Inject cider REPL dependencies at cider-jack-in

So users don't have to fiddle with profiles.clj and the like, see
details in clojure-emacs#1531 Supports both leiningen and boot. Additionally there is
a defcustom `cider-inject-dependencies-at-jack-in` to control this
functionality (defaults to t); and an extension point
(`cider-add-repl-dependencies`) so other tools like clj-refactor
can inject to their own dependencies, middlewares.

Fix clojure-emacs#1531 and clojure-emacs#1534

CHANGELOG.md

@@ -22,6 +22,7 @@ and try to associate the created connection with this project automatically.
 
 ### Changes
 
+* [#1531](https://github.com/clojure-emacs/cider/issues/1531) `cider-jack-in` now injects its own dependencies using CLI. Both leiningen and boot are supported. Set `cider-inject-dependencies-at-jack-in` to nil to opt out. Extension point for other tools to inject their own dependencies is `cider-add-repl-dependencies`.
 * `cider-inspect` now operates by default on the last sexp. Its behavior can be altered via prefix arguments.
 * Requires Clojure(Script) 1.7 or newer.
 * Requires Java 7 or newer.

README.md

@@ -218,12 +218,20 @@ Stable by adding this to your Emacs initialization:
   [GNU ELPA repository](https://elpa.gnu.org/). It's the only package repository
   enabled by default in Emacs and you should not disable it!**
 
-### Setting up CIDER's nREPL middleware
+### CIDER's nREPL middleware
 
 Much of CIDER's functionality depends on the presence of CIDER's own
-[nREPL middleware][cider-nrepl].
+[nREPL middleware][cider-nrepl]. When `cider-jack-in` (<kbd>C-c M-j</kbd>) is used CIDER modifies the CLI starting up the REPL to inject its own dependencies. Both Leiningen and Boot powered projects are supported.
 
-#### Using Leiningen
+**`profiles.clj` or `profile.boot` don't need to be modified anymore for the above usecase!**
+
+If this behaviour is not preferred set `cider-inject-dependencies-at-jack-in` to nil. At `cider-jack-in` the CLI command is always shown in the minibuffer (or see it in the `*Messages*` buffer).
+
+If a standalone REPL is preferred and `cider-connect` is used adding the middlewares are still needed as CIDER can not control dependencies of an independent REPL.
+
+#### When setting up a standalone REPL
+
+##### Using Leiningen #####
 
 Use the convenient plugin for defaults, either in your project's
 `project.clj` file or in the :repl profile in `~/.lein/profiles.clj`.
@@ -242,7 +250,7 @@ A minimal `profiles.clj` for CIDER would be:
 middleware will always get loaded, causing `lein` to start slower.  You really
 need it just for `lein repl` and this is what the `:repl` profile is for.**
 
-#### Using Boot
+##### Using Boot #####
 
 Boot users can configure the tool to include the middleware automatically in
 all of their projects using a `~/.boot/profile.boot` file like so:

cider.el

@@ -165,6 +165,11 @@ This variable is used by `cider-connect'."
   :type 'boolean
   :version "0.9.0")
 
+(defcustom cider-inject-dependencies-at-jack-in t
+  "When nil, do not inject repl dependencies (most likely nrepl middlewares) at jack in time."
+  :type 'boolean
+  :version "0.11.0")
+
 (defvar cider-ps-running-nrepls-command "ps u | grep leiningen"
   "Process snapshot command used in `cider-locate-running-nrepl-ports'.")
 
@@ -177,6 +182,15 @@ Sub-match 1 must be the project path.")
 (defvar cider-host-history nil
   "Completion history for connection hosts.")
 
