From cb923eadcc33a3667db0d3d5d2876dfbb4d482ae Mon Sep 17 00:00:00 2001
From: Henrik Lissner <henrik@lissner.net>
Date: Thu, 21 Feb 2019 16:08:27 -0500
Subject: [PATCH] Add basic LSP support

Still needs to be documented, but includes support for the following
languages:

+ C/C++/ObjC
+ Go
+ Java
+ Javascript
+ OCaml
+ PHP
+ Python
+ Ruby
+ Scala
+ Swift
+ HTML/CSS

Relevant to #460, #716, #1186
---
 init.example.el                     |  1 +
 modules/lang/cc/config.el           | 23 ++++++++++++++++--
 modules/lang/cc/packages.el         | 29 +++++++++++------------
 modules/lang/go/config.el           |  7 ++++--
 modules/lang/java/+lsp.el           | 10 ++++++++
 modules/lang/java/config.el         |  3 ++-
 modules/lang/java/packages.el       |  2 ++
 modules/lang/javascript/config.el   |  5 ++++
 modules/lang/javascript/packages.el | 14 +++++++----
 modules/lang/ocaml/config.el        | 36 +++++++++++++++--------------
 modules/lang/php/config.el          |  9 +++++---
 modules/lang/php/packages.el        |  3 ++-
 modules/lang/python/config.el       |  4 ++++
 modules/lang/python/packages.el     |  3 ++-
 modules/lang/ruby/config.el         |  4 ++++
 modules/lang/rust/config.el         |  5 +++-
 modules/lang/scala/config.el        | 11 ++++++++-
 modules/lang/scala/packages.el      |  5 +++-
 modules/lang/swift/config.el        | 11 +++++++--
 modules/lang/swift/packages.el      | 11 +++++----
 modules/lang/web/+css.el            |  4 ++++
 modules/lang/web/+html.el           |  4 ++++
 modules/tools/lsp/autoload.el       |  7 ++++++
 modules/tools/lsp/config.el         | 21 +++++++++++++++++
 modules/tools/lsp/packages.el       |  7 ++++++
 25 files changed, 182 insertions(+), 57 deletions(-)
 create mode 100644 modules/lang/java/+lsp.el
 create mode 100644 modules/tools/lsp/autoload.el
 create mode 100644 modules/tools/lsp/config.el
 create mode 100644 modules/tools/lsp/packages.el

diff --git a/init.example.el b/init.example.el
index c72d6b6e1..65c7cc9b8 100644
--- a/init.example.el
+++ b/init.example.el
@@ -67,6 +67,7 @@
        ;;editorconfig      ; let someone else argue about tabs vs spaces
        ;;ein               ; tame Jupyter notebooks with emacs
        ;;gist              ; interacting with github gists
+       ;;lsp
        ;;macos             ; MacOS-specific commands
        ;;magit             ; a git porcelain for Emacs
        ;;make              ; run make tasks from Emacs
diff --git a/modules/lang/cc/config.el b/modules/lang/cc/config.el
index 9d5fe1b19..53488b288 100644
--- a/modules/lang/cc/config.el
+++ b/modules/lang/cc/config.el
@@ -125,7 +125,7 @@ compilation database is present in the project.")
 
 
 (def-package! irony
-  :when (featurep! +irony)
+  :unless (featurep! +lsp)
   :commands (irony-install-server irony-mode)
   :preface
   (setq irony-server-install-prefix (concat doom-etc-dir "irony-server/"))
@@ -181,7 +181,7 @@ compilation database is present in the project.")
 ;; Rtags Support
 
