text: //===- llvm/unittest/Support/raw_ostream_test.cpp - raw_ostream tests -----===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  
  #include "llvm/Support/Format.h"
  #include "llvm/Support/raw_sha1_ostream.h"
  #include "gtest/gtest.h"
  
  #include <string>
  
  using namespace llvm;
  
  static std::string toHex(StringRef Input) {
    static const char *const LUT = "0123456789ABCDEF";
    size_t Length = Input.size();
  
    std::string Output;
    Output.reserve(2 * Length);
    for (size_t i = 0; i < Length; ++i) {
      const unsigned char c = Input[i];
      Output.push_back(LUT[c >> 4]);
      Output.push_back(LUT[c & 15]);
    }
    return Output;
  }
  
  TEST(raw_sha1_ostreamTest, Basic) {
    llvm::raw_sha1_ostream Sha1Stream;
    Sha1Stream << "Hello World!";
    auto Hash = toHex(Sha1Stream.sha1());
  
    ASSERT_EQ("2EF7BDE608CE5404E97D5F042F95F89F1C232871", Hash);
  }
  
  TEST(sha1_hash_test, Basic) {
    ArrayRef<uint8_t> Input((const uint8_t *)"Hello World!", 12);
    std::array<uint8_t, 20> Vec = SHA1::hash(Input);
    std::string Hash = toHex({(const char *)Vec.data(), 20});
    ASSERT_EQ("2EF7BDE608CE5404E97D5F042F95F89F1C232871", Hash);
  }
  
  // Check that getting the intermediate hash in the middle of the stream does
  // not invalidate the final result.
  TEST(raw_sha1_ostreamTest, Intermediate) {
    llvm::raw_sha1_ostream Sha1Stream;
    Sha1Stream << "Hello";
    auto Hash = toHex(Sha1Stream.sha1());
  
    ASSERT_EQ("F7FF9E8B7BB2E09B70935A5D785E0CC5D9D0ABF0", Hash);
    Sha1Stream << " World!";
    Hash = toHex(Sha1Stream.sha1());
  
    // Compute the non-split hash separately as a reference.
    llvm::raw_sha1_ostream NonSplitSha1Stream;
    NonSplitSha1Stream << "Hello World!";
    auto NonSplitHash = toHex(NonSplitSha1Stream.sha1());
  
    ASSERT_EQ(NonSplitHash, Hash);
  }
  
  TEST(raw_sha1_ostreamTest, Reset) {
    llvm::raw_sha1_ostream Sha1Stream;
    Sha1Stream << "Hello";
    auto Hash = toHex(Sha1Stream.sha1());
  
    ASSERT_EQ("F7FF9E8B7BB2E09B70935A5D785E0CC5D9D0ABF0", Hash);
  
    Sha1Stream.resetHash();
    Sha1Stream << " World!";
    Hash = toHex(Sha1Stream.sha1());
  
    ASSERT_EQ("7447F2A5A42185C8CF91E632789C431830B59067", Hash);
  }
  