initiator_mock.h

// Copyright 2022 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
 
#pragma once
 
#include <array>
#include <cstddef>
#include <optional>
 
#include "pw_bytes/span.h"
#include "pw_containers/to_array.h"
#include "pw_spi/initiator.h"
 
namespace pw::spi {
 
 
class MockTransaction {
 public:
  constexpr MockTransaction(Status expected_return_value,
                            ConstByteSpan write_buffer,
                            ConstByteSpan read_buffer)
      : return_value_(expected_return_value),
        read_buffer_(read_buffer),
        write_buffer_(write_buffer) {}
 
  ConstByteSpan read_buffer() const { return read_buffer_; }
 
  ConstByteSpan write_buffer() const { return write_buffer_; }
 
  Status return_value() const { return return_value_; }
 
 private:
  const Status return_value_;
  const ConstByteSpan read_buffer_;
  const ConstByteSpan write_buffer_;
};
 
constexpr MockTransaction MockReadTransaction(Status expected_return_value,
                                              ConstByteSpan read_buffer) {
  return MockTransaction(expected_return_value, ConstByteSpan(), read_buffer);
}
 
constexpr MockTransaction MockWriteTransaction(Status expected_return_value,
                                               ConstByteSpan write_buffer) {
  return MockTransaction(expected_return_value, write_buffer, ConstByteSpan());
}
 
class MockInitiator : public pw::spi::Initiator {
 public:
  explicit constexpr MockInitiator(span<MockTransaction> transaction_list)
      : expected_transactions_(transaction_list),
        expected_transaction_index_(0) {}
 
  Status Finalize() const {
    if (expected_transaction_index_ != expected_transactions_.size()) {
      return Status::OutOfRange();
    }
    return Status();
  }
 
  ~MockInitiator() override;
 
 private:
  span<MockTransaction> expected_transactions_;
  size_t expected_transaction_index_;
 
  pw::Status DoWriteRead(pw::ConstByteSpan, pw::ByteSpan) override;
 
  pw::Status DoConfigure(const pw::spi::Config& /*config */) override {
    return pw::OkStatus();
  }
};
 
template <size_t kSize>
constexpr std::array<MockTransaction, kSize> MakeExpectedTransactionArray(
    const MockTransaction (&transactions)[kSize]) {
  return containers::to_array(transactions);
}
 
}  // namespace pw::spi