improve error handling in data readers

Device/Histo/IntensityDataIOFactory.cpp

@@ -76,7 +76,7 @@ IHistogram* IntensityDataIOFactory::readIntensityData(const std::string& file_na
 {
     std::unique_ptr<OutputData<double>> data(readOutputData(file_name));
     if (!data)
-        throw std::runtime_error("Could not read " + file_name);
+        throw std::runtime_error("Cannot read intensity data from file: " + file_name);
     return IHistogram::createHistogram(*data);
 }
 
@@ -115,12 +115,9 @@ void IntensityDataIOFactory::writeOutputData(const std::string& file_name,
 #endif
 
     if (!fout.is_open())
-        throw std::runtime_error("IntensityDataIOFactory::writeOutputData() -> Error. "
-                                 "Can't open file '"
-                                 + file_name + "' for writing.");
+        throw std::runtime_error("Cannot open file for writing: " + file_name);
     if (!fout.good())
-        throw std::runtime_error("IntensityDataIOFactory::writeOutputData() -> Error! "
-                                 "File is not good, probably it is a directory.");
+        throw std::runtime_error("File is not good, probably it is a directory: " + file_name);
     std::stringstream ss;
     writeData(ss);
 
@@ -173,7 +170,7 @@ IntensityDataIOFactory::readOutputData(const std::string& file_name,
 {
 
     if (!BaseUtils::Filesystem::IsFileExists(file_name))
-        return nullptr;
+        throw std::runtime_error("File does not exist: " + file_name);
 
     using namespace DataUtils::Format;
     std::ifstream input_stream;
@@ -188,12 +185,9 @@ IntensityDataIOFactory::readOutputData(const std::string& file_name,
 #endif
 
     if (!input_stream.is_open())
-        throw std::runtime_error(
-            "IntensityDataIOFactory::getFromFilteredStream() -> Error. Can't open file '"
-            + file_name + "' for reading.");
+        throw std::runtime_error("Cannot open file for reading: " + file_name);
     if (!input_stream.good())
-        throw std::runtime_error("IntensityDataIOFactory::getFromFilteredStream() -> Error! "
-                                 "File is not good, probably it is a directory.");
+        throw std::runtime_error("File is not good, probably it is a directory:" + file_name);
 
     boost::iostreams::filtering_streambuf<boost::iostreams::input> input_filtered;
     if (DataUtils::Format::isGZipped(file_name))

Tests/Unit/Device/ReadSANSDRawTest.cpp

@@ -2,16 +2,22 @@
 #include "Device/Data/OutputData.h"
 #include "BATesting.h"
 #include "Tests/GTestWrapper/google_test.h"
+#include <cstdio>
 
 class ReadSANSDRawTest : public ::testing::Test {
 };
 
 TEST_F(ReadSANSDRawTest, Read)
 {
-    const auto fname = BATesting::ExampleDataDir() + "SANSDRaw.001";
+    const auto fname = BATesting::ExampleDataDir() + "/SANSDRaw.001";
     OutputData<double>* data =
         IntensityDataIOFactory::readOutputData(fname, IntensityDataIOFactory::automatic);
+    EXPECT_NE(data, nullptr);
+    if (!data)
+        return;
     EXPECT_EQ(data->rank(), 2);
     EXPECT_EQ(data->getAllocatedSize(), 16384);
-    EXPECT_EQ((*data)[128*128-1], 3);
+    for(int i=0; i<16384; ++i)
+        printf("%5i %5i\n", i, (int)(*data)[i]);
+    EXPECT_EQ((*data)[64*64-1], 3);
 }