 (def-package! rtags
-  :when (featurep! +rtags)
+  :unless (featurep! +lsp)
   :commands rtags-executable-find
   :preface
   (setq rtags-install-path (concat doom-etc-dir "rtags/"))
@@ -219,3 +219,22 @@ compilation database is present in the project.")
   (when (featurep 'evil)
     (add-hook 'rtags-jump-hook #'evil-set-jump))
   (add-hook 'rtags-after-find-file-hook #'recenter))
+
+
+;;
+;; LSP
+
+(def-package! cquery
+  :when (featurep! +lsp)
+  :hook ((c-mode c++-mode objc-mode) . +lsp|init-cquery)
+  :config
+  (defun +lsp|init-cquery ()
+    (setq-local company-transformers nil)
+    (setq-local company-lsp-cache-candidates nil)
+    (condition-case nil
+        (lsp)
+      (user-error nil)))
+  (setq cquery-extra-init-params
+        '(:index (:comments 2)
+                 :cacheFormat "msgpack"
+                 :completion (:detailedLabel t))))
diff --git a/modules/lang/cc/packages.el b/modules/lang/cc/packages.el
index 776b58a3c..cdb6d85d5 100644
--- a/modules/lang/cc/packages.el
+++ b/modules/lang/cc/packages.el
@@ -12,18 +12,17 @@
   (when (featurep! :completion company)
     (package! company-glsl :recipe (:fetcher github :repo "Kaali/company-glsl"))))
 
-(when (featurep! +irony)
-  (package! irony)
-  (package! irony-eldoc)
-  (when (featurep! :feature syntax-checker)
-    (package! flycheck-irony))
-  (when (featurep! :completion company)
-    (package! company-irony)
-    (package! company-irony-c-headers)))
-
-(when (featurep! +rtags)
-  (package! rtags)
-  (when (featurep! :completion ivy)
-    (package! ivy-rtags))
-  (when (featurep! :completion helm)
-    (package! helm-rtags)))
+(if (featurep! +lsp)
+    (package! cquery)
+  (when (package! irony)
+    (package! irony-eldoc)
+    (when (featurep! :feature syntax-checker)
+      (package! flycheck-irony))
+    (when (featurep! :completion company)
+      (package! company-irony)
+      (package! company-irony-c-headers)))
+  (when (package! rtags)
+    (when (featurep! :completion ivy)
+      (package! ivy-rtags))
+    (when (featurep! :completion helm)
+      (package! helm-rtags))))
diff --git a/modules/lang/go/config.el b/modules/lang/go/config.el
index 6bde94e93..0952be4e8 100644
--- a/modules/lang/go/config.el
+++ b/modules/lang/go/config.el
@@ -20,7 +20,9 @@
                 "gofmt"
               "goimports"))))
 
-  (add-hook 'go-mode-hook #'go-eldoc-setup)
+  (if (featurep! +lsp)
+      (add-hook 'go-mode-hook #'+lsp|init)
+    (add-hook 'go-mode-hook #'go-eldoc-setup))
 
   (map! :map go-mode-map
         :localleader
@@ -57,7 +59,8 @@
 
 
 (def-package! company-go
-  :when (featurep! :completion company)
+  :when (and (featurep! :completion company)
+             (not (featurep! +lsp)))
   :after go-mode
   :config
   (set-company-backend! 'go-mode 'company-go)
diff --git a/modules/lang/java/+lsp.el b/modules/lang/java/+lsp.el
new file mode 100644
index 000000000..88898614d
--- /dev/null
+++ b/modules/lang/java/+lsp.el
@@ -0,0 +1,10 @@
+;;; lang/java/+lsp.el -*- lexical-binding: t; -*-
+;;;###if (featurep! +lsp)
+
+(def-package! lsp-java
+  :after-call java-mode
+  :init (add-hook 'java-mode-hook #'+lsp|init)
+  :config
+  ;; TODO keybinds
+  ;; TODO treemacs integration (?)
+  )
diff --git a/modules/lang/java/config.el b/modules/lang/java/config.el
index 5e1e07d5b..955651aaf 100644
--- a/modules/lang/java/config.el
+++ b/modules/lang/java/config.el
@@ -23,7 +23,8 @@ If the depth is 2, the first two directories are removed: net.lissner.game.")
 
