It is inconvenient to be unable to print a padded_string. (#713)

* It is inconvenient to be unable to print a padded_string.

* Allows us to print the padded_string even when it is embedded in result object when exceptions are enabled.

include/simdjson/document.h

@@ -1215,7 +1215,16 @@ inline std::ostream& operator<<(std::ostream& out, const simdjson_result<dom::ar
  *        thrown).
  */
 inline std::ostream& operator<<(std::ostream& out, const simdjson_result<dom::object> &value) noexcept(false) { return out << minify<simdjson_result<dom::object>>(value); }
-
+/**
+ * Send padded_string instance to an output stream.
+ *
+ * @param out The output stream.
+ * @param s The padded_string instance.
+  * @throw simdjson_error if the result being printed has an error. If there is an error with the
+ *        underlying output stream, that error will be propagated (simdjson_error will not be
+ *        thrown).
+ */
+inline std::ostream& operator<<(std::ostream& out, simdjson_result<padded_string> &s) noexcept(false) { return out << s.value(); }
 #endif
 
 /** The result of a JSON navigation that may fail. */

include/simdjson/padded_string.h

@@ -7,6 +7,7 @@
 #include <cstring>
 #include <memory>
 #include <string>
+#include <ostream>
 
 namespace simdjson {
 
@@ -110,6 +111,15 @@ private:
 
 }; // padded_string
 
+/**
+ * Send padded_string instance to an output stream.
+ *
+ * @param out The output stream.
+ * @param s The padded_string instance.
+ * @throw if there is an error with the underlying output stream. simdjson itself will not throw.
+ */
+inline std::ostream& operator<<(std::ostream& out, const padded_string& s) { return out << s.data(); }
+
 } // namespace simdjson
 
 // This is deliberately outside of simdjson so that people get it without having to use the namespace

tests/basictests.cpp

@@ -1607,7 +1607,7 @@ namespace format_tests {
   const string MINIFIED(R"({"foo":1,"bar":[1,2,3],"baz":{"a":1,"b":2,"c":3}})");
   bool assert_minified(ostringstream &actual, const std::string &expected=MINIFIED) {
     if (actual.str() != expected) {
-      cerr << "Failed to correctly minify " << DOCUMENT.data() << endl;
+      cerr << "Failed to correctly minify " << DOCUMENT << endl;
       cerr << "Expected: " << expected << endl;
       cerr << "Actual:   " << actual.str() << endl;
       return false;