Add a new incremental parsing API

Change-Id: I6b921766836d58df0281fb23b2add3f62a478e14

webm_parser/test_utils/element_parser_test.h

@@ -0,0 +1,114 @@
+// Copyright (c) 2016 The WebM project authors. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS.  All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+#ifndef TEST_UTILS_ELEMENT_PARSER_TEST_H_
+#define TEST_UTILS_ELEMENT_PARSER_TEST_H_
+
+#include <cstdint>
+#include <vector>
+
+#include "gtest/gtest.h"
+
+#include "test_utils/limited_reader.h"
+#include "test_utils/parser_test.h"
+#include "webm/buffer_reader.h"
+#include "webm/reader.h"
+#include "webm/status.h"
+
+namespace webm {
+
+// Base class for unit tests that test an instance of the ElementParser
+// inteface. The template parameter T is the parser class being tested, and the
+// optional id is the element ID associated with elements from the parser.
+template <typename T, Id id = static_cast<Id>(0)>
+class ElementParserTest : public ParserTest<T> {
+ public:
+  // Sets the reader's internal buffer to the given buffer and metadata_ to
+  // data.size().
+  void SetReaderData(std::vector<std::uint8_t> data) override {
+    metadata_.size = data.size();
+    ParserTest<T>::SetReaderData(std::move(data));
+  }
+
+  // Sets metadata_.size to size and then calls Init() on the parser, ensuring
+  // that it returns the expected status code.
+  void TestInit(std::uint64_t size, Status::Code expected) {
+    metadata_.size = size;
+    const Status status = parser_.Init(metadata_, metadata_.size);
+    ASSERT_EQ(expected, status.code);
+  }
+
+  // Similar to the base class implementation, but with the difference that
+  // Init() is also called (after setting metadata_.size to size).
+  void ParseAndVerify(std::uint64_t size) override {
+    TestInit(size, Status::kOkCompleted);
+
+    std::uint64_t num_bytes_read = 0;
+    const Status status = parser_.Feed(&callback_, &reader_, &num_bytes_read);
+    ASSERT_EQ(Status::kOkCompleted, status.code);
+
+    if (size != kUnknownElementSize) {
+      ASSERT_EQ(size, num_bytes_read);
+    }
+  }
+
+  void ParseAndVerify() override { ParseAndVerify(metadata_.size); }
+
+  void IncrementalParseAndVerify() override {
+    TestInit(metadata_.size, Status::kOkCompleted);
+
+    webm::LimitedReader limited_reader(
+        std::unique_ptr<webm::Reader>(new BufferReader(std::move(reader_))));
+
+    Status status;
+    std::uint64_t num_bytes_read = 0;
+    do {
+      limited_reader.set_total_read_skip_limit(1);
+      std::uint64_t local_num_bytes_read = 0;
+      status = parser_.Feed(&callback_, &limited_reader, &local_num_bytes_read);
+      num_bytes_read += local_num_bytes_read;
+      ASSERT_GE(1, local_num_bytes_read);
+    } while (status.code == Status::kWouldBlock ||
+             status.code == Status::kOkPartial);
+
+    ASSERT_EQ(Status::kOkCompleted, status.code);
+
+    if (metadata_.size != kUnknownElementSize) {
+      ASSERT_EQ(metadata_.size, num_bytes_read);
+    }
+  }
+
+  // Initializes the parser (after setting metadata_.size to size), ensures it
+  // succeeds, and then calls Feed() on the parser, making sure it returns the
+  // expected status code.
+  void ParseAndExpectResult(Status::Code expected, std::uint64_t size) {
+    TestInit(size, Status::kOkCompleted);
+
+    std::uint64_t num_bytes_read = 0;
+    const Status status = parser_.Feed(&callback_, &reader_, &num_bytes_read);
+    ASSERT_EQ(expected, status.code);
+  }
+
+  // Initializes the parser, ensures it succeeds, and then calls Feed() on the
+  // parser, making sure it returns the expected status code.
+  void ParseAndExpectResult(Status::Code expected) override {
+    ParseAndExpectResult(expected, metadata_.size);
+  }
+
+ protected:
+  using ParserTest<T>::callback_;
+  using ParserTest<T>::parser_;
+  using ParserTest<T>::reader_;
+
+  // Element metadata associated with the element parsed by parser_. This is
+  // passed to Init() when initializing the parser.
+  ElementMetadata metadata_ = {id, 0, 0, 0};
+};
+
+}  // namespace webm
+
+#endif  // TEST_UTILS_ELEMENT_PARSER_TEST_H_