Remove the UnknownExceptionHandler director error handling class

Done in order to be C++17 compliant as it uses std::unexpected_handler
which was removed in C++17. This class was intended for director
exception handling but was never used by SWIG and was never documented.

Closes #1538

3 files changed, 8 insertions, 76 deletions

diff --git a/CHANGES.current b/CHANGES.current
index 99b31d5c9..e0b7f0897 100644
--- a/CHANGES.current
+++ b/CHANGES.current
@@ -7,6 +7,14 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.0.1 (in progress)
 ===========================
 
+2019-06-24: wsfulton
+            [Python, Ruby] #1538 Remove the UnknownExceptionHandler class in order to be
+            C++17 compliant as it uses std::unexpected_handler which was removed in C++17.
+            This class was intended for director exception handling but was never used by
+            SWIG and was never documented.
+
+            *** POTENTIAL INCOMPATIBILITY ***
+
 2019-06-06: bkotzz
             [Java] #1552 Improve performance in Java std::vector constructor wrapper that takes
             a native Java array as input.
diff --git a/Lib/python/director.swg b/Lib/python/director.swg
index 36df302f1..9694c6233 100644
--- a/Lib/python/director.swg
+++ b/Lib/python/director.swg
@@ -199,45 +199,6 @@ namespace Swig {
     }
   };
 
-  /* unknown exception handler  */
-  class UnknownExceptionHandler {
-#ifdef SWIG_DIRECTOR_UEH
-    static void handler() {
-      try {
-        throw;
-      } catch (DirectorException& e) {
-        std::cerr << "SWIG Director exception caught:" << std::endl
-                  << e.what() << std::endl;
-      } catch (std::exception& e) {
-        std::cerr << "std::exception caught: "<< e.what() << std::endl;
-      } catch (...) {
-        std::cerr << "Unknown exception caught." << std::endl;
-      }
-
-      std::cerr << std::endl
-                << "Python interpreter traceback:" << std::endl;
-      PyErr_Print();
-      std::cerr << std::endl;
-
-      std::cerr << "This exception was caught by the SWIG UnknownExceptionHandler." << std::endl
-                << "Try using %feature(\"director:except\") to avoid reaching this point." << std::endl
-                << std::endl
-                << "Exception is being re-thrown, program will likely abort/terminate." << std::endl;
-      throw;
-    }
-
-  public:
-    std::terminate_handler old;
-    UnknownExceptionHandler(std::terminate_handler nh = handler) {
-      old = std::set_terminate(nh);
-    }
-
-    ~UnknownExceptionHandler() {
-      std::set_terminate(old);
-    }
-#endif
-  };
-
   /* type mismatch in the return value from a python method call */
   class DirectorTypeMismatchException : public DirectorException {
   public:
diff --git a/Lib/ruby/director.swg b/Lib/ruby/director.swg
index a0569785f..9395b8183 100644
--- a/Lib/ruby/director.swg
+++ b/Lib/ruby/director.swg
@@ -153,43 +153,6 @@ namespace Swig {
     }
   };
 
-  /* unknown exception handler  */
-  class UnknownExceptionHandler {
-#ifdef SWIG_DIRECTOR_UEH
-    static void handler() {
-      try {
-	throw;
-      } catch (DirectorException& e) {
-	std::cerr << "SWIG Director exception caught:" << std::endl
-		  << e.what() << std::endl;
-      } catch (std::exception& e) {
-	std::cerr << "std::exception caught: "<< e.what() << std::endl;
-      } catch (...) {
-	std::cerr << "Unknown exception caught." << std::endl;
-      }
-      std::cerr << std::endl
-		<< "Ruby interpreter traceback:" << std::endl;
-      std::cerr << std::endl;
-      std::cerr << "This exception was caught by the SWIG UnknownExceptionHandler." << std::endl
-		<< "Try using %feature(\"director:except\") to avoid reaching this point." << std::endl
-		<< std::endl
-		<< "Exception is being re-thrown, program will like abort/terminate." << std::endl;
-      throw;
-    }
-
-  public:
-    std::terminate_handler old;
-    UnknownExceptionHandler(std::terminate_handler nh = handler) {
-      old = std::set_terminate(nh);
-    }
-
-    ~UnknownExceptionHandler() {
-      std::set_terminate(old);
-    }
-#endif
-  };
-
-
   /* Type mismatch in the return value from a Ruby method call */
   class DirectorTypeMismatchException : public DirectorException {
   public: