🐛 Ignore errors from unknown sources (#11816)

frontend/src/app/main/errors.cljs

@@ -588,13 +588,58 @@
     (and (string? stack)
          (str/includes? stack "posthog"))))
 
+;; Captures the script location of a stack frame: the part preceding
+;; ":line:column", in both the V8 ("at fn (location:1:2)") and the
+;; SpiderMonkey/JSC ("fn@location:1:2") formats.
+(def ^:private frame-location-rx
+  #"(?:at |[@(])([^\s()]+):\d+:\d+")
+
+(defn- stack-frames
+  "The frame lines of a stack trace, without the leading message line
+  that V8 puts before them."
+  [stack]
+  (into []
+        (comp (map str/trim)
+              (filter (fn [line]
+                        (or (str/starts-with? line "at ")
+                            (str/includes? line "@")))))
+        (str/lines stack)))
+
+(defn- located-frame?
+  "True when a stack frame names the script it belongs to. Code injected
+  into the page carries no script to name and reports `<anonymous>`."
+  [frame]
+  (when-let [location (second (re-find frame-location-rx frame))]
+    (not (str/starts-with? location "<"))))
+
+(defn- from-injected-code?
+  "True when the stack is blank, or has frames but none of them names a
+  script. Either way the error was raised by third-party code injected
+  into the page (an extension content script, a desktop wrapper, a
+  bookmarklet) rather than by application code. Firefox, for instance,
+  raises \"can't access dead object\" with a blank stack when an unloaded
+  extension's code runs.
+
+  Anything our own code calls keeps our frames further down the stack, so
+  a stack without a single named script never belongs to us and there is
+  nothing actionable on our side."
+  [cause]
+  (let [stack (.-stack cause)]
+    (and (string? stack)
+         (or (str/blank? stack)
+             (let [frames (stack-frames stack)]
+               (and (some? (seq frames))
+                    (not (some located-frame? frames))))))))
+
 (defn is-ignorable-exception?
-  "True when the error is known to be harmless (browser extensions, analytics,
+  "True when the error is known to be harmless (browser extensions, injected
-   React/extension DOM conflicts, etc.) and should NOT be surfaced to the user."
+   third-party code, analytics, React/extension DOM conflicts, etc.) and
+   should NOT be surfaced to the user."
   [cause]
   (let [message (ex-message cause)]
     (or (from-extension? cause)
         (from-posthog? cause)
+        (from-injected-code? cause)
         (= message "Possible side-effect in debug-evaluate")
         (= message "Unexpected end of input")
         (str/starts-with? message "invalid props on component")

frontend/test/frontend_tests/errors_test.cljs

@@ -10,8 +10,9 @@
    [cljs.test :as t :include-macros true]))
 
 (defn- make-error
-  "Create a JS Error-like object with the given name, message, and optional stack."
+  "Create a JS Error-like object with the given name, message, and optional
-  [error-name message & {:keys [stack] :or {stack ""}}]
+  stack. Without a stack, the error keeps the one the runtime gave it."
+  [error-name message & {:keys [stack]}]
   (let [err (js/Error. message)]
     (set! (.-name err) error-name)
     (when (some? stack)
@@ -93,3 +94,57 @@
   (t/testing "Regular TypeError is NOT ignorable"
     (let [cause (make-error "TypeError" "undefined is not a function")]
       (t/is (false? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-ignorable-injected-script
+  (t/testing "Errors raised by code injected into the page are ignorable"
+    (let [cause (make-error "TypeError" "Cannot read properties of undefined (reading 'get')"
+                            :stack (str "TypeError: Cannot read properties of undefined (reading 'get')\n"
+                                        "    at nativeVis (<anonymous>:5:35)\n"
+                                        "    at HTMLDocument.<anonymous> (<anonymous>:21:64)\n"
+                                        "    at <anonymous>:17:33"))]
+      (t/is (true? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-not-ignorable-injected-script-calling-into-app
+  (t/testing "Errors whose stack reaches application code are NOT ignorable"
+    (let [cause (make-error "TypeError" "Cannot read properties of undefined (reading 'get')"
+                            :stack (str "TypeError: Cannot read properties of undefined (reading 'get')\n"
+                                        "    at nativeVis (<anonymous>:5:35)\n"
+                                        "    at zLe (https://design.penpot.app/js/main.js:42:13)"))]
+      (t/is (false? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-not-ignorable-release-build-v8-stack
+  (t/testing "Application errors from a release build are NOT ignorable (V8 stack)"
+    ;; Frames as they appear in production: advanced-compiled names, an
+    ;; asset URL carrying the version query string, and a trailing frame
+    ;; without a function name.
+    (let [cause (make-error "TypeError" "Cannot read properties of null (reading 'toString')"
+                            :stack (str "TypeError: Cannot read properties of null (reading 'toString')\n"
+                                        "    at $app$main$ui$workspace$shapes$path$editor$path_editor_STAR_$$ "
+                                        "(https://design.penpot.app/js/main-workspace.js?version=2.18.0-RC5-1789051786:8580:99)\n"
+                                        "    at $re (https://design.penpot.app/js/libs.js?version=2.18.0-RC5-1789051786:150:48345)\n"
+                                        "    at https://design.penpot.app/js/libs.js?version=2.18.0-RC5-1789051786:150:125675"))]
+      (t/is (false? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-not-ignorable-release-build-spidermonkey-stack
+  (t/testing "Application errors from a release build are NOT ignorable (SpiderMonkey/JSC stack)"
+    ;; SpiderMonkey stacks carry no message line and name the script after
+    ;; an @ instead of wrapping it in parentheses.
+    (let [cause (make-error "InternalError" "too much recursion"
+                            :stack (str "$APP.$JSCompiler_prototypeAlias$$.$inode_lookup$"
+                                        "@https://design.penpot.app/js/shared.js?version=2.18.0-RC5-1789051786:23076:58\n"
+                                        "$app$common$types$container$get_component_shape$cljs$0core$0IFn$0_invoke$0arity$03$$"
+                                        "@https://design.penpot.app/js/shared.js?version=2.18.0-RC5-1789051786:7596:1"))]
+      (t/is (false? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-ignorable-blank-stack
+  (t/testing "Errors with a blank stack are ignorable"
+    ;; Firefox raises "can't access dead object" with an empty stack when
+    ;; code from an unloaded extension runs in the page.
+    (let [cause (make-error "TypeError" "can't access dead object" :stack "")]
+      (t/is (true? (errors/is-ignorable-exception? cause))))))
+
+(t/deftest test-not-ignorable-message-only-stack
+  (t/testing "Errors whose stack holds only the message line are NOT ignorable"
+    ;; V8 gives native rejections such as a failed fetch no frames at all.
+    (let [cause (make-error "TypeError" "Failed to fetch" :stack "TypeError: Failed to fetch")]
+      (t/is (false? (errors/is-ignorable-exception? cause))))))