Merge pull request #134 from hashicorp/b-fuzz

Fix parser bugs found via fuzzing from GH-128

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 +332,42 @@ 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},
+		{"t=0t d {}", true, map[string]interface{}{"t": 0}},
+		{"v=0E0v d{}", true, map[string]interface{}{"v": float64(0)}},
+	}
+
+	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/ast/ast.go

@@ -133,6 +133,12 @@ type ObjectItem struct {
 }
 
 func (o *ObjectItem) Pos() token.Pos {
+	// I'm not entirely sure what causes this, but removing this causes
+	// a test failure. We should investigate at some point.
+	if len(o.Keys) == 0 {
+		return token.Pos{}
+	}
+
 	return o.Keys[0].Pos()
 }
 

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})
@@ -320,7 +331,7 @@ func (p *Parser) listType() (*ast.ListType, error) {
 			// get next list item or we are at the end
 			// do a look-ahead for line comment
 			p.scan()
-			if p.lineComment != nil {
+			if p.lineComment != nil && len(l.List) > 0 {
 				lit, ok := l.List[len(l.List)-1].(*ast.LiteralType)
 				if ok {
 					lit.LineComment = p.lineComment

hcl/parser/parser_test.go

@@ -332,6 +332,29 @@ func TestParse(t *testing.T) {
 	}
 }
 
+func TestParse_inline(t *testing.T) {
+	cases := []struct {
+		Value string
+		Err   bool
+	}{
+		{"t t e{{}}", true},
+		{"o{{}}", true},
+		{"t t e d N{{}}", true},
+		{"t t e d{{}}", true},
+		{"N{}N{{}}", true},
+		{"v\nN{{}}", true},
+		{"v=/\n[,", true},
+	}
+
+	for _, tc := range cases {
+		t.Logf("Testing: %q", tc.Value)
+		_, err := Parse([]byte(tc.Value))
+		if (err != nil) != tc.Err {
+			t.Fatalf("Input: %q\n\nError: %s\n\nAST: %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) {