From b6626eed577806b1d635616f0481603cbbde737e Mon Sep 17 00:00:00 2001
From: Paul Hinze <phinze@phinze.com>
Date: Wed, 9 Dec 2015 18:05:49 -0600
Subject: [PATCH] config: friendlier error message on resource arity mismatch

closes #2072
---
 config/loader_hcl.go                           |  5 +++--
 config/loader_test.go                          | 11 +++++++++++
 config/test-fixtures/resource-arity-mistake.tf |  5 +++++
 3 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 config/test-fixtures/resource-arity-mistake.tf

diff --git a/config/loader_hcl.go b/config/loader_hcl.go
index c62ca3731..59fe81795 100644
--- a/config/loader_hcl.go
+++ b/config/loader_hcl.go
@@ -406,8 +406,9 @@ func loadResourcesHcl(list *ast.ObjectList) ([]*Resource, error) {
 	// all of the actual resources.
 	for _, item := range list.Items {
 		if len(item.Keys) != 2 {
-			// TODO: bad error message
-			return nil, fmt.Errorf("resource needs exactly 2 names")
+			return nil, fmt.Errorf(
+				"position %s: resource must be followed by exactly two strings, a type and a name",
+				item.Pos())
 		}
 
 		t := item.Keys[0].Token.Value().(string)
diff --git a/config/loader_test.go b/config/loader_test.go
index 4c291f6e9..6dbcfbede 100644
--- a/config/loader_test.go
+++ b/config/loader_test.go
@@ -45,6 +45,17 @@ func TestLoadFile_badType(t *testing.T) {
 	}
 }
 
+func TestLoadFile_resourceArityMistake(t *testing.T) {
+	_, err := LoadFile(filepath.Join(fixtureDir, "resource-arity-mistake.tf"))
+	if err == nil {
+		t.Fatal("should have error")
+	}
+	expected := "Error loading test-fixtures/resource-arity-mistake.tf: position 2:10: resource must be followed by exactly two strings, a type and a name"
+	if err.Error() != expected {
+		t.Fatalf("expected:\n%s\ngot:\n%s", expected, err)
+	}
+}
+
 func TestLoadFileWindowsLineEndings(t *testing.T) {
 	testFile := filepath.Join(fixtureDir, "windows-line-endings.tf")
 
diff --git a/config/test-fixtures/resource-arity-mistake.tf b/config/test-fixtures/resource-arity-mistake.tf
new file mode 100644
index 000000000..14e49ddf8
--- /dev/null
+++ b/config/test-fixtures/resource-arity-mistake.tf
@@ -0,0 +1,5 @@
+# I forgot the resource name!
+resource "aws_instance" {
+  ami = "ami-abc123"
+  instance_type = "t2.micro"
+}