Support Error.cause in logging (#160)

bytecodealliance · Oct 17, 2024 · 72ee41c · 72ee41c
1 parent 150501f
commit 72ee41c
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Showing 3 changed files with 33 additions and 1 deletion.
diff --git a/runtime/engine.cpp b/runtime/engine.cpp
@@ -67,6 +67,8 @@ using api::Engine;
 using api::EngineState;
 using api::EngineConfig;
 
+void dump_error(JSContext *cx, HandleValue error, bool *has_stack, FILE *fp);
+
 __attribute__((weak))
 bool debug_logging_enabled() { return DEBUG_LOGGING; }
 #define LOG(...)                                                                                   \
@@ -116,6 +118,29 @@ bool print_stack(JSContext *cx, FILE *fp) {
   return print_stack(cx, stackp, fp);
 }
 
+void print_cause(JSContext *cx, HandleValue error, FILE *fp) {
+  bool has_cause = false;
+
+  if (error.isObject()) {
+    RootedObject err(cx, &error.toObject());
+    if (!JS_HasProperty(cx, err, "cause", &has_cause)) {
+      return;
+    }
+
+    if (has_cause) {
+      JS::RootedValue cause_val(cx);
+      if (!JS_GetProperty(cx, err, "cause", &cause_val)) {
+        return;
+      }
+
+      fprintf(stderr, "Caused by: ");
+
+      bool has_stack;
+      dump_error(cx, cause_val, &has_stack, fp);
+    }
+  }
+}
+
 void dump_error(JSContext *cx, HandleValue error, bool *has_stack, FILE *fp) {
   bool reported = false;
   RootedObject stack(cx);
@@ -144,6 +169,8 @@ void dump_error(JSContext *cx, HandleValue error, bool *has_stack, FILE *fp) {
   } else {
     *has_stack = false;
   }
+
+  print_cause(cx, error, fp);
 }
 
 void dump_promise_rejection(JSContext *cx, HandleValue reason, HandleObject promise, FILE *fp) {

diff --git a/tests/e2e/runtime-err/expect_serve_stderr.txt b/tests/e2e/runtime-err/expect_serve_stderr.txt
@@ -3,3 +3,8 @@ stderr [0] :: runtime error
 stderr [0] :: Stack:
 stderr [0] ::   @runtime-err.js:6:13
 stderr [0] ::   @runtime-err.js:7:7
+stderr [0] :: Caused by: 
+stderr [0] :: error cause
+stderr [0] :: Stack:
+stderr [0] ::   @runtime-err.js:6:49
+stderr [0] ::   @runtime-err.js:7:7
diff --git a/tests/e2e/runtime-err/runtime-err.js b/tests/e2e/runtime-err/runtime-err.js
@@ -3,7 +3,7 @@ import { strictEqual, deepStrictEqual, throws } from "../../assert.js";
 addEventListener("fetch", (evt) =>
   evt.respondWith(
     (async () => {
-      throw new Error('runtime error');
+      throw new Error('runtime error', { cause: new Error('error cause') });
     })()
   )
 );