More tests.

dmlc · Jun 13, 2020 · 05ddb8f · 05ddb8f
1 parent d45edc7
commit 05ddb8f
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Showing 3 changed files with 51 additions and 3 deletions.
diff --git a/include/xgboost/json_io.h b/include/xgboost/json_io.h
@@ -81,7 +81,11 @@ class JsonReader {
     std::string msg = "Expecting: \"";
     msg += c;
     msg += "\", got: \"";
-    msg += std::string {got} + " \"";
+    if (got == -1) {
+      msg += "EOF\"";
+    } else {
+      msg += std::to_string(got) + " \"";
+    }
     Error(msg);
   }
 

diff --git a/src/common/json.cc b/src/common/json.cc
@@ -412,6 +412,10 @@ void JsonReader::Error(std::string msg) const {
   msg += ", around character position: " + std::to_string(cursor_.Pos());
   msg += '\n';
 
+  if (cursor_.Pos() == 0) {
+    LOG(FATAL) << msg;
+  }
+
   constexpr size_t kExtend = 8;
   auto beg = static_cast<int64_t>(cursor_.Pos()) -
              static_cast<int64_t>(kExtend) < 0 ? 0 : cursor_.Pos() - kExtend;

diff --git a/tests/cpp/common/test_json.cc b/tests/cpp/common/test_json.cc
@@ -408,14 +408,54 @@ TEST(Json, LoadDump) {
 
   std::ofstream fout(path);
   ASSERT_TRUE(fout);
-  fout << out;
+  fout << out << std::flush;
 
   std::string new_buffer = common::LoadSequentialFile(path);
-  Json load_back {Json::Load(StringView(new_buffer.c_str(), new_buffer.size()))};
+  ASSERT_EQ(ori_buffer, new_buffer);
 
+  Json load_back {Json::Load(StringView(new_buffer.c_str(), new_buffer.size()))};
   ASSERT_EQ(load_back, origin);
 }
 
+TEST(Json, Invalid) {
+  {
+    std::string str = "}";
+    bool has_thrown = false;
+    try {
+      Json load{Json::Load(StringView(str.c_str(), str.size()))};
+    } catch (dmlc::Error const &e) {
+      std::string msg = e.what();
+      ASSERT_NE(msg.find("Unknown"), std::string::npos);
+      has_thrown = true;
+    };
+    ASSERT_TRUE(has_thrown);
+  }
+  {
+    std::string str = R"json({foo)json";
+    bool has_thrown = false;
+    try {
+      Json load{Json::Load(StringView(str.c_str(), str.size()))};
+    } catch (dmlc::Error const &e) {
+      std::string msg = e.what();
+      ASSERT_NE(msg.find("position: 1"), std::string::npos);
+      has_thrown = true;
+    };
+    ASSERT_TRUE(has_thrown);
+  }
+  {
+    std::string str = R"json({"foo")json";
+    bool has_thrown = false;
+    try {
+      Json load{Json::Load(StringView(str.c_str(), str.size()))};
+    } catch (dmlc::Error const &e) {
+      std::string msg = e.what();
+      ASSERT_NE(msg.find("EOF"), std::string::npos);
+      has_thrown = true;
+    };
+    ASSERT_TRUE(has_thrown);
+  }
+}
+
 // For now Json is quite ignorance about unicode.
 TEST(Json, CopyUnicode) {
   std::string json_str = R"json(