From f2b03facd9820d4f405cec00b89ba6af3559c3e9 Mon Sep 17 00:00:00 2001
From: Daniela Engert <dani@ngrt.de>
Date: Sat, 3 Jul 2021 14:21:54 +0000
Subject: [PATCH] Include test sources to pick up functions and classes from
 the module rather than from the non-modular library which is baked into the
 `test-main` library. (#2356)

This averts linker problems:
 - strong ownership model: missing linker symbols
 - weak ownership model: duplicate linker symbols

Simplify `gtest-extra.cc` while at it.
---
 test/CMakeLists.txt |  4 ++--
 test/gtest-extra.cc |  7 +++----
 test/module-test.cc | 16 ++++++++++++++--
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 720bea19..0e8c59e2 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -41,7 +41,7 @@ function(add_fmt_test name)
       set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-weak-vtables)
     endif ()
   elseif (ADD_FMT_TEST_MODULE)
-    set(libs test-main test-module)
+    set(libs gtest test-module)
     set_source_files_properties(${name}.cc PROPERTIES OBJECT_DEPENDS test-module)
   else ()
     set(libs test-main fmt)
@@ -97,7 +97,7 @@ if (FMT_CAN_MODULE)
     $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
   enable_module(test-module)
 
-  add_fmt_test(module-test MODULE)
+  add_fmt_test(module-test MODULE test-main.cc)
   if (MSVC)
     target_compile_options(test-module PRIVATE /utf-8 /Zc:__cplusplus
                            /Zc:externConstexpr /Zc:inline)
diff --git a/test/gtest-extra.cc b/test/gtest-extra.cc
index dc542184..1d48a173 100644
--- a/test/gtest-extra.cc
+++ b/test/gtest-extra.cc
@@ -32,11 +32,10 @@ output_redirect::~output_redirect() FMT_NOEXCEPT {
 }
 
 void output_redirect::flush() {
-#  if EOF != -1
-#    error "FMT_RETRY assumes return value of -1 indicating failure"
-#  endif
   int result = 0;
-  FMT_RETRY(result, fflush(file_));
+  do {
+    result = fflush(file_);
+  } while (result == EOF && errno == EINTR);
   if (result != 0) throw fmt::system_error(errno, "cannot flush stream");
 }
 
diff --git a/test/module-test.cc b/test/module-test.cc
index 69b6099a..5d050406 100644
--- a/test/module-test.cc
+++ b/test/module-test.cc
@@ -35,18 +35,30 @@
 #  define FMT_USE_FCNTL 0
 #endif
 #define FMT_NOEXCEPT noexcept
+#if defined(_WIN32) && !defined(__MINGW32__)
+#  define FMT_POSIX(call) _##call
+#else
+#  define FMT_POSIX(call) call
+#endif
+#define FMT_OS_H_  // don't pull in os.h directly or indirectly
 
 import fmt;
 
 // check for macros leaking from BMI
 static bool macro_leaked =
-#if defined(FMT_CORE_H_) || defined(FMT_FORMAT_H)
+#if defined(FMT_CORE_H_) || defined(FMT_FORMAT_H_)
     true;
 #else
     false;
 #endif
 
-#include "gtest-extra.h"
+// Include sources to pick up functions and classes from the module rather than
+// from the non-modular library which is baked into the 'test-main' library.
+// This averts linker problems:
+// - strong ownership model: missing linker symbols
+// - weak ownership model: duplicate linker symbols
+#include "gtest-extra.cc"
+#include "util.cc"
 
 // an implicitly exported namespace must be visible [module.interface]/2.2
 TEST(module_test, namespace) {