hcl/parser: don't allow objects with no keys

decoder_test.go

@@ -269,9 +269,7 @@ func TestDecode_interface(t *testing.T) {
 		{
 			"nested_provider_bad.hcl",
 			true,
-			// This is not ideal but without significant rework of the decoder
-			// we get a partial result back as well as an error.
-			map[string]interface{}{},
+			nil,
 		},
 
 		{
@@ -334,6 +332,44 @@ func TestDecode_interface(t *testing.T) {
 	}
 }
 
+func TestDecode_interfaceInline(t *testing.T) {
+	cases := []struct {
+		Value string
+		Err   bool
+		Out   interface{}
+	}{
+		{
+			"t t e{{}}",
+			true,
+			nil,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Logf("Testing: %q", tc.Value)
+
+		var out interface{}
+		err := Decode(&out, tc.Value)
+		if (err != nil) != tc.Err {
+			t.Fatalf("Input: %q\n\nError: %s", tc.Value, err)
+		}
+
+		if !reflect.DeepEqual(out, tc.Out) {
+			t.Fatalf("Input: %q. Actual, Expected.\n\n%#v\n\n%#v", tc.Value, out, tc.Out)
+		}
+
+		var v interface{}
+		err = Unmarshal([]byte(tc.Value), &v)
+		if (err != nil) != tc.Err {
+			t.Fatalf("Input: %q\n\nError: %s", tc.Value, err)
+		}
+
+		if !reflect.DeepEqual(v, tc.Out) {
+			t.Fatalf("Input: %q. Actual, Expected.\n\n%#v\n\n%#v", tc.Value, out, tc.Out)
+		}
+	}
+}
+
 func TestDecode_equal(t *testing.T) {
 	cases := []struct {
 		One, Two string

hcl/parser/parser.go

@@ -220,8 +220,19 @@ func (p *Parser) objectKey() ([]*ast.ObjectKey, error) {
 
 			return keys, nil
 		case token.LBRACE:
+			var err error
+
+			// If we have no keys, then it is a syntax error. i.e. {{}} is not
+			// allowed.
+			if len(keys) == 0 {
+				err = &PosError{
+					Pos: p.tok.Pos,
+					Err: fmt.Errorf("expected: IDENT | STRING got: %s", p.tok.Type),
+				}
+			}
+
 			// object
-			return keys, nil
+			return keys, err
 		case token.IDENT, token.STRING:
 			keyCount++
 			keys = append(keys, &ast.ObjectKey{Token: p.tok})

hcl/parser/parser_test.go

@@ -332,6 +332,22 @@ func TestParse(t *testing.T) {
 	}
 }
 
+func TestParse_inline(t *testing.T) {
+	cases := []struct {
+		Value string
+		Err   bool
+	}{
+		{"t t e{{}}", true},
+	}
+
+	for _, tc := range cases {
+		_, err := Parse([]byte(tc.Value))
+		if (err != nil) != tc.Err {
+			t.Fatalf("Input: %q\n\nError: %s", tc.Value, err)
+		}
+	}
+}
+
 // equals fails the test if exp is not equal to act.
 func equals(tb testing.TB, exp, act interface{}) {
 	if !reflect.DeepEqual(exp, act) {

json/parser/parser_test.go

@@ -332,6 +332,22 @@ func TestParse(t *testing.T) {
 	}
 }
 
+func TestParse_inline(t *testing.T) {
+	cases := []struct {
+		Value string
+		Err   bool
+	}{
+		{"{:{", true},
+	}
+
+	for _, tc := range cases {
+		_, err := Parse([]byte(tc.Value))
+		if (err != nil) != tc.Err {
+			t.Fatalf("Input: %q\n\nError: %s", tc.Value, err)
+		}
+	}
+}
+
 // equals fails the test if exp is not equal to act.
 func equals(tb testing.TB, exp, act interface{}) {
 	if !reflect.DeepEqual(exp, act) {