Close #391: improve defalias error msg

src/cljc/schema/core.cljc

@@ -685,9 +685,9 @@
   "Support for (mutually) recursive schemas by passing a var that points to a schema,
    e.g (recursive #'ExampleRecursiveSchema)."
   [schema]
-  (when-not #?(:clj (instance? clojure.lang.IDeref schema)
-               :cljs (satisfies? IDeref schema))
-    (macros/error! (utils/format* "Not an IDeref: %s" schema)))
+  (macros/assert! #?(:clj (instance? clojure.lang.IDeref schema)
+                     :cljs (satisfies? IDeref schema))
+                  "Not an IDeref: %s" schema)
   (Recursive. schema))
 
 
@@ -1134,6 +1134,9 @@
 (clojure.core/defn schema-with-name
   "Records name in schema's metadata."
   [schema name]
+  (macros/assert! #?(:clj (instance? clojure.lang.IObj schema)
+                     :cljs (satisfies? IWithMeta schema))
+                  "Named schema (such as the right-most `s/defalias` arg) must support metadata: %s" (utils/type-of schema))
   (vary-meta schema assoc :name name))
 
 (clojure.core/defn schema-name

test/clj/schema/test_macros.clj

@@ -24,3 +24,11 @@
   [f & args]
   (when (sm/compile-fn-validation? &env f)
     `(~'is (~'thrown? ~'Throwable (~f ~@args)))))
+
+(defmacro is-assert!
+  "Assert that an assert! is thrown with msg"
+  [form expected-msg]
+  `(~'is (~'thrown-with-msg?
+           ~(if (sm/cljs-env? &env) 'js/Error 'java.lang.RuntimeException)
+           ~expected-msg
+           ~form)))

test/cljc/schema/core_test.cljc

@@ -7,10 +7,10 @@
       - The optional last argument also checks the printed Clojure representation of the error.
     - (invalid-call! s x) asserts that calling the function throws an error."
   (:refer-clojure :exclude [parse-long])
-  #?(:clj (:use clojure.test [schema.test-macros :only [valid! invalid! invalid-call!]]))
+  #?(:clj (:use clojure.test [schema.test-macros :only [valid! invalid! invalid-call! is-assert!]]))
   #?(:cljs (:use-macros
              [cljs.test :only [is deftest testing are]]
-             [schema.test-macros :only [valid! invalid! invalid-call!]]))
+             [schema.test-macros :only [valid! invalid! invalid-call! is-assert!]]))
   #?(:cljs (:require-macros [schema.macros :as macros]))
   (:require
    [clojure.string :as str]
@@ -421,7 +421,8 @@
       #?(:cljs (is (= '(recursive ...) (val explanation))))))
 
   (is (= '{:black {(optional-key :red) (recursive (var schema.core-test/TestBlackNode))}}
-         (s/explain TestBlackNode))))
+         (s/explain TestBlackNode)))
+  (is-assert! (s/recursive nil) #"Not an IDeref: null"))
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -1517,7 +1518,11 @@
     (valid! schema {:baz 123})
     (invalid! schema {:baz "abc"})
     (is (= 'Baz (s/schema-name schema)))
-    (is (=  nil (s/schema-ns schema)))))
+    (is (= nil (s/schema-ns schema))))
+  #?(:clj (is-assert! (s/schema-with-name s/Str 'Baz)
+                      #"Named schema \(such as the right-most `s/defalias` arg\) must support metadata: class java.lang.Class")
+     :cljs (is-assert! (s/schema-with-name nil 'Baz)
+                       #"Named schema \(such as the right-most `s/defalias` arg\) must support metadata: object")))
 
 (deftest schema-name-test
   (is (= 'TestFoo (s/schema-name TestFoo))))