examples: Move ReportAndClearException to boilerplate

This is a useful helper for quickly debugging embedding mistakes so more it to the boilerplate code.
mozilla-spidermonkey · Sep 1, 2020 · b27cd35 · b27cd35
1 parent 90389cd
commit b27cd35
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Showing 3 changed files with 24 additions and 19 deletions.
diff --git a/examples/boilerplate.cpp b/examples/boilerplate.cpp
@@ -19,6 +19,25 @@ JSObject* boilerplate::CreateGlobal(JSContext* cx) {
                             JS::FireOnNewGlobalHook, options);
 }
 
+// Helper to read current exception and dump to stderr.
+//
+// NOTE: This must be called with a JSAutoRealm (or equivalent) on the stack.
+void boilerplate::ReportAndClearException(JSContext* cx) {
+  JS::ExceptionStack stack(cx);
+  if (!JS::StealPendingExceptionStack(cx, &stack)) {
+    fprintf(stderr, "Uncatchable exception thrown, out of memory or something");
+    exit(1);
+  }
+
+  JS::ErrorReportBuilder report(cx);
+  if (!report.init(cx, stack, JS::ErrorReportBuilder::WithSideEffects)) {
+    fprintf(stderr, "Couldn't build error report");
+    exit(1);
+  }
+
+  JS::PrintError(cx, stderr, report, false);
+}
+
 // Initialize the JS environment, create a JSContext and run the example
 // function in that context. By default the self-hosting environment is
 // initialized as it is needed to run any JavaScript). If the 'initSelfHosting'

diff --git a/examples/boilerplate.h b/examples/boilerplate.h
@@ -8,6 +8,8 @@ extern const JSClassOps DefaultGlobalClassOps;
 
 JSObject* CreateGlobal(JSContext* cx);
 
+void ReportAndClearException(JSContext* cx);
+
 bool RunExample(bool (*task)(JSContext*), bool initSelfHosting = true);
 
 }  // namespace boilerplate
diff --git a/examples/repl.cpp b/examples/repl.cpp
@@ -69,11 +69,6 @@ class ReplGlobal {
 constexpr JSClass ReplGlobal::klass;
 constexpr JSFunctionSpec ReplGlobal::functions[];
 
-static void die(const char* why) {
-  std::cerr << "fatal error:" << why << std::endl;
-  exit(1);
-}
-
 std::string FormatString(JSContext* cx, JS::HandleString string) {
   std::string buf = "\"";
 
@@ -131,19 +126,6 @@ std::string FormatResult(JSContext* cx, JS::HandleValue value) {
   return bytes.get();
 }
 
-static void ReportAndClearException(JSContext* cx) {
-  /* Get exception object before printing and clearing exception. */
-  JS::ExceptionStack stack(cx);
-  if (!JS::StealPendingExceptionStack(cx, &stack))
-    die("Uncatchable exception thrown, out of memory or something");
-
-  JS::ErrorReportBuilder report(cx);
-  if (!report.init(cx, stack, JS::ErrorReportBuilder::WithSideEffects))
-    die("Couldn't build error report");
-
-  JS::PrintError(cx, stderr, report, false);
-}
-
 JSObject* ReplGlobal::create(JSContext* cx) {
   JS::RealmOptions options;
   JS::RootedObject global(cx,
@@ -207,7 +189,9 @@ void ReplGlobal::loop(JSContext* cx, JS::HandleObject global) {
                                             buffer.length()));
 
     if (!EvalAndPrint(cx, buffer, startline)) {
-      if (!priv(global)->m_shouldQuit) ReportAndClearException(cx);
+      if (!priv(global)->m_shouldQuit) {
+        boilerplate::ReportAndClearException(cx);
+      }
     }
 
     js::RunJobs(cx);