[GR-17077] Thread.report_on_exception should be true by default.

PullRequest: truffleruby/944

Author: eregon

CHANGELOG.md

@@ -13,6 +13,7 @@ Compatibility:
 * `FFI::Struct#[]=` is now supported for inline character arrays.
 * `blocking: true` is now supported for `FFI::Library#attach_function`.
 * Implemented `Proc#>>` and `#<<` (#1688).
+* `Thread.report_on_exception` is now `true` by default like MRI 2.5+.
 
 Changes:
 

spec/tags/core/thread/report_on_exception_tags.txt

@@ -1,3 +1,2 @@
 slow:Thread.report_on_exception defaults to false
-fails:Thread.report_on_exception defaults to true
-fails:Thread#report_on_exception returns true for the main Thread
+slow:Thread.report_on_exception defaults to true

src/main/java/org/truffleruby/core/thread/ThreadManager.java

@@ -293,7 +293,7 @@ private static void setException(RubyContext context, DynamicObject thread, Dyna
         if (thread != mainThread) {
             final boolean isSystemExit = Layouts.BASIC_OBJECT.getLogicalClass(exception) == context.getCoreLibrary().getSystemExitClass();
 
-            if (!isSystemExit && (boolean) ReadObjectFieldNode.read(thread, "@report_on_exception", false)) {
+            if (!isSystemExit && (boolean) ReadObjectFieldNode.read(thread, "@report_on_exception", true)) {
                 context.send(context.getCoreLibrary().getTruffleThreadOperationsModule(),
                         "report_exception",
                         thread,

src/main/ruby/truffleruby/core/thread.rb

@@ -202,7 +202,7 @@ def self.handle_interrupt(config, &block)
   end
 
   @abort_on_exception = false
-  @report_on_exception = false
+  @report_on_exception = true
 
   class << self
     attr_accessor :abort_on_exception, :report_on_exception