builder: handle certain classes of JSON errors gracefully

Docker-DCO-1.1-Signed-off-by: Erik Hollensbe <github@hollensbe.org> (github: erikh)

builder/parser/line_parsers.go

@@ -91,10 +91,11 @@ func parseJSON(rest string) (*Node, error) {
 
 	for _, str := range myJson {
 		switch str.(type) {
-		case []interface{}:
-			return nil, dockerFileErrJSONNesting
+		case string:
 		case float64:
 			str = strconv.FormatFloat(str.(float64), 'G', -1, 64)
+		default:
+			return nil, dockerFileErrJSONNesting
 		}
 		next.Value = str.(string)
 		next.Next = blankNode()
@@ -115,6 +116,7 @@ func parseMaybeJSON(rest string) (*Node, error) {
 
 	if strings.HasPrefix(rest, "[") {
 		node, err := parseJSON(rest)
+
 		if err == nil {
 			return node, nil
 		} else if err == dockerFileErrJSONNesting {

builder/parser/parser_test.go

@@ -37,7 +37,7 @@ func TestTestNegative(t *testing.T) {
 
 		_, err = Parse(df)
 		if err == nil {
-			t.Fatalf("No error parsing broken dockerfile for %s: %s", dir.Name(), err.Error())
+			t.Fatalf("No error parsing broken dockerfile for %s", dir.Name())
 		}
 
 		df.Close()

builder/parser/testfiles/jeztah-invalid-json-json-inside-string-double/Dockerfile

@@ -0,0 +1 @@
+CMD "[\"echo\", \"Phew, I just managed to escaped those double quotes\"]"

builder/parser/testfiles/jeztah-invalid-json-json-inside-string-double/result

@@ -0,0 +1 @@
+(cmd "\"[\\\"echo\\\", \\\"Phew, I just managed to escaped those double quotes\\\"]\"")

builder/parser/testfiles/jeztah-invalid-json-json-inside-string/Dockerfile

@@ -0,0 +1 @@
+CMD '["echo", "Well, JSON in a string is JSON too?"]'

builder/parser/testfiles/jeztah-invalid-json-json-inside-string/result

@@ -0,0 +1 @@
+(cmd "'[\"echo\", \"Well, JSON in a string is JSON too?\"]'")

builder/parser/testfiles/jeztah-invalid-json-single-quotes/Dockerfile

@@ -0,0 +1 @@
+CMD ['echo','single quotes are invalid JSON']

builder/parser/testfiles/jeztah-invalid-json-single-quotes/result

@@ -0,0 +1 @@
+(cmd "['echo','single quotes are invalid JSON']")

builder/parser/testfiles/jeztah-invalid-json-unterminated-bracket/Dockerfile

@@ -0,0 +1 @@
+CMD ["echo", "Please, close the brackets when you're done"

builder/parser/testfiles/jeztah-invalid-json-unterminated-bracket/result

@@ -0,0 +1 @@
+(cmd "[\"echo\", \"Please, close the brackets when you're done\"")

builder/parser/testfiles/jeztah-invalid-json-unterminated-string/Dockerfile

@@ -0,0 +1 @@
+CMD ["echo", "look ma, no quote!]

builder/parser/testfiles/jeztah-invalid-json-unterminated-string/result

@@ -0,0 +1 @@
+(cmd "[\"echo\", \"look ma, no quote!]")