Support multiple source directories in `srcdirref` file

* Locate test files in all source directories specified in `srcdirref`
* Allow overriding contents of `srcdirref` so the directory of another
  component (within the same repository) can be appended to share testfiles

cmake/modules/BasicConfig.cmake

@@ -344,7 +344,10 @@ endif ()
 # useful if there's a test target; this is for instance also used in mocked configuration of syncthingtray) -> add a file
 # called "srcdirref" to the build directory; this file contains the path of the sources so tests can easily find test files
 # contained in the source directory
-file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/srcdirref" "${CMAKE_CURRENT_SOURCE_DIR}")
+if (NOT META_SRCDIR_REFS)
+    set(META_SRCDIR_REFS "${CMAKE_CURRENT_SOURCE_DIR}")
+endif ()
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/srcdirref" "${META_SRCDIR_REFS}")
 # -> ensure the directory "testfiles" exists in the build directory; tests of my projects use it by default to create working
 # copies of testfiles
 file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/testfiles")

tests/testutils.cpp

@@ -178,7 +178,7 @@ TestApplication::TestApplication(int argc, const char *const *argv)
     }
     // -> find source directory
     if (auto testFilePathFromSrcDirRef = readTestfilePathFromSrcRef(); !testFilePathFromSrcDirRef.empty()) {
-        m_testFilesPaths.emplace_back(std::move(testFilePathFromSrcDirRef));
+        m_testFilesPaths.insert(m_testFilesPaths.end(), std::make_move_iterator(testFilePathFromSrcDirRef.begin()), std::make_move_iterator(testFilePathFromSrcDirRef.end()));
     }
     // -> try testfiles directory in working directory
     m_testFilesPaths.emplace_back("./testfiles/");
@@ -612,10 +612,11 @@ string TestApplication::readTestfilePathFromEnv()
  * \remarks That file is supposed to contain the path the the source directory. It is supposed to be stored by the build system in the
  *          same directory as the test executable. The CMake modules contained of these utilities ensure that's the case.
  */
-string TestApplication::readTestfilePathFromSrcRef()
+std::vector<std::string> TestApplication::readTestfilePathFromSrcRef()
 {
     // find the path of the current executable on platforms supporting "/proc/self/exe"; otherwise assume the current working directory
     // is the executable path
+    auto res = std::vector<std::string>();
     auto binaryPath = std::string();
 #if defined(CPP_UTILITIES_USE_STANDARD_FILESYSTEM) && defined(PLATFORM_UNIX)
     try {
@@ -628,25 +629,30 @@ string TestApplication::readTestfilePathFromSrcRef()
     const auto srcdirrefPath = binaryPath + "srcdirref";
     try {
         // read "srcdirref" file which should contain the path of the source directory
-        auto srcDirContent(readFile(srcdirrefPath, 2 * 1024));
+        const auto srcDirContent = readFile(srcdirrefPath, 2 * 1024);
         if (srcDirContent.empty()) {
             cerr << Phrases::Warning << "The file \"srcdirref\" is empty." << Phrases::EndFlush;
-            return string();
+            return res;
         }
-        srcDirContent += "/testfiles/";
 
-        // check whether the referenced source directory contains a "testfiles" directory
+        // check whether the referenced source directories contain a "testfiles" directory
-        if (!dirExists(srcDirContent)) {
+        const auto srcPaths = splitStringSimple<std::vector<std::string_view>>(srcDirContent, "\n");
-            cerr << Phrases::Warning
+        for (const auto &srcPath : srcPaths) {
-                 << "The source directory referenced by the file \"srcdirref\" does not contain a \"testfiles\" directory or does not exist."
+            auto testfilesPath = argsToString(srcPath, "/testfiles/");
-                 << Phrases::End << "Referenced source directory: " << srcDirContent << endl;
+            if (dirExists(testfilesPath)) {
-            return string();
+                res.emplace_back(std::move(testfilesPath));
+            } else {
+                cerr << Phrases::Warning
+                     << "The source directory referenced by the file \"srcdirref\" does not contain a \"testfiles\" directory or does not exist."
+                     << Phrases::End << "Referenced source directory: " << testfilesPath << endl;
+            }
+
         }
-        return srcDirContent;
+        return res;
 
     } catch (const std::ios_base::failure &e) {
         cerr << Phrases::Warning << "The file \"" << srcdirrefPath << "\" can not be opened: " << e.what() << Phrases::EndFlush;
     }
-    return string();
+    return res;
 }
 } // namespace CppUtilities

tests/testutils.h

@@ -52,7 +52,7 @@ public:
 
 private:
     static std::string readTestfilePathFromEnv();
-    static std::string readTestfilePathFromSrcRef();
+    static std::vector<std::string> readTestfilePathFromSrcRef();
 
     ArgumentParser m_parser;
     OperationArgument m_listArg;