Add read_compound method

3 files changed, 33 insertions, 6 deletions

diff --git a/include/io/stream_reader.h b/include/io/stream_reader.h
index 75dba6dddb..330d9c5c69 100644
--- a/include/io/stream_reader.h
+++ b/include/io/stream_reader.h
@@ -22,6 +22,7 @@
 
 #include "endian_str.h"
 #include "tag.h"
+#include "tagfwd.h"
 #include <iosfwd>
 #include <memory>
 #include <stdexcept>
@@ -57,6 +58,12 @@ public:
     endian::endian get_endian() const;
 
     /**
+     * @brief Reads a named tag from the stream, making sure that it is a compound
+     * @throw input_error on failure, or if the tag in the stream is not a compound
+     */
+    std::pair<std::string, std::unique_ptr<tag_compound>> read_compound();
+
+    /**
      * @brief Reads a named tag from the stream
      * @throw input_error on failure
      */
diff --git a/src/io/stream_reader.cpp b/src/io/stream_reader.cpp
index 541a416d83..15f29dba1d 100644
--- a/src/io/stream_reader.cpp
+++ b/src/io/stream_reader.cpp
@@ -18,6 +18,8 @@
  * along with libnbt++.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include "io/stream_reader.h"
+#include "make_unique.h"
+#include "tag_compound.h"
 #include <istream>
 
 namespace nbt
@@ -39,6 +41,19 @@ endian::endian stream_reader::get_endian() const
     return endian;
 }
 
+std::pair<std::string, std::unique_ptr<tag_compound>> stream_reader::read_compound()
+{
+    if(read_type() != tag_type::Compound)
+    {
+        is.setstate(std::ios::failbit);
+        throw input_error("Tag is not a compound");
+    }
+    std::string key = read_string();
+    auto comp = make_unique<tag_compound>();
+    comp->read_payload(*this);
+    return {std::move(key), std::move(comp)};
+}
+
 std::pair<std::string, std::unique_ptr<tag>> stream_reader::read_tag()
 {
     tag_type type = read_type();
diff --git a/test/read_test.cpp b/test/read_test.cpp
index ae900a502d..d95c762d43 100644
--- a/test/read_test.cpp
+++ b/test/read_test.cpp
@@ -140,10 +140,9 @@ void test_read_bigtest()
     ASSERT(file);
     nbt::io::stream_reader reader(file);
 
-    auto pair = reader.read_tag();
+    auto pair = reader.read_compound();
     ASSERT(pair.first == "Level");
-    ASSERT(pair.second->get_type() == tag_type::Compound);
-    verify_bigtest_structure(pair.second->as<tag_compound>());
+    verify_bigtest_structure(*pair.second);
 }
 
 void test_read_littletest()
@@ -153,10 +152,10 @@ void test_read_littletest()
     ASSERT(file);
     nbt::io::stream_reader reader(file, endian::little);
 
-    auto pair = reader.read_tag();
+    auto pair = reader.read_compound();
     ASSERT(pair.first == "Level");
     ASSERT(pair.second->get_type() == tag_type::Compound);
-    verify_bigtest_structure(pair.second->as<tag_compound>());
+    verify_bigtest_structure(*pair.second);
 }
 
 void test_read_errors()
@@ -197,8 +196,14 @@ void test_read_misc()
     std::ifstream file;
     nbt::io::stream_reader reader(file);
 
+    //Toplevel tag other than compound
     file.open("toplevel_string", std::ios::binary);
-    ASSERT(file);
+    EXPECT_EXCEPTION(reader.read_compound(), io::input_error);
+    ASSERT(!file);
+
+    //Rewind and try again with read_tag
+    file.clear();
+    ASSERT(file.seekg(0));
     auto pair = reader.read_tag();
     ASSERT(pair.first == "Test (toplevel tag_string)");
     ASSERT(*pair.second == tag_string(