Fix errors on empty stacktraces

CHANGELOG.md

@@ -9,6 +9,7 @@
 
 ### Bugs fixed
 
+* [#3022](https://github.com/clojure-emacs/cider/issues/3022): Handle empty stacktraces, pointing users to docs about the OmitStackTraceInFastThrow JVM optimization.
 * [#3020](https://github.com/clojure-emacs/cider/issues/3020): Fix session linking on Windows, e.g. when jumping into a library on the classpath.
 * [#3031](https://github.com/clojure-emacs/cider/pull/3031): Fix `cider-eval-defun-up-to-point` failing to match delimiters correctly in some cases, resulting in reader exceptions.
 * [#3039](https://github.com/clojure-emacs/cider/pull/3039): Allow starting the sideloader for the tooling session

cider-stacktrace.el

@@ -677,30 +677,37 @@ others."
   "Emit into BUFFER function call site info for the stack FRAME.
 This associates text properties to enable filtering and source navigation."
   (with-current-buffer buffer
-    (nrepl-dbind-response frame (file line flags class method name var ns fn)
-      (let ((flags (mapcar 'intern flags))) ; strings -> symbols
-        (insert-text-button (format "%26s:%5d  %s/%s"
-                                    (if (member 'repl flags) "REPL" file) line
-                                    (if (member 'clj flags) ns class)
-                                    (if (member 'clj flags) fn method))
-                            'var var 'class class 'method method
-                            'name name 'file file 'line line
-                            'flags flags 'follow-link t
-                            'action 'cider-stacktrace-navigate
-                            'help-echo (cider-stacktrace-tooltip
-                                        "View source at this location")
-                            'font-lock-face 'cider-stacktrace-face
-                            'type 'cider-plain-button)
-        (save-excursion
-          (let ((p4 (point))
-                (p1 (search-backward " "))
-                (p2 (search-forward "/"))
-                (p3 (search-forward-regexp "[^/$]+")))
-            (put-text-property p1 p4 'font-lock-face 'cider-stacktrace-ns-face)
-            (put-text-property p2 p3 'font-lock-face 'cider-stacktrace-fn-face)
-            (put-text-property (line-beginning-position) (line-end-position)
-                               'cider-stacktrace-frame t)))
-        (insert "\n")))))
+    (if (null frame) ;; Probably caused by OmitStackTraceInFastThrow
+        (let ((url "https://docs.cider.mx/cider/troubleshooting.html#empty-java-stacktraces"))
+          (insert "  No stacktrace available!\n  Please see ")
+          (insert-text-button url
+                              'url url
+                              'follow-link t
+                              'action (lambda (x) (browse-url (button-get x 'url)))))
+      (nrepl-dbind-response frame (file line flags class method name var ns fn)
+        (let ((flags (mapcar 'intern flags))) ; strings -> symbols
+          (insert-text-button (format "%26s:%5d  %s/%s"
+                                      (if (member 'repl flags) "REPL" file) line
+                                      (if (member 'clj flags) ns class)
+                                      (if (member 'clj flags) fn method))
+                              'var var 'class class 'method method
+                              'name name 'file file 'line line
+                              'flags flags 'follow-link t
+                              'action 'cider-stacktrace-navigate
+                              'help-echo (cider-stacktrace-tooltip
+                                          "View source at this location")
+                              'font-lock-face 'cider-stacktrace-face
+                              'type 'cider-plain-button)
+          (save-excursion
+            (let ((p4 (point))
+                  (p1 (search-backward " "))
+                  (p2 (search-forward "/"))
+                  (p3 (search-forward-regexp "[^/$]+")))
+              (put-text-property p1 p4 'font-lock-face 'cider-stacktrace-ns-face)
+              (put-text-property p2 p3 'font-lock-face 'cider-stacktrace-fn-face)
+              (put-text-property (line-beginning-position) (line-end-position)
+                                 'cider-stacktrace-frame t)))
+          (insert "\n"))))))
 
 (defun cider-stacktrace-render-compile-error (buffer cause)
   "Emit into BUFFER the compile error CAUSE, and enable jumping to it."

doc/modules/ROOT/pages/troubleshooting.adoc

@@ -269,16 +269,10 @@ counting from 0 while Clojure starts from 1. Accordingly, the `cider-nrepl`
 middleware uses 1-based indexing and all conversions to 0-based indexing should
 be handled client-side. See https://github.com/clojure-emacs/cider/issues/2852.
 
-=== Empty Java stacktraces resulting in `NullPointerException`
+=== Empty Java stacktraces
 
-Occasionally the JVM might remove some stack frames, which will break
-CIDER's stacktrace display functionality, resulting in error message like these:
-
-[source]
-----
-error in process filter: cider-stacktrace-render-frame: Format specifier doesn’t match argument type
-error in process filter: Format specifier doesn’t match argument type
-----
+Occasionally the JVM might remove some stack frames, resulting in no stacktrace
+information being displayed in CIDER's error buffer.
 
 That's caused by an JVM optimization (`OmitStackTraceInFastThrow`, enabled by
 default), which optimizes "built-in" exceptions that are thrown frequently enough
@@ -287,4 +281,20 @@ to be cached and have no stacktrace.
 You can turn off the optimization by adding the JVM flag `-XX:-OmitStackTraceInFastThrow` to whatever
 command you're using to start nREPL.
 
+In particular, by adding it to a deps.edn file under an alias (eg. `:dev`)
+[source,lisp]
+---
+{:aliases
+ {:dev
+  {:jvm-opts ["-XX:-OmitStackTraceInFastThrow"]
+  ...}}}
+---
+
+Or by customising the jack-in options.
+[source,lisp]
+---
+(setq cider-clojure-cli-global-options "-J-XX:-OmitStackTraceInFastThrow")
+---
+
+
 TIP: You can read more about this problem https://github.com/clojure-emacs/cider/issues/3022[here].