Print unit test stack traces if encountered

Author: ianfixes

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - `LibraryProperties` to read metadata from Arduino libraries
 - `CppLibrary.library_properties_path`, `CppLibrary.library_properties?`, `CppLibrary.library_properties` to expose library properties of a Cpp library
 - `CppLibrary.arduino_library_dependencies` to list the dependent libraries specified by the library.properties file
+- `CppLibrary.print_stack_dump` prints stack trace dumps (on Windows specifically) to the console if encountered
 
 ### Changed
 - Move repository from https://github.com/ianfixes/arduino_ci to https://github.com/Arduino-CI/arduino_ci

lib/arduino_ci/cpp_library.rb

@@ -421,14 +421,31 @@ def build_for_test_with_configuration(test_file, aux_libraries, gcc_binary, ci_g
       executable
     end
 
+    # print any found stack dumps
+    # @param executable [Pathname] the path to the test file
+    def print_stack_dump(executable)
+      possible_dumpfiles = [
+        executable.sub_ext(executable.extname + ".stackdump")
+      ]
+      possible_dumpfiles.select(&:exist?).each do |dump|
+        puts "========== Stack dump from #{dump}:"
+        File.foreach(dump) { |line| print "    #{line}" }
+      end
+    end
+
     # run a test file
-    # @param [Pathname] the path to the test file
+    # @param executable [Pathname] the path to the test file
     # @return [bool] whether all tests were successful
     def run_test_file(executable)
       @last_cmd = executable
       @last_out = ""
       @last_err = ""
-      Host.run_and_output(executable.to_s.shellescape)
+      ret = Host.run_and_output(executable.to_s.shellescape)
+
+      # print any stack traces found during a failure
+      print_stack_dump(executable) unless ret
+
+      ret
     end
 
   end