From be83044f5967b2ca0e8b7d25bb1c239fb8708de1 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Fri, 23 May 2014 22:07:33 -0700
Subject: [PATCH] config: tests, error cases

---
 config/variable.go      |  8 ++++++
 config/variable_test.go | 58 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 config/variable_test.go

diff --git a/config/variable.go b/config/variable.go
index edf8b671c..e26fa85bb 100644
--- a/config/variable.go
+++ b/config/variable.go
@@ -1,6 +1,7 @@
 package config
 
 import (
+	"fmt"
 	"reflect"
 	"regexp"
 	"strings"
@@ -53,6 +54,13 @@ func (w *variableDetectWalker) Primitive(v reflect.Value) error {
 
 		var err error
 		var iv InterpolatedVariable
+		if strings.Index(key, ".") == -1 {
+			return fmt.Errorf(
+				"Interpolated variable '%s' has bad format. "+
+					"Did you mean 'var.%s'?",
+				key, key)
+		}
+
 		if strings.HasPrefix(key, "var.") {
 			iv, err = NewUserVariable(key)
 		} else {
diff --git a/config/variable_test.go b/config/variable_test.go
new file mode 100644
index 000000000..bef0f60af
--- /dev/null
+++ b/config/variable_test.go
@@ -0,0 +1,58 @@
+package config
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestVariableDetectWalker(t *testing.T) {
+	w := new(variableDetectWalker)
+
+	str := `foo ${var.bar}`
+	if err := w.Primitive(reflect.ValueOf(str)); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(w.Variables) != 1 {
+		t.Fatalf("bad: %#v", w.Variables)
+	}
+	if w.Variables["var.bar"].(*UserVariable).FullKey() != "var.bar" {
+		t.Fatalf("bad: %#v", w.Variables)
+	}
+}
+
+func TestVariableDetectWalker_bad(t *testing.T) {
+	w := new(variableDetectWalker)
+
+	str := `foo ${bar}`
+	if err := w.Primitive(reflect.ValueOf(str)); err == nil {
+		t.Fatal("should error")
+	}
+}
+
+func TestVariableDetectWalker_escaped(t *testing.T) {
+	w := new(variableDetectWalker)
+
+	str := `foo $${var.bar}`
+	if err := w.Primitive(reflect.ValueOf(str)); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(w.Variables) > 0 {
+		t.Fatalf("bad: %#v", w.Variables)
+	}
+}
+
+func TestVariableDetectWalker_empty(t *testing.T) {
+	w := new(variableDetectWalker)
+
+	str := `foo`
+	if err := w.Primitive(reflect.ValueOf(str)); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(w.Variables) > 0 {
+		t.Fatalf("bad: %#v", w.Variables)
+	}
+}
+