Support clj-reload workflow

Fix clojure-emacs#849

doc/modules/ROOT/pages/nrepl-api/ops.adoc

@@ -1777,3 +1777,40 @@ Returns::
 * `:status` done
 * `:cider/log-update-consumer` The consumer that was updated.
 
+
+
+=== `cider.clj-reload/reload`
+
+Reloads all changed files in dependency order,
+using the io.github.tonsky/clj-reload library. It is bundled with cider-nrepl.
+If that dependency is already in present your project and clj-reload.core/init has been invoked beforehand,
+those configured directories will be honored.
+
+Required parameters::
+{blank}
+
+Optional parameters::
+{blank}
+
+Returns::
+* `:error` A sequence of all causes of the thrown exception when ``status`` is ``:error``.
+* `:progress` Description of current namespace being unloaded/loaded.
+* `:status` ``:ok`` if reloading was successful; otherwise ``:error``.
+
+
+
+=== `cider.clj-reload/reload-all`
+
+Reloads all files in dependency order.
+
+Required parameters::
+{blank}
+
+Optional parameters::
+{blank}
+
+Returns::
+* `:error` A sequence of all causes of the thrown exception when ``status`` is ``:error``.
+* `:reloading` Description of current namespace being unloaded/loaded.
+* `:status` ``:ok`` if reloading was successful; otherwise ``:error``.
+

doc/modules/ROOT/pages/usage.adoc

@@ -47,6 +47,7 @@ under `:repl-options`.
                   cider.nrepl/wrap-spec
                   cider.nrepl/wrap-profile
                   cider.nrepl/wrap-refresh
+                  cider.nrepl/wrap-reload
                   cider.nrepl/wrap-resource
                   cider.nrepl/wrap-stacktrace
                   cider.nrepl/wrap-test
@@ -161,6 +162,7 @@ That's how CIDER's nREPL handler is created:
     cider.nrepl/wrap-slurp
     cider.nrepl/wrap-profile
     cider.nrepl/wrap-refresh
+    cider.nrepl/wrap-reload
     cider.nrepl/wrap-resource
     cider.nrepl/wrap-spec
     cider.nrepl/wrap-stacktrace

project.clj

@@ -19,6 +19,7 @@
                  ~(with-meta '[org.clojure/tools.namespace "1.3.0"]
                     ;; :cognitest uses tools.namespace, so we cannot inline it while running tests.
                     {:inline-dep (not= "true" (System/getenv "SKIP_INLINING_TEST_DEPS"))})
+                 ^:inline-dep [io.github.tonsky/clj-reload "0.2.0"]
                  ^:inline-dep [org.clojure/tools.trace "0.7.11"]
                  ^:inline-dep [org.clojure/tools.reader "1.3.6"]
                  [mx.cider/logjam "0.2.0"]]
@@ -157,6 +158,7 @@
                                                               cider.nrepl/wrap-out
                                                               cider.nrepl/wrap-profile
                                                               cider.nrepl/wrap-refresh
+                                                              cider.nrepl/wrap-reload
                                                               cider.nrepl/wrap-resource
                                                               cider.nrepl/wrap-slurp
                                                               cider.nrepl/wrap-spec

src/cider/nrepl.clj

@@ -632,6 +632,23 @@ if applicable, and re-render the updated value."
              "refresh-clear"
              {:doc "Clears the state of the refresh middleware. This can help recover from a failed load or a circular dependency error."}}})
 
+(def-wrapper wrap-reload cider.nrepl.middleware.reload/handle-reload
+  {:doc "Reload middleware."
+   :requires #{"clone" #'wrap-print}
+   :handles {"cider.clj-reload/reload"
+             {:doc "Reloads all changed files in dependency order,
+using the io.github.tonsky/clj-reload library. It is bundled with cider-nrepl.
+If that dependency is already in present your project and clj-reload.core/init has been invoked beforehand,
+those configured directories will be honored."
+              :returns {"progress" "Description of current namespace being unloaded/loaded."
+                        "status" "`:ok` if reloading was successful; otherwise `:error`."
+                        "error" "A sequence of all causes of the thrown exception when `status` is `:error`."}}
+             "cider.clj-reload/reload-all"
+             {:doc "Reloads all files in dependency order."
+              :returns {"reloading" "Description of current namespace being unloaded/loaded."
+                        "status" "`:ok` if reloading was successful; otherwise `:error`."
+                        "error" "A sequence of all causes of the thrown exception when `status` is `:error`."}}}})
+
 (def-wrapper wrap-resource cider.nrepl.middleware.resource/handle-resource
   {:doc "Middleware that provides the path to resource."
    :handles {"resource"

