feat(test): improved op sanitizer errors + traces (#13676)

This commit improves the error messages for the `deno test` async op
sanitizer. It does this in two ways:
- it uses handwritten error messages for each op that could be leaking
- it includes traces showing where each op was started

This "async op tracing" functionality is a new feature in deno_core.
It likely has a significant performance impact, which is why it is only
enabled in tests.

1 files changed, 23 insertions, 0 deletions

diff --git a/core/lib.deno_core.d.ts b/core/lib.deno_core.d.ts
index 9f554f12b..37cd33190 100644
--- a/core/lib.deno_core.d.ts
+++ b/core/lib.deno_core.d.ts
@@ -141,5 +141,28 @@ declare namespace Deno {
     ): undefined | UncaughtExceptionCallback;
 
     export type UncaughtExceptionCallback = (err: any) => void;
+
+    /**
+     * Enables collection of stack traces of all async ops. This allows for
+     * debugging of where a given async op was started. Deno CLI uses this for
+     * improving error message in op sanitizer errors for `deno test`.
+     *
+     * **NOTE:** enabling tracing has a significant negative performance impact.
+     * To get high level metrics on async ops with no added performance cost,
+     * use `Deno.core.metrics()`.
+     */
+    function enableOpCallTracing(): void;
+
+    export interface OpCallTrace {
+      opName: string;
+      stack: string;
+    }
+
+    /**
+     * A map containing traces for all ongoing async ops. The key is the op id.
+     * Tracing only occurs when `Deno.core.enableOpCallTracing()` was previously
+     * enabled.
+     */
+    const opCallTraces: Map<number, OpCallTrace>;
   }
 }