Tests/LibELF: Add basic test checking initializer ordering

Author: https://github.com/DanShaders
Commit: https://github.com/SerenityOS/serenity/commit/6894faac1f
Pull-request: https://github.com/SerenityOS/serenity/pull/24170
Reviewed-by: https://github.com/ADKaster ✅

Base/home/anon/.config/Tests.ini

@@ -2,7 +2,7 @@
 SkipDirectories=Kernel/Legacy Shell
 SkipRegex=^ue-.*$
 SkipTests=TestCommonmark function.sh
-NotTestsPattern=^.*(txt|frm|inc)$
+NotTestsPattern=^.*(txt|frm|inc|so|elf)$
 
 [test-js]
 Arguments=--show-progress=false

Tests/LibELF/CMakeLists.txt

@@ -3,10 +3,13 @@ set(CMAKE_SKIP_RPATH FALSE)
 macro(add_test_lib NAME FILE)
     add_library(${NAME} SHARED ${FILE})
     serenity_set_implicit_links(${NAME})
-    # Avoid execution by the test runner
-    install(TARGETS ${NAME}
-            DESTINATION usr/Tests/LibELF
-            PERMISSIONS OWNER_READ GROUP_READ WORLD_READ OWNER_WRITE GROUP_WRITE)
+    install(TARGETS ${NAME} DESTINATION usr/Tests/LibELF)
+endmacro()
+
+macro(add_test_exe NAME FILE)
+    add_executable(${NAME} ${FILE})
+    serenity_set_implicit_links(${NAME})
+    install(TARGETS ${NAME} DESTINATION usr/Tests/LibELF)
 endmacro()
 
 macro(add_dlopen_lib NAME FUNCTION)
@@ -28,6 +31,7 @@ unset(CMAKE_INSTALL_RPATH)
 set(TEST_SOURCES
     test-elf.cpp
     TestDlOpen.cpp
+    TestOrder.cpp
     TestTLS.cpp
     TestWeakSymbolResolution.cpp
 )
@@ -48,3 +52,20 @@ add_test_lib(TestWeakSymbolResolution1 TestWeakSymbolResolution1.cpp)
 add_test_lib(TestWeakSymbolResolution2 TestWeakSymbolResolution2.cpp)
 target_link_libraries(TestWeakSymbolResolution PRIVATE TestWeakSymbolResolution1 TestWeakSymbolResolution2)
 set_target_properties(TestWeakSymbolResolution PROPERTIES INSTALL_RPATH "$ORIGIN")
+
+add_test_lib(TestOrderLib1 TestOrderLib1.cpp)
+add_test_lib(TestOrderLib2 TestOrderLib2.cpp)
+target_link_libraries(TestOrderLib2 PRIVATE TestOrderLib1)
+set_target_properties(TestOrderLib2 PROPERTIES INSTALL_RPATH "$ORIGIN")
+
+# NOTE: This is so ugly because CMake sorts targets supplied to target_link_libraries.
+#       .elf extension here avoids direct invocations by SerenityOS's test runner.
+add_test_exe(TestOrderExe1.elf TestOrderExe.cpp)
+target_link_libraries(TestOrderExe1.elf PRIVATE $<TARGET_FILE:TestOrderLib1> $<TARGET_FILE:TestOrderLib2>)
+add_dependencies(TestOrderExe1.elf TestOrderLib1 TestOrderLib2)
+set_target_properties(TestOrderExe1.elf PROPERTIES INSTALL_RPATH "$ORIGIN")
+
+add_test_exe(TestOrderExe2.elf TestOrderExe.cpp)
+target_link_libraries(TestOrderExe2.elf PRIVATE $<TARGET_FILE:TestOrderLib2> $<TARGET_FILE:TestOrderLib1>)
+add_dependencies(TestOrderExe2.elf TestOrderLib1 TestOrderLib2)
+set_target_properties(TestOrderExe2.elf PROPERTIES INSTALL_RPATH "$ORIGIN")

Tests/LibELF/TestOrder.cpp

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2024, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/LexicalPath.h>
+#include <LibCore/Process.h>
+#include <LibFileSystem/TempFile.h>
+#include <LibTest/TestCase.h>
+
+auto temp_directory = [] {
+    return MUST(FileSystem::TempFile::create_temp_directory());
+}();
+
+static ByteBuffer run(ByteString executable)
+{
+    static auto path_to_captured_output = LexicalPath::join(temp_directory->path(), "output"sv);
+
+    auto process = MUST(Core::Process::spawn(Core::ProcessSpawnOptions {
+        .executable = move(executable),
+        .file_actions = {
+            Core::FileAction::OpenFile {
+                .path = path_to_captured_output.string(),
+                .mode = Core::File::OpenMode::Write,
+                .fd = 1,
+            },
+        },
+    }));
+    MUST(process.wait_for_termination());
+    auto output = MUST(Core::File::open(path_to_captured_output.string(), Core::File::OpenMode::Read));
+    return MUST(output->read_until_eof());
+}
+
+TEST_CASE(order)
+{
+    {
+        auto expected = R"(TestOrderLib1.cpp:init
+TestOrderLib2.cpp:init
+TestOrderExe.cpp:init
+TestOrderExe.cpp:main
+f() returns: TestOrderLib1.cpp
+)"sv;
+        auto output = run("TestOrderExe1.elf");
+        EXPECT_EQ(StringView(output.bytes()), expected);
+    }
+
+    {
+        auto expected = R"(TestOrderLib1.cpp:init
+TestOrderLib2.cpp:init
+TestOrderExe.cpp:init
+TestOrderExe.cpp:main
+f() returns: TestOrderLib2.cpp
+)"sv;
+        auto output = run("TestOrderExe2.elf");
+        EXPECT_EQ(StringView(output.bytes()), expected);
+    }
+}

Tests/LibELF/TestOrderExe.cpp

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2024, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Format.h>
+
+[[gnu::constructor]] static void init()
+{
+    outln("TestOrderExe.cpp:init");
+}
+
+StringView f();
+
+int main()
+{
+    outln("TestOrderExe.cpp:main");
+    outln("f() returns: {}", f());
+}

Tests/LibELF/TestOrderLib1.cpp

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2024, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Format.h>
+
+[[gnu::constructor]] static void init()
+{
+    outln("TestOrderLib1.cpp:init");
+}
+
+StringView f();
+StringView f()
+{
+    return "TestOrderLib1.cpp"sv;
+}

Tests/LibELF/TestOrderLib2.cpp

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2024, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Format.h>
+
+[[gnu::constructor]] static void init()
+{
+    outln("TestOrderLib2.cpp:init");
+}
+
+StringView f();
+StringView f()
+{
+    return "TestOrderLib2.cpp"sv;
+}