+(defvar cider-repl-dependencies
+  `((("org.clojure/tools.nrepl" "0.2.12"))
+    (("cider/cider-nrepl" ,(upcase cider-version)))
+    ("cider.nrepl/cider-middleware"))
+  "List of Clojure artifacts for starting the REPL.
+First item is a list of dependencies where elements are lists of artifact name and version.
+Second item is a list of leiningen plugins where elements are lists of artifact name and version.
+Third item is a list of nrepl middleware names.")
+
 ;;;###autoload
 (defun cider-version ()
   "Display CIDER's version."
@@ -204,6 +218,70 @@ Sub-match 1 must be the project path.")
     ("boot" cider-boot-parameters)
     ("gradle" cider-gradle-parameters)))
 
+(defun boot-command-prefix (dependencies)
+  (concat
+   (mapconcat
+    'identity
+    (seq-map (lambda (dep) (format "-d %s:%s" (car dep) (cadr dep))) dependencies)
+    " ")
+   " "))
+
+(defun boot-repl-task-params (params middlewares)
+  (replace-regexp-in-string
+   "repl"
+   (concat
+    "repl "
+    (mapconcat
+     'identity
+     (seq-map (lambda (middleware) (format "-m %s" middleware)) middlewares)
+     " "))
+   params))
+
+(defun cider-boot-jack-in-dependencies (params repl-deps)
+  (concat
+   (boot-command-prefix
+    (seq-concatenate 'list
+                     (car repl-deps)
+                     (cadr repl-deps)))
+   (boot-repl-task-params params (car (last repl-deps)))))
+
+(defun cider-lein-jack-in-dependencies (params repl-deps)
+  (concat
+   (mapconcat
+    'identity
+    (seq-concatenate
+     'list
+     (seq-map (lambda (dep) (format "update-in :dependencies conj \"[%s \\\"%s\\\"]\"" (car dep) (cadr dep))) (car repl-deps))
+     (seq-map (lambda (plugin) (format "update-in :plugins conj \"[%s \\\"%s\\\"]\"" (car plugin) (cadr plugin))) (cadr repl-deps)))
+    " -- ")
+   " -- "
+   params))
+
+(defun cider-add-repl-dependencies (dependencies lein-plugins middlewares)
+  "Extension point to add REPL dependencies to `cider-repl-dependencies' so they are injected from the CLI at cider jack in."
+  (let ((orig-deps (car cider-repl-dependencies))
+        (orig-plugins (cadr cider-repl-dependencies))
+        (orig-middlewares (car (last cider-repl-dependencies))))
+    (setq
+     cider-repl-dependencies
+     `(,(if (not dependencies)
+            orig-deps
+          (seq-concatenate 'list orig-deps dependencies))
+       ,(if (not lein-plugins)
+            orig-plugins
+          (seq-concatenate 'list orig-plugins lein-plugins))
+       ,(if (not middlewares)
+            orig-middlewares
+          (seq-concatenate 'list orig-middlewares middlewares))))))
+
+(defun cider-jack-in-dependencies (params project-type)
+  "Modify the params so that REPL dependencies as set in `cider-repl-dependencies' are injected from the CLI according to the used `project-type'.
+Eliminates the need for hacking profiles.clj or the boot script for supporting cider with its nrepl middleware."
+  (pcase project-type
+    ("lein" (cider-lein-jack-in-dependencies params cider-repl-dependencies))
+    ("boot" (cider-boot-jack-in-dependencies params cider-repl-dependencies))
+    ("gradle" "")))
+
 (defcustom cider-cljs-lein-repl "(cemerick.piggieback/cljs-repl (cljs.repl.rhino/repl-env))"
   "Clojure form that returns a ClojureScript REPL environment.
 This is only used in lein projects.  It is evaluated in a Clojure REPL and
@@ -298,6 +376,10 @@ own buffer."
                                                 (cider-jack-in-params project-type))
                                         (cider-jack-in-params project-type))
                          (cider-jack-in-params project-type)))
+               (params (if cider-inject-dependencies-at-jack-in
+                           (cider-jack-in-dependencies params project-type)
+                         params))
+
                (cmd (format "%s %s" (cider-jack-in-command project-type) params)))
           (when-let ((repl-buff (cider-find-reusable-repl-buffer nil project-dir)))
             (let ((nrepl-create-client-buffer-function  #'cider-repl-create)