Bug 1958081 - [devtools] Cover JS Tracer stringification with the new JS Objects test framework. r=devtools-reviewers,nchevobbe

Differential Revision: https://phabricator.services.mozilla.com/D245075

devtools/client/webconsole/test/xpcshell/test_javascript_logging.js

@@ -0,0 +1,64 @@
+"use strict";
+
+const { JSObjectsTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/JSObjectsTestUtils.sys.mjs"
+);
+JSObjectsTestUtils.init(this);
+
+// Note that XPCShellContentUtils will already be initialized by JSObjectsTestUtils
+const { XPCShellContentUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/XPCShellContentUtils.sys.mjs"
+);
+
+const EXPECTED_VALUES_FILE = "test_javascript_logging.snapshot.mjs";
+
+add_task(async function () {
+  // Create a content page in order to better simulate a real world page
+  const contentPage = await XPCShellContentUtils.loadContentPage(
+    "http://example.com/"
+  );
+
+  await JSObjectsTestUtils.runTest(EXPECTED_VALUES_FILE, async function (arg) {
+    // Because the test page runs in a content process, we have to execute most of the test logic via `spawn`
+    return contentPage.spawn([arg], async ({ context, expression }) => {
+      const { CONTEXTS } = ChromeUtils.importESModule(
+        "resource://testing-common/AllJavascriptTypes.mjs"
+      );
+      const { JSTracer } = ChromeUtils.importESModule(
+        "resource://devtools/server/tracer/tracer.sys.mjs"
+      );
+      const systemPrincipal =
+        Services.scriptSecurityManager.getSystemPrincipal();
+      const chromeSandbox = Cu.Sandbox(systemPrincipal);
+
+      let ref;
+      try {
+        if (context == CONTEXTS.CHROME) {
+          ref = Cu.evalInSandbox(
+            expression,
+            chromeSandbox,
+            null,
+            "test sandbox"
+          );
+        } else {
+          ref = this.content.eval(expression);
+        }
+      } catch (e) {
+        ref = e;
+      }
+
+      const str = JSTracer.objectToString(ref);
+
+      // Silence any async rejection
+      if (ref instanceof this.content.Promise) {
+        // eslint-disable-next-line max-nested-callbacks
+        ref.catch(function () {});
+      }
+
+      return str;
+    });
+  });
+
+  info("Close content page");
+  await contentPage.close();
+});

devtools/client/webconsole/test/xpcshell/xpcshell.toml

@@ -3,4 +3,8 @@ tags = "devtools"
 firefox-appdir = "browser"
 run-if = ["os != 'android'"]
 
+["test_javascript_logging.js"]
+support-files = ["test_javascript_logging.snapshot.mjs"]
+prefs = ["dom.security.https_first=false"] # JS HttpServer doesn't support https
+
 ["test_webconsole_l10n.js"]

devtools/server/tracer/tracer.sys.mjs

@@ -933,7 +933,7 @@ function objectToString(obj) {
   } else if (typeof obj === "function") {
     return `function ${obj.name || "anonymous"}()`;
   }
-  return obj;
+  return primitiveToString(obj);
 }
 
 function primitiveToString(value) {
@@ -952,7 +952,7 @@ function primitiveToString(value) {
   }
 
   // For all other types/cases, rely on native convertion to string
-  return value;
+  return String(value);
 }
 
 /**
@@ -1112,4 +1112,5 @@ export const JSTracer = {
   removeTracingListener,
   NEXT_INTERACTION_MESSAGE,
   DOM_MUTATIONS,
+  objectToString,
 };