Fix parsing of quoted strings

Pretty printing was not distinguishing between single-quote delimited strings and double-quote delimited strings, which in earlier revisions caused an exception which the latest revision caught and swallowed, but didn't really fix. This change refactors the prettyPrint method as a state machine which correctly handles both quoting and escaping within strings. The isEscaped method is eliminated.

json-path/src/main/java/com/jayway/jsonpath/internal/JsonFormatter.java

@@ -25,77 +25,96 @@ public class JsonFormatter {
 
     private static final String NEW_LINE = System.getProperty("line.separator");
 
+		private static final int MODE_SINGLE = 100;
+		private static final int MODE_DOUBLE = 101;
+		private static final int MODE_ESCAPE_SINGLE = 102;
+		private static final int MODE_ESCAPE_DOUBLE = 103;
+		private static final int MODE_BETWEEN = 104;
+
     private static void appendIndent(StringBuilder sb, int count) {
         for (; count > 0; --count) sb.append(INDENT);
     }
 
-    private static boolean isEscaped(StringBuilder sb, int index) {
-        boolean escaped = false;
-        int idx = Math.min(index, sb.length());
-        try {
-            while (idx > 0 && sb.charAt(--idx) == '\\') {
-                escaped = !escaped;
-            }
-        } catch (Exception e){
-            logger.warn("Failed to check escaped ", e);
-        }
-        return escaped;
-    }
-
     public static String prettyPrint(String input) {
 
         input = input.replaceAll("[\\r\\n]", "");
 
         StringBuilder output = new StringBuilder(input.length() * 2);
-        boolean quoteOpened = false;
+				int mode = MODE_BETWEEN;
         int depth = 0;
 
         for (int i = 0; i < input.length(); ++i) {
             char ch = input.charAt(i);
 
+						switch (mode) {
+								case MODE_BETWEEN:
 										switch (ch) {
 												case '{':
 												case '[':
 														output.append(ch);
-                    if (!quoteOpened) {
 														output.append(NEW_LINE);
 														appendIndent(output, ++depth);
-                    }
 														break;
 												case '}':
 												case ']':
-                    if (quoteOpened)
-                        output.append(ch);
-                    else {
 														output.append(NEW_LINE);
 														appendIndent(output, --depth);
 														output.append(ch);
-                    }
-                    break;
-                case '"':
-                case '\'':
-                    output.append(ch);
-                    if (quoteOpened) {
-                        if (!isEscaped(output, i))
-                            quoteOpened = false;
-                    } else quoteOpened = true;
 														break;
 												case ',':
 														output.append(ch);
-                    if (!quoteOpened) {
 														output.append(NEW_LINE);
 														appendIndent(output, depth);
-                    }
 														break;
 												case ':':
-                    if (quoteOpened) output.append(ch);
-                    else output.append(" : ");
+														output.append(" : ");
+														break;
+												case '\'':
+														output.append(ch);
+														mode = MODE_SINGLE;
+														break;
+												case '"':
+														output.append(ch);
+														mode = MODE_DOUBLE;
+														break;
+												case ' ':
 														break;
 												default:
-                    if (quoteOpened || !(ch == ' '))
 														output.append(ch);
 														break;
 										}
+										break;
+								case MODE_ESCAPE_SINGLE:
+										output.append(ch);
+										mode = MODE_SINGLE;
+										break;
+								case MODE_ESCAPE_DOUBLE:
+										output.append(ch);
+										mode = MODE_DOUBLE;
+										break;
+								case MODE_SINGLE:
+										output.append(ch);
+										switch (ch) {
+												case '\'':
+														mode = MODE_BETWEEN;
+														break;
+												case '\\':
+														mode = MODE_ESCAPE_SINGLE;
+														break;
+										}
+										break;
+								case MODE_DOUBLE:
+										output.append(ch);
+										switch (ch) {
+												case '"':
+														mode = MODE_BETWEEN;
+														break;
+												case '\\':
+														mode = MODE_ESCAPE_DOUBLE;
+														break;
+										}
+										break;
+            }
         }
         return output.toString();
     }