src/cider/nrepl/middleware.clj

@@ -23,6 +23,7 @@
     cider.nrepl/wrap-slurp
     cider.nrepl/wrap-profile
     cider.nrepl/wrap-refresh
+    cider.nrepl/wrap-reload
     cider.nrepl/wrap-resource
     cider.nrepl/wrap-spec
     cider.nrepl/wrap-stacktrace

src/cider/nrepl/middleware/reload.clj

@@ -0,0 +1,50 @@
+(ns cider.nrepl.middleware.reload
+  (:require
+   [clj-reload.core :as reload]
+   [clojure.main :refer [repl-caught]]
+   [clojure.string :as str]
+   [haystack.analyzer :as analyzer]
+   [nrepl.middleware.interruptible-eval :refer [*msg*]]
+   [nrepl.middleware.print :as print]
+   [nrepl.misc :refer [response-for]]
+   [nrepl.transport :as transport]
+   [orchard.misc :as misc]))
+
+(defn- user-reload
+  "clj-reload.core/reload from the user project.
+  Must be configured via clj-reload.core/init before being called."
+  []
+  (some-> (symbol "clj-reload.core" "reload") ;; Don't use mrandorsenized version
+          resolve))
+
+(defn respond
+  [{:keys [transport] :as msg} response]
+  (transport/send transport (response-for msg response)))
+
+(defn- refresh-reply
+  [{:keys [::print/print-fn transport session id] :as msg}]
+  (let [{:keys [exec]} (meta session)]
+    (exec id
+          (fn []
+            (try
+              (let [reload (or (user-reload) reload/reload)]
+                (reload (cond-> {:log-fn (fn [& args]
+                                           (respond msg {:progress (str/join " " args)}))}
+                          (:all msg) (assoc :only :all)))
+                (respond msg {:status :ok}))
+              (catch Throwable error
+                (respond msg {:status :error
+                              ;; TODO assoc :file, :line info if available
+                              :error  (analyzer/analyze error print-fn)})
+                (binding [*msg* msg
+                          *err* (print/replying-PrintWriter :err msg {})]
+                  (repl-caught error)))))
+
+          (fn [] (respond msg {:status :done})))))
+
+(defn handle-reload [handler msg]
+  (case (:op msg)
+    "cider.clj-reload/reload" (refresh-reply msg)
+    "cider.clj-reload/reload-all" (refresh-reply (assoc msg :all true))
+    (handler msg)))
+

test/clj/cider/nrepl/middleware/reload_test.clj

@@ -0,0 +1,36 @@
+(ns cider.nrepl.middleware.reload-test
+  (:require
+   [cider.nrepl.middleware.reload :as rl]
+   [cider.nrepl.test-session :as session]
+   [clj-reload.core :as reload]
+   [clojure.test :refer :all]))
+
+(use-fixtures :each session/session-fixture)
+
+(def ^:private dirs-to-reload
+  ;; Limit the scope of what we reload, because (for example) reloading the
+  ;; cider.nrepl.middleware.test-session ns causes *session* in that ns to be
+  ;; unloaded, which breaks session-fixture, and hence all of the below tests.
+  ["test/clj/cider/nrepl/middleware/util"])
+
+(reload/init {:dirs dirs-to-reload})
+
+(deftest user-reload
+  (testing "returns nil if clojure.tools.namespace isn't loaded"
+    (with-redefs [resolve (constantly nil)]
+      (is (nil? (#'rl/user-reload))))))
+
+(deftest reload-op-test
+  (testing "reload op works"
+    (let [response (session/message {:op "cider.clj-reload/reload"})]
+      ;; There is nothing to reload since the files did not change,
+      ;; but the message does come from clj-reload.core/reload.
+      (is (= "Nothing to reload" (:progress response)))
+      (is (= #{"done" "ok"} (:status response))))))
+
+(deftest reload-all-op-test
+  (testing "reload-all op works"
+    (let [response (session/message {:op "cider.clj-reload/reload-all"})]
+      (is (seq (:progress response)))
+      (is (= #{"done" "ok"} (:status response))))))
+