propagate useful metadata to protocol fns #349

- also add :added metadata for fns with newly visible docstrings

Signed-off-by: Stuart Halloway <stu@thinkrelevance.com>

4 files changed, 25 insertions, 14 deletions

diff --git a/src/clj/clojure/core_deftype.clj b/src/clj/clojure/core_deftype.clj
index 161514db..4ca47637 100644
--- a/src/clj/clojure/core_deftype.clj
+++ b/src/clj/clojure/core_deftype.clj
@@ -525,7 +525,8 @@
             keyword? (recur (assoc opts (first sigs) (second sigs)) (nnext sigs))
             [opts sigs]))
         sigs (reduce (fn [m s]
-                       (let [mname (with-meta (first s) nil)
+                       (let [name-meta (meta (first s))
+                             mname (with-meta (first s) nil)
                              [arglists doc]
                                (loop [as [] rs (rest s)]
                                  (if (vector? (first rs))
@@ -533,10 +534,11 @@
                                    [(seq as) (first rs)]))]
                          (when (some #{0} (map count arglists))
                            (throw (IllegalArgumentException. (str "Protocol fn: " mname " must take at least one arg"))))
-                         (assoc m (keyword mname)  
-                                {:name (vary-meta mname assoc :doc doc :arglists arglists)
-                                 :arglists arglists
-                                 :doc doc})))
+                         (assoc m (keyword mname)
+                                (merge name-meta
+                                       {:name (vary-meta mname assoc :doc doc :arglists arglists)
+                                        :arglists arglists
+                                        :doc doc}))))
                      {} sigs)
         meths (mapcat (fn [sig]
                         (let [m (munge (:name sig))]
@@ -562,8 +564,8 @@
                        :method-builders 
                         ~(apply hash-map 
                                 (mapcat 
-                                 (fn [s] 
-                                   [`(intern *ns* (with-meta '~(:name s) {:protocol (var ~name)}))
+                                 (fn [s]
+                                   [`(intern *ns* (with-meta '~(:name s) (merge '~s {:protocol (var ~name)})))
                                     (emit-method-builder (:on-interface opts) (:name s) (:on s) (:arglists s))])
                                  (vals sigs)))))
      (-reset-methods ~name)
diff --git a/src/clj/clojure/java/io.clj b/src/clj/clojure/java/io.clj
index 97ae4e3e..4d6c551f 100644
--- a/src/clj/clojure/java/io.clj
+++ b/src/clj/clojure/java/io.clj
@@ -33,8 +33,8 @@
 
 (defprotocol ^{:added "1.2"} Coercions
   "Coerce between various 'resource-namish' things."
-  (^File as-file [x] "Coerce argument to a file.")
-  (^URL as-url [x] "Coerce argument to a URL."))
+  (^{:tag File, :added "1.2"} as-file [x] "Coerce argument to a file.")
+  (^{:tag URL, :added "1.2"} as-url [x] "Coerce argument to a URL."))
 
 (extend-protocol Coercions
   nil
@@ -72,10 +72,10 @@
 
    Callers should generally prefer the higher level API provided by
    reader, writer, input-stream, and output-stream."
-  (make-reader [x opts] "Creates a BufferedReader. See also IOFactory docs.")
-  (make-writer [x opts] "Creates a BufferedWriter. See also IOFactory docs.")
-  (make-input-stream [x opts] "Creates a BufferedInputStream. See also IOFactory docs.")
-  (make-output-stream [x opts] "Creates a BufferedOutputStream. See also IOFactory docs."))
+  (^{:added "1.2"} make-reader [x opts] "Creates a BufferedReader. See also IOFactory docs.")
+  (^{:added "1.2"} make-writer [x opts] "Creates a BufferedWriter. See also IOFactory docs.")
+  (^{:added "1.2"} make-input-stream [x opts] "Creates a BufferedInputStream. See also IOFactory docs.")
+  (^{:added "1.2"} make-output-stream [x opts] "Creates a BufferedOutputStream. See also IOFactory docs."))
 
 (defn ^Reader reader
   "Attempts to coerce its argument into an open java.io.Reader.
diff --git a/test/clojure/test_clojure/protocols.clj b/test/clojure/test_clojure/protocols.clj
index 90de0010..52aa346f 100644
--- a/test/clojure/test_clojure/protocols.clj
+++ b/test/clojure/test_clojure/protocols.clj
@@ -66,6 +66,15 @@
   (getValue [_] v))
 
 (deftest protocols-test
+  (testing "protocol fns have useful metadata"
+    (let [common-meta {:ns (find-ns 'clojure.test-clojure.protocols.examples)
+                       :protocol #'ExampleProtocol}]
+      (are [m f] (= (merge (quote m) common-meta)
+                    (meta (var f)))
+           {:name foo :arglists ([a]) :doc "method with one arg"} foo
+           {:name bar :arglists ([a b]) :doc "method with two args"} bar
+           {:name baz :arglists ([a] [a b]) :doc "method with multiple arities" :tag String} baz
+           {:name with-quux :arglists ([a]) :doc "method name with a hyphen"} with-quux)))
   (testing "protocol fns throw IllegalArgumentException if no impl matches"
     (is (thrown-with-msg?
           IllegalArgumentException
diff --git a/test/clojure/test_clojure/protocols/examples.clj b/test/clojure/test_clojure/protocols/examples.clj
index 877559d0..b9644750 100644
--- a/test/clojure/test_clojure/protocols/examples.clj
+++ b/test/clojure/test_clojure/protocols/examples.clj
@@ -5,7 +5,7 @@
 
   (foo [a] "method with one arg")
   (bar [a b] "method with two args")
-  (baz [a] [a b] "method with multiple arities")
+  (^String baz [a] [a b] "method with multiple arities")
   (with-quux [a] "method name with a hyphen"))
 
 (definterface ExampleInterface