Reduce output for dependency resolution

Showing every failed repo lookup is bad for users.
They see the failure and get confused.

Hook up a custom listener that has the following behavior:

1. success -> print out artifact name, size, and repository name
2. failure -> ignore unless it is the last repo, then print out failure
   message with artifact name.

Fixes #610.

leiningen-core/src/leiningen/core/classpath.clj

@@ -118,7 +118,27 @@
                         (map (partial update-policies update checksum)))
      :coordinates (get project dependencies-key)
      :mirrors mirrors
-     :transfer-listener :stdout
+     :transfer-listener
+     (bound-fn [e]
+       (let [{:keys [type resource error]} e]
+         (let [{:keys [repository name size]} resource]
+           (case type
+             :started
+             (println "Retrieving"
+                      name
+                      (if (neg? size)
+                        ""
+                        (format "(%sk)"
+                                (Math/round (double (max 1 (/ size 1024))))))
+                      "from"
+                      (or (first (first (filter #(= repository (:url (second %)))
+                                                repositories)))
+                          repository))
+             :failed
+             (if (and (= repository (:url (second (last repositories))))
+                      error)
+               (println "Failed to find" name))
+             nil))))
      :proxy (get-proxy-settings))
     (catch DependencyResolutionException e
       (binding [*out* *err*]

leiningen-core/src/leiningen/core/project.clj

@@ -39,7 +39,7 @@
                :compile-path "target/classes"
                :target-path "target"
                :prep-tasks ["javac" "compile"]
-               :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+               :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                               ;; TODO: point to releases-only before 2.0 is out
                               ["clojars" {:url "https://clojars.org/repo/"}]]
                :deploy-repositories [["clojars" {:url "https://clojars.org/repo/"

leiningen-core/test/leiningen/core/test/project.clj

@@ -35,7 +35,7 @@
                                [stencil "0.2.0"]],
                :twelve 12 ; testing unquote
 
-               :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+               :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                               ["clojars" {:url "https://clojars.org/repo/"}]]})
 
 (deftest test-read-project
@@ -160,7 +160,7 @@
 (deftest test-merge-anon-profiles
   (let [expected-result {:A 1 :C 3 :profiles {:a {:A 1}
                                               :b {:B 2}}
-                         :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+                         :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                                         ["clojars" {:url "https://clojars.org/repo/"}]]
                          :dependencies [], :compile-path "classes"}]
     (is (= expected-result
@@ -169,7 +169,7 @@
 
 (deftest test-composite-profiles
   (let [expected-result {:A '(2 3 1), :B 2, :C 3,
-                         :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+                         :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                                         ["clojars" {:url "https://clojars.org/repo/"}]]
                          :dependencies [], :compile-path "classes"}]
     (is (= expected-result
@@ -182,7 +182,7 @@
 
 (deftest test-override-default
   (let [expected-result {:A 1, :B 2, :C 3
-                         :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+                         :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                                         ["clojars" {:url "https://clojars.org/repo/"}]]
                          :dependencies [], :compile-path "classes"}]
     (is (= expected-result
@@ -197,7 +197,7 @@
   (let [expected-result {:A 1 :C 3 :profiles {:a {:A 1}
                                               :b {:B 2}
                                               :c {:C 3}}
-                         :repositories [["central" {:url "http://repo1.maven.org/maven2"}]
+                         :repositories [["central" {:url "http://repo1.maven.org/maven2/"}]
                                         ["clojars" {:url "https://clojars.org/repo/"}]]
                          :dependencies [], :compile-path "classes"}]
     (is (= expected-result

test/leiningen/test/pom.clj

@@ -68,7 +68,7 @@
            (map #(first-in % [:repository :id])
                 (deep-content xml [:project :repositories])))
         "repositories are named")
-    (is (= ["http://repo1.maven.org/maven2" "https://clojars.org/repo/"
+    (is (= ["http://repo1.maven.org/maven2/" "https://clojars.org/repo/"
             "http://example.com/repo"]
            (map #(first-in % [:repository :url])
                 (deep-content xml [:project :repositories])))