Fixes issue 221 (#222)

https://github.com/lemire/simdjson/issues/221

jsonchecker/pass19.json

@@ -0,0 +1 @@
+-1

src/parsedjson.cpp

@@ -35,9 +35,11 @@ ParsedJson::ParsedJson(ParsedJson && p)
 
 WARN_UNUSED
 bool ParsedJson::allocateCapacity(size_t len, size_t maxdepth) {
-    if ((maxdepth == 0) || (len == 0)) {
-      std::cerr << "capacities must be non-zero " << std::endl;
-      return false;
+    if (maxdepth <= 0) {
+      maxdepth = 1; // don't let the user allocate nothing
+    }
+    if (len <= 0) {
+      len = 64; // allocating 0 bytes is wasteful.
     }
     if(len > SIMDJSON_MAXSIZE_BYTES) {
       return false;

tools/json2json.cpp

@@ -86,8 +86,8 @@ int main(int argc, char *argv[]) {
     return EXIT_FAILURE;
   }
   int res = simdjson::json_parse(p, pj); // do the parsing, return false on error
-  if (res) {
-    std::cerr << " Parsing failed. " << std::endl;
+  if (res != simdjson::SUCCESS) {
+    std::cerr << " Parsing failed. Error is '" << simdjson::errorMsg(res) << "'." << std::endl;
     return EXIT_FAILURE;
   }
   if (apidump) {

tools/jsonstats.cpp

@@ -46,6 +46,7 @@ stat_t simdjson_computestats(const simdjson::padded_string &p) {
   simdjson::ParsedJson pj = simdjson::build_parsed_json(p);
   answer.valid = pj.isValid();
   if (!answer.valid) {
+    std::cerr << pj.getErrorMsg() << std::endl;
     return answer;
   }
   answer.backslash_count = count_backslash(reinterpret_cast<const uint8_t*>(p.data()), p.size());