Clojure 1.10 REPL exception and error message changes

Clojure 1.10 saw changes in how certain errors are reported, in particular
reader/compiler related errors that happen at the REPL. Since CIDER is based on
a REPL interface, this changes the errors that CIDER sees.

Split the tests in separate 1.9 / 1.10 branches where appropriate.

Author: plexus

test/clj/cider/nrepl/middleware/inspect_test.clj

@@ -76,8 +76,13 @@
                                                :code "(first 1)"})]
 
       (testing "exprs that throw exceptions return an `ex` slot"
-        (is (= "class java.lang.Exception"
-               (:ex exception-response))))))
+        (is (= "class java.lang.IllegalArgumentException"
+               (:ex exception-response))))
+
+      ;;TODO: The :err slot is missing when running this through the Cider test-runner
+      (testing "exprs that throw exceptions return an `err` slot"
+        (is (.contains (:err exception-response)
+                       "IllegalArgumentException")))))
 
   (testing "inspect-pop error handling"
     (with-redefs [i/swap-inspector! (fn [& _] (throw (Exception. "pop exception")))]

test/clj/cider/nrepl/middleware/pprint_test.clj

@@ -84,8 +84,9 @@
                    :pprint "true"
                    :pprint-fn "cider.nrepl.middleware.pprint/fipp-pprint"}]
       (is (= "{nil [nil nil nil #{nil} nil nil nil]}\n"
-             (:pprint-out (session/message message))))))
+             (:pprint-out (session/message message)))))))
 
+(deftest wrap-pprint-custom-pprint-fn-test
   (testing "fipp-pprint respects the :print-meta slot"
     (is (= "^{:a :b}\n{}\n"
            (:pprint-out (session/message {:op :eval
@@ -122,8 +123,9 @@
                                           :code "^{:a :b} {}"
                                           :pprint "true"
                                           :pprint-fn "cider.nrepl.middleware.pprint/fipp-pprint"
-                                          :print-meta "true"})))))
+                                          :print-meta "true"}))))))
 
+(deftest ^{:max-clj-version "1.9.0"} wrap-pprint-resolve-pprint-fn-1.9-test
   (testing "non-resolvable pprint-fn"
     (testing "non-existing ns"
       (let [response (session/message {:op :eval
@@ -154,3 +156,38 @@
         (is (= (:ex response) "class java.lang.NullPointerException"))
         (is (= (:root-ex response) "class java.lang.NullPointerException"))
         (is (.startsWith (:err response) "NullPointerException   clojure.lang.Var.find"))))))
+
+(deftest ^{:min-clj-version "1.10.0"} wrap-pprint-resolve-pprint-fn-1.10-test
+  (testing "non-resolvable pprint-fn"
+    (testing "non-existing ns"
+      (let [response (session/message {:op :eval
+                                       :code "nil"
+                                       :pprint "true"
+                                       :pprint-fn "never-used-ns-example/pprint"})]
+        (is (= (:status response) #{"eval-error" "done"}))
+        (is (= (:ex response) "class clojure.lang.ExceptionInfo"))
+        (is (= (:root-ex response) "class java.lang.IllegalArgumentException"))
+
+        (is (.startsWith (:err response) "Error printing return value (IllegalArgumentException) at clojure.lang.Var/find "))
+        (is (.contains (:err response) "No such namespace: never-used-ns-example"))))
+
+    (testing "non-existing Var"
+      (let [response (session/message {:op :eval
+                                       :code "nil"
+                                       :pprint "true"
+                                       :pprint-fn "clojure.core/never-used-pprint-example"})]
+        (is (= (:status response) #{"eval-error" "done"}))
+        (is (= (:ex response) "class clojure.lang.ExceptionInfo"))
+        (is (= (:root-ex response) "class java.lang.IllegalArgumentException"))
+        (is (.startsWith (:err response) "Error printing return value (IllegalArgumentException) at cider.nrepl.middleware.pprint/resolve-pprint-fn"))
+        (is (.contains (:err response) "clojure.core/never-used-pprint-example is not resolvable to a var"))))
+
+    (testing "nil input"
+      (let [response (session/message {:op :eval
+                                       :code "nil"
+                                       :pprint "true"
+                                       :pprint-fn nil})]
+        (is (= (:status response) #{"eval-error" "done"}))
+        (is (= (:ex response) "class clojure.lang.ExceptionInfo"))
+        (is (= (:root-ex response) "class java.lang.NullPointerException"))
+        (is (.startsWith (:err response) "Error printing return value (NullPointerException) at clojure.lang.Var/find"))))))

test/clj/cider/nrepl/middleware/stacktrace_test.clj

@@ -121,8 +121,15 @@
                                                                              (binding [*print-level* 3]
                                                                                (clojure.pprint/pprint object))))))))
   (testing "compilation errors"
-    (is (re-find #"Unable to resolve symbol: not-defined in this context"
-                 (:message (first causes3))))))
+    (let [clojure-version ((juxt :major :minor) *clojure-version*)]
+      (if (< (compare clojure-version [1 10]) 0)
+        ;; 1.8 / 1.9
+        (is (re-find #"Unable to resolve symbol: not-defined in this context"
+                     (:message (first causes3))))
+
+        ;; 1.10+
+        (is (re-find #"Syntax error compiling at \(cider/nrepl/middleware/stacktrace_test\.clj:"
+                     (:message (first causes3))))))))
 
 (deftest compilation-errors-test
   (testing "extract-location"