Change io::Reader and company to return ReadError::Eof instead of 0.

It's debatable if Eof should be considered an error or not.
But it is pretty clear it generally is a special response that
needs special handling, so easier to keep with the unexpected lot.

Also keeps better at higher abstraction levels, such as the line
reader.

1 files changed, 4 insertions, 4 deletions

diff --git a/test/io.cc b/test/io.cc
index 843c83e..04d97d6 100644
--- a/test/io.cc
+++ b/test/io.cc
@@ -128,8 +128,8 @@ TEST_F(IoTest, read_empty) {
   ASSERT_TRUE(ret.has_value());
   std::string tmp(10, ' ');
   auto ret2 = ret.value()->read(tmp.data(), tmp.size());
-  ASSERT_TRUE(ret2.has_value());
-  EXPECT_EQ(0, ret2.value());
+  ASSERT_FALSE(ret2.has_value());
+  EXPECT_EQ(io::ReadError::Eof, ret2.error());
 }
 
 TEST_F(IoTest, skip_empty) {
@@ -138,8 +138,8 @@ TEST_F(IoTest, skip_empty) {
   auto ret = io::openat(dirfd(), "test");
   ASSERT_TRUE(ret.has_value());
   auto ret2 = ret.value()->skip(10);
-  ASSERT_TRUE(ret2.has_value());
-  EXPECT_EQ(0, ret2.value());
+  ASSERT_FALSE(ret2.has_value());
+  EXPECT_EQ(io::ReadError::Eof, ret2.error());
 }
 
 TEST_F(IoTest, read) {