adapt to custom matchers for expected<T, Error>

Signed-off-by: Junwang Zhao <[email protected]>

Author: zhjwpku

src/iceberg/file_io.h

@@ -49,8 +49,9 @@ class ICEBERG_EXPORT FileIO {
   virtual expected<std::string, Error> ReadFile(const std::string& file_location,
                                                 std::optional<size_t> length) {
     // The following line is to avoid Windows linker error LNK2019.
-    // If this function is defined as pure virtual function, the `unexpected<Error>` will
-    // not be instantiated and exported in libiceberg.
+    // If this function is defined as pure virtual function, the `expected<std::string,
+    // Error>` and `unexpected<Error>` will not be instantiated and exported in
+    // libiceberg.
     return unexpected<Error>{
         {.kind = ErrorKind::kNotImplemented, .message = "ReadFile not implemented"}};
   }
@@ -65,8 +66,8 @@ class ICEBERG_EXPORT FileIO {
   virtual expected<void, Error> WriteFile(const std::string& file_location,
                                           std::string_view content, bool overwrite) {
     // The following line is to avoid Windows linker error LNK2019.
-    // If this function is defined as pure virtual function, the `unexpected<Error>` will
-    // not be instantiated and exported in libiceberg.
+    // If this function is defined as pure virtual function, the `expected<void, Error>`
+    // will not be instantiated and exported in libiceberg.
     return unexpected<Error>{
         {.kind = ErrorKind::kNotImplemented, .message = "WriteFile not implemented"}};
   }

test/CMakeLists.txt

@@ -49,6 +49,6 @@ if(ICEBERG_BUILD_BUNDLE)
   add_executable(arrow_fs_file_io_test)
   target_sources(arrow_fs_file_io_test PRIVATE arrow_fs_file_io_test.cc)
   target_link_libraries(arrow_fs_file_io_test PRIVATE iceberg_bundle_static
-                                                      GTest::gtest_main)
+                                                      GTest::gtest_main GTest::gmock)
   add_test(NAME arrow_fs_file_io_test COMMAND arrow_fs_file_io_test)
 endif()

test/arrow_fs_file_io_test.cc

@@ -24,36 +24,46 @@
 #include <arrow/filesystem/localfs.h>
 #include <gtest/gtest.h>
 
+#include "matchers.h"
+
+namespace iceberg {
+
 class LocalFileIOTest : public testing::Test {
  protected:
   void SetUp() override {
-    local_fs_ = std::make_shared<arrow::fs::LocalFileSystem>();
+    local_fs_ = std::make_shared<::arrow::fs::LocalFileSystem>();
     file_io_ = std::make_shared<iceberg::arrow::io::ArrowFileSystemFileIO>(local_fs_);
   }
 
-  std::shared_ptr<arrow::fs::LocalFileSystem> local_fs_;
+  std::shared_ptr<::arrow::fs::LocalFileSystem> local_fs_;
   std::shared_ptr<iceberg::FileIO> file_io_;
   std::filesystem::path tmpfile = std::filesystem::temp_directory_path() / "123.txt";
 };
 
 TEST_F(LocalFileIOTest, ReadWriteFile) {
   auto read_res = file_io_->ReadFile(tmpfile.string(), 1024);
-  EXPECT_EQ(read_res.error().kind, iceberg::ErrorKind::kInvalidArgument);
+  EXPECT_THAT(read_res, IsError(ErrorKind::kInvalidArgument));
+  EXPECT_THAT(read_res, HasErrorMessage("Length is not supported"));
 
   read_res = file_io_->ReadFile(tmpfile.string(), std::nullopt);
-  EXPECT_EQ(read_res.error().kind, iceberg::ErrorKind::kIOError);
+  EXPECT_THAT(read_res, IsError(ErrorKind::kIOError));
+  EXPECT_THAT(read_res, HasErrorMessage("No such file or directory"));
 
   auto write_res = file_io_->WriteFile(tmpfile.string(), "hello world", false);
-  EXPECT_TRUE(write_res.has_value());
+  EXPECT_THAT(write_res, IsOk());
 
   read_res = file_io_->ReadFile(tmpfile.string(), std::nullopt);
+  EXPECT_THAT(read_res, IsOk());
   EXPECT_EQ(read_res.value(), "hello world");
 }
 
 TEST_F(LocalFileIOTest, DeleteFile) {
   auto del_res = file_io_->DeleteFile(tmpfile.string());
-  EXPECT_TRUE(del_res.has_value());
+  EXPECT_THAT(del_res, IsOk());
 
   del_res = file_io_->DeleteFile(tmpfile.string());
-  EXPECT_EQ(del_res.error().kind, iceberg::ErrorKind::kIOError);
+  EXPECT_THAT(del_res, IsError(ErrorKind::kIOError));
+  EXPECT_THAT(del_res, HasErrorMessage("No such file or directory"));
 }
+
+}  // namespace iceberg