LineageOS/android_external_libcxx
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Implement LWG 2937 - equivalent("dne", "exists") is not an error

Browse Source 
This patch speculatively implements the PR for LWG 2937, which fixes
two issues with equivalent.

(1) It makes equivalent("dne", "exists") an error. Previously only
    equivalent("dne", "dne") was an error and the former case was not (it returned false).
    Now equivalent reports an error when either input doesn't exist.

(2) It makes equivalent(p1, p2) well-formed when `is_other(p1) && is_other(p2)`.
    Previously this was an error, but there is seemingly no reason why it should be on POSIX system.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@307117 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Fiselier
2017-07-05 03:37:05 +00:00
parent c5247b417b
commit 3288eac673
3 changed files with 86 additions and 59 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
src/experimental/filesystem/operations.cpp
View File

@@ -426,17 +426,20 @@ void __current_path(const path& p, std::error_code *ec) {
bool __equivalent(const path& p1, const path& p2, std::error_code *ec)
{
auto make_unsupported_error = [&]() {
set_or_throw(make_error_code(errc::not_supported), ec,
"equivalent", p1, p2);
return false;
};
std::error_code ec1, ec2;
struct ::stat st1 = {};
struct ::stat st2 = {};
auto s1 = detail::posix_stat(p1.native(), st1, &ec1);
if (!exists(s1))
return make_unsupported_error();
auto s2 = detail::posix_stat(p2.native(), st2, &ec2);
if ((!exists(s1) && !exists(s2)) || (is_other(s1) && is_other(s2))) {
set_or_throw(make_error_code(errc::not_supported), ec,
"equivalent", p1, p2);
return false;
}
if (!exists(s2))
return make_unsupported_error();
if (ec) ec->clear();
return (st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino);
}

52
test/std/experimental/filesystem/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
View File

@@ -26,16 +26,16 @@ using namespace std::experimental::filesystem;
TEST_SUITE(equivalent_test_suite)
TEST_CASE(signature_test)
{
const path p; ((void)p);
std::error_code ec; ((void)ec);
TEST_CASE(signature_test) {
const path p;
((void)p);
std::error_code ec;
((void)ec);
ASSERT_NOEXCEPT(equivalent(p, p, ec));
ASSERT_NOT_NOEXCEPT(equivalent(p, p));
}
TEST_CASE(equivalent_test)
{
TEST_CASE(equivalent_test) {
struct TestCase {
path lhs;
path rhs;
@@ -56,26 +56,37 @@ TEST_CASE(equivalent_test)
}
}
TEST_CASE(equivalent_reports_double_dne)
{
TEST_CASE(equivalent_reports_error_if_input_dne) {
const path E = StaticEnv::File;
const path DNE = StaticEnv::DNE;
{ // Test that no exception is thrown if one of the paths exists
TEST_CHECK(equivalent(E, DNE) == false);
TEST_CHECK(equivalent(DNE, E) == false);
{ // Test that an error is reported when either of the paths don't exist
std::error_code ec = GetTestEC();
TEST_CHECK(equivalent(E, DNE, ec) == false);
TEST_CHECK(ec);
TEST_CHECK(ec != GetTestEC());
}
{
std::error_code ec = GetTestEC();
TEST_CHECK(equivalent(DNE, E, ec) == false);
TEST_CHECK(ec);
TEST_CHECK(ec != GetTestEC());
}
{
TEST_CHECK_THROW(filesystem_error, equivalent(DNE, E));
TEST_CHECK_THROW(filesystem_error, equivalent(E, DNE));
}
{ // Test that an exception is thrown if both paths do not exist.
TEST_CHECK_THROW(filesystem_error, equivalent(DNE, DNE));
}
{
std::error_code ec;
std::error_code ec = GetTestEC();
TEST_CHECK(equivalent(DNE, DNE, ec) == false);
TEST_CHECK(ec);
TEST_CHECK(ec != GetTestEC());
}
}
TEST_CASE(equivalent_is_other_succeeds)
{
TEST_CASE(equivalent_hardlink_succeeds) {
scoped_test_env env;
path const file = env.create_file("file", 42);
const path hl1 = env.create_hardlink(file, "hl1");
@@ -85,4 +96,17 @@ TEST_CASE(equivalent_is_other_succeeds)
TEST_CHECK(equivalent(hl1, hl2));
}
TEST_CASE(equivalent_is_other_succeeds) {
scoped_test_env env;
path const file = env.create_file("file", 42);
const path sock1 = env.create_socket("sock1");
const path sock2 = env.create_socket("sock2");
// Required to test behavior for inputs where is_other(p) is true.
TEST_REQUIRE(is_other(sock1));
TEST_CHECK(!equivalent(file, sock1));
TEST_CHECK(!equivalent(sock2, file));
TEST_CHECK(!equivalent(sock1, sock2));
TEST_CHECK(equivalent(sock1, sock1));
}
TEST_SUITE_END()

4
www/upcoming_meeting.html
View File

@@ -64,7 +64,7 @@
<tr><td><a href="http://wg21.link/LWG2597">2597</a></td><td>std::log misspecified for complex numbers</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2783">2783</a></td><td>stack::emplace() and queue::emplace() should return decltype(auto)</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2932">2932</a></td><td>Constraints on parallel algorithm implementations are underspecified</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2937">2937</a></td><td>Is equivalent("existing_thing", "not_existing_thing") an error?</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2937">2937</a></td><td>Is equivalent("existing_thing", "not_existing_thing") an error?</td><td>Toronto</td><td>Complete</td></tr>
<tr><td><a href="http://wg21.link/LWG2940">2940</a></td><td>result_of specification also needs a little cleanup</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2942">2942</a></td><td>LWG 2873's resolution missed weak_ptr::owner_before</td><td>Toronto</td><td></td></tr>
<tr><td><a href="http://wg21.link/LWG2954">2954</a></td><td>Specialization of the convenience variable templates should be prohibited</td><td>Toronto</td><td></td></tr>
@@ -84,7 +84,7 @@
<li>2597 - I think we do this already; probably needs tests</li>
<li>2783 - should be easy to change; needs tests</li>
<li>2932 - We're not doing the parallel algorithms yet.</li>
<li>2937 - file system; Eric?</li>
<li>2937 - Implemented with tests. The PR LGTM (Eric)</li>
<li>2940 - We haven't implemented result_of yet, but I don't think that this will require any changes.</li>
<li>2942 - all of our owner_before overloads are already noexcept; just need to update the tests.</li>
<li>2954 - I don't think there's anything to do here.</li>