     = capture(match)
 			value, keyDefined = env[key]
 		)
 
@@ -115,7 +116,7 @@ func parse(file string) error {
 
 		if !keyDefined {
 
-			if def == NoDefaultDefined {
+			if sep == NoDefaultDefined {
 				Log(ERROR, "'%s' requires undeclared environment variable '%s', no default is given", file, key)
 			} else {
 
@@ -162,15 +163,16 @@ func parse(file string) error {
 
 }
 
-func capture(s string) (esc, key, def string) {
+func capture(s string) (esc, key, sep, def string) {
 
 	matches := exp.FindStringSubmatch(s)
 
 	esc = matches[1]
 	key = matches[2]
-	def = matches[3]
+	sep = matches[3]
+	def = matches[4]
 
-	return esc, key, def
+	return esc, key, sep, def
 
 }
 

diff --git a/envplate_test.go b/envplate_test.go
@@ -55,7 +55,8 @@ func _template_defaults(t *testing.T) (string, string) {
 
 	tpl := `Double1=${DATABASE} Double2=${DATABASE}
   Double3=${DATABASE:-db2.example.com} Double4=${DATABASE:-db2.example.com}
-  DoubleDefault1=${ANOTHER_DATABASE:-db2-example.com} DoubleDefault2=${ANOTHER_DATABASE:-db2-example.com}`
+  DoubleDefault1=${ANOTHER_DATABASE:-db2-example.com} DoubleDefault2=${ANOTHER_DATABASE:-db2-example.com}
+  EmptyDefault=${UNDEFINED_VARIABLE:-}`
 
 	return _write(t, "parse.txt", tpl, 0644), tpl
 
@@ -206,7 +207,8 @@ func TestFullParseDefaults(t *testing.T) {
 	assert.True(_exists(backup))
 	assert.Equal(`Double1=db.example.com Double2=db.example.com
   Double3=db.example.com Double4=db.example.com
-  DoubleDefault1=db2-example.com DoubleDefault2=db2-example.com`, _read(t, file))
+  DoubleDefault1=db2-example.com DoubleDefault2=db2-example.com
+  EmptyDefault=`, _read(t, file))
 
 }
 
@@ -269,27 +271,28 @@ func TestCapture(t *testing.T) {
 	assert := assert.New(t)
 
 	var tt = []struct {
-		in, e, v, d string
+		in, e, v, s, d string
 	}{
-		{"${FOO}", "", "FOO", NoDefaultDefined},
-		{"${FOO:-bar}", "", "FOO", "bar"},
-		{"${FOO:-at the bar}", "", "FOO", "at the bar"},
-		{"${FOO_3000:-near the bar}", "", "FOO_3000", "near the bar"},
-		{"${FOO:--1}", "", "FOO", "-1"},
-		{"${FOO:-http://www.example.com/bar/gar/war?a=b}", "", "FOO", "http://www.example.com/bar/gar/war?a=b"},
-		{`\${FOO}`, `\`, "FOO", NoDefaultDefined},
-		{`\\${FOO:-bar}`, `\\`, "FOO", "bar"},
-		{`\\\${FOO:-bar}`, `\\\`, "FOO", "bar"},
-		{`\\\\${FOO:-bar}`, `\\\\`, "FOO", "bar"},
-		{"foo${FOO}", "", "FOO", NoDefaultDefined},
+		{"${FOO}", "", "FOO", NoDefaultDefined, NoDefaultDefined},
+		{"${FOO:-bar}", "", "FOO", ":-", "bar"},
+		{"${FOO:-at the bar}", "", "FOO", ":-", "at the bar"},
+		{"${FOO_3000:-near the bar}", "", "FOO_3000", ":-", "near the bar"},
+		{"${FOO:--1}", "", "FOO", ":-", "-1"},
+		{"${FOO:-http://www.example.com/bar/gar/war?a=b}", "", "FOO", ":-", "http://www.example.com/bar/gar/war?a=b"},
+		{`\${FOO}`, `\`, "FOO", NoDefaultDefined, NoDefaultDefined},
+		{`\\${FOO:-bar}`, `\\`, "FOO", ":-", "bar"},
+		{`\\\${FOO:-bar}`, `\\\`, "FOO", ":-", "bar"},
+		{`\\\\${FOO:-bar}`, `\\\\`, "FOO", ":-", "bar"},
+		{"foo${FOO}", "", "FOO", NoDefaultDefined, NoDefaultDefined},
 	}
 
 	for _, tt := range tt {
 
-		e, v, d := capture(tt.in)
+		e, v, s, d := capture(tt.in)
 
 		assert.Equal(tt.e, e)
 		assert.Equal(tt.v, v)
+		assert.Equal(tt.s, s)
 		assert.Equal(tt.d, d)
 
 	}