Wee fuzz test and associated bug fixes

src/fuzz.cpp

@@ -0,0 +1,51 @@
+#include "minify.h"
+#include "parser3.h"
+
+void testStreaming(std::string const &json) {
+  MinifyState streaming;
+  MinifyState batch;
+  auto c = minifyCallbacks();
+  parser3::Status streamingStatus = parser3::S_OK;
+  parser3::Status batchStatus = parser3::S_OK;
+  do {
+    auto copy = json;
+    parser3::Parser3 parser(&c, &streaming);
+    for (int i = 0; i < copy.size(); ++i) {
+      auto s = parser.parse(copy.data() + i, 1);
+      if (s != parser3::S_AGAIN) {
+        streamingStatus = s;
+        break;
+      }
+    }
+    auto s = parser.parse(nullptr, 0);
+    if (s != parser3::S_OK) {
+      streamingStatus = s;
+      break;
+    }
+  } while (0);
+  do {
+    auto copy = json;
+    parser3::Parser3 parser(&c, &batch);
+    auto s = parser.parse(copy.data(), copy.size());
+    if (s != parser3::S_AGAIN) {
+      batchStatus = s;
+      break;
+    }
+    s = parser.parse(nullptr, 0);
+    if (s != parser3::S_OK) {
+      batchStatus = s;
+      break;
+    }
+  } while (0);
+  if (streamingStatus != batchStatus) {
+    abort();
+  }
+  if (streaming.result != batch.result) {
+    abort();
+  }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+  testStreaming(std::string((const char *)data, size));
+  return 0;
+}