Only convert CRLF to LF and not plain CR.

Git only converts CRLF to LF and not CR so to produce
the same SHA as git we must do the same.

Framework/Kernel/inc/MantidKernel/ChecksumHelper.h

@@ -10,8 +10,7 @@
 #include "MantidKernel/DllConfig.h"
 #include <string>
 
-namespace Mantid {
-namespace Kernel {
+namespace Mantid::Kernel {
 
 /** ChecksumHelper : A selection of helper methods for calculating checksums
  */
@@ -30,7 +29,6 @@ MANTID_KERNEL_DLL std::string sha1FromFile(const std::string &filepath,
 MANTID_KERNEL_DLL std::string gitSha1FromFile(const std::string &filepath);
 } // namespace ChecksumHelper
 
-} // namespace Kernel
-} // namespace Mantid
+} // namespace Mantid::Kernel
 
 #endif /* MANTID_KERNEL_CHECKSUMHELPER_H_ */

Framework/Kernel/src/ChecksumHelper.cpp

@@ -14,12 +14,12 @@
 #include <fstream>
 #include <sstream>
 
-namespace Mantid {
-namespace Kernel {
+namespace {
 
-namespace ChecksumHelper {
-namespace // anonymous
-{
+// Unix line ending character
+constexpr auto EOL_LF = "\n";
+// Windows line ending sequence
+constexpr auto EOL_CRLF = "\r\n";
 
 /**
  * Create sha1 out of data and an optional header
@@ -57,20 +57,20 @@ std::string createMD5(const std::string &data, const std::string &header = "") {
 }
 } // namespace
 
+namespace Mantid::Kernel::ChecksumHelper {
+
 /** Creates a md5 checksum from a string
  * @param input The string to checksum
  * @returns a checksum string
  **/
-std::string md5FromString(const std::string &input) {
-  return ChecksumHelper::createMD5(input);
-}
+std::string md5FromString(const std::string &input) { return createMD5(input); }
 
 /** Creates a SHA-1 checksum from a string
  * @param input The string to checksum
  * @returns a checksum string
  **/
 std::string sha1FromString(const std::string &input) {
-  return ChecksumHelper::createSHA1(input);
+  return createSHA1(input);
 }
 
 /** Creates a SHA-1 checksum from a file
@@ -82,7 +82,7 @@ std::string sha1FromFile(const std::string &filepath,
                          const bool unixEOL = false) {
   if (filepath.empty())
     return "";
-  return ChecksumHelper::createSHA1(loadFile(filepath, unixEOL));
+  return createSHA1(loadFile(filepath, unixEOL));
 }
 
 /** Creates a git checksum from a file (these match the git hash-object
@@ -102,7 +102,7 @@ std::string gitSha1FromFile(const std::string &filepath) {
   std::string contents = ChecksumHelper::loadFile(filepath, unixEOL);
   std::stringstream header;
   header << "blob " << contents.size() << '\0';
-  return ChecksumHelper::createSHA1(contents, header.str());
+  return createSHA1(contents, header.str());
 }
 
 /**
@@ -124,13 +124,13 @@ std::string loadFile(const std::string &filepath, const bool unixEOL = false) {
   filein.close();
 
   if (unixEOL) {
-    static boost::regex eol(
-        "\\R"); // \R is Perl syntax for matching any EOL sequence
-    contents = boost::regex_replace(contents, eol, "\n"); // converts all to LF
+    // convert CRLF to LF
+    // Old-style mac line endings are left alone by git:
+    // https://github.com/git/git/blob/bfdd66e72fffd18235757bedbf355fd4176d6019/convert.c#L1425
+    static boost::regex eol(EOL_CRLF);
+    contents = boost::regex_replace(contents, eol, EOL_LF);
   }
   return contents;
 }
 
-} // namespace ChecksumHelper
-} // namespace Kernel
-} // namespace Mantid
+} // namespace Mantid::Kernel::ChecksumHelper

Framework/Kernel/test/ChecksumHelperTest.h

@@ -75,7 +75,7 @@ public:
     Poco::File(filename).remove();
   }
 
-  void testGitSha1FromFileWithWindowsLineEndings() {
+  void testGitSha1FromFileWithWindowsLineEndingsFirstConvertsToLF() {
     const std::string filename(
         "ChecksumHelperTest_testGitSha1FromFileWithWindowsLineEndings.txt");
     const std::string data = "ChecksumHelperTest_"
@@ -89,6 +89,20 @@ public:
     Poco::File(filename).remove();
   }
 
+  void testGitSha1FromFileWithOldStyleMacLineEndingsDoesNotConvertToLF() {
+    const std::string filename(
+        "ChecksumHelperTest_testGitSha1FromFileWithOldStyleMacLineEndings.txt");
+    const std::string data = "ChecksumHelperTest_"
+                             "testGitSha1FromFileWithLinuxLineEndings\rTest "
+                             "this string out for size\r in a file";
+    createFile(filename, data);
+
+    std::string response = ChecksumHelper::gitSha1FromFile(filename);
+    TSM_ASSERT_EQUALS("The calculated git-hash is not as expected",
+                      "7b7e77332c1610df14fd26476d1601a22a34f11f", response);
+    Poco::File(filename).remove();
+  }
+
   void createFile(const std::string &fileName, const std::string &data) {
     // has to be saved as binary so it doesn't mess with line endings
     std::ofstream file(fileName.c_str(), std::ofstream::binary);