 (add-hook 'java-mode-hook #'rainbow-delimiters-mode)
 
-(cond ((featurep! +meghanada) (load! "+meghanada"))
+(cond ((featurep! +lsp) (load! "+lsp"))
+      ((featurep! +meghanada) (load! "+meghanada"))
       ;; TODO lang/java +lsp (lsp-java?)
       ;; ((featurep! +lsp) (load! "+lsp"))
       )
diff --git a/modules/lang/java/packages.el b/modules/lang/java/packages.el
index 03deb4911..c9a0014a2 100644
--- a/modules/lang/java/packages.el
+++ b/modules/lang/java/packages.el
@@ -12,3 +12,5 @@
   (when (featurep! :completion company)
     (package! company-emacs-eclim)))
 
+(when (featurep! +lsp)
+  (package! lsp-java))
diff --git a/modules/lang/javascript/config.el b/modules/lang/javascript/config.el
index d125e96e3..31b4804e5 100644
--- a/modules/lang/javascript/config.el
+++ b/modules/lang/javascript/config.el
@@ -122,7 +122,12 @@
 ;;
 ;; Tools
 
+(when (featurep! +lsp)
+  (add-hook! (js2-mode rjsx-mode typescript-mode) #'+lsp|init))
+
+
 (def-package! tide
+  :unless (featurep! +lsp)
   :defer t
   :init
   ;; Don't let hard errors stop the user from opening js files.
diff --git a/modules/lang/javascript/packages.el b/modules/lang/javascript/packages.el
index e281c0b8f..c7474537c 100644
--- a/modules/lang/javascript/packages.el
+++ b/modules/lang/javascript/packages.el
@@ -1,17 +1,21 @@
 ;; -*- no-byte-compile: t; -*-
 ;;; lang/javascript/packages.el
 
+;; major modes
 (package! coffee-mode)
-(package! eslintd-fix)
 (package! js2-mode)
+(package! rjsx-mode)
+(package! typescript-mode)
+
+;; tools
+(package! eslintd-fix)
 (package! js2-refactor)
 (package! nodejs-repl)
-(package! rjsx-mode)
-(package! skewer-mode)
-(package! tide)
-(package! typescript-mode)
 (package! npm-mode)
+(package! skewer-mode)
 
 (when (featurep! :feature lookup)
   (package! xref-js2))
 
+(unless (featurep! +lsp)
+  (package! tide))
diff --git a/modules/lang/ocaml/config.el b/modules/lang/ocaml/config.el
index f5a5df757..87445332c 100644
--- a/modules/lang/ocaml/config.el
+++ b/modules/lang/ocaml/config.el
@@ -1,5 +1,9 @@
 ;;; lang/ocaml/config.el -*- lexical-binding: t; -*-
 
+(when (featurep! +lsp)
+  (add-hook! (tuareg-mode reason-mode) #'+lsp|init))
+
+
 (after! tuareg
   ;; tuareg-mode has the prettify symbols itself
   (set-pretty-symbols! 'tuareg-mode :alist
@@ -18,6 +22,7 @@
 
 
   (def-package! merlin
+    :unless (featurep! +lsp)
     :defer t
     :init
     (defun +ocaml|init-merlin ()
@@ -37,7 +42,20 @@
     (map! :localleader
           :map tuareg-mode-map
           "t" #'merlin-type-enclosing
-          "a" #'tuareg-find-alternate-file))
+          "a" #'tuareg-find-alternate-file)
+
+    (def-package! merlin-eldoc
+      :hook (merlin-mode . merlin-eldoc-setup))
+
+    (def-package! merlin-iedit
+      :when (featurep! :editor multiple-cursors)
+      :config
+      (map! :map tuareg-mode-map
+            :v "R" #'merlin-iedit-occurrences))
+
+    (def-package! merlin-imenu
+      :when (featurep! :emacs imenu)
+      :hook (merlin-mode . merlin-use-merlin-imenu)))
 
 
   (def-package! flycheck-ocaml
@@ -53,22 +71,6 @@
     (add-hook 'merlin-mode-hook #'+ocaml|init-flycheck))
 
 
-  (def-package! merlin-eldoc
-    :hook (merlin-mode . merlin-eldoc-setup))
-
-
-  (def-package! merlin-iedit
-    :when (featurep! :editor multiple-cursors)
-    :config
-    (map! :map tuareg-mode-map
-          :v "R" #'merlin-iedit-occurrences))
-
-
-  (def-package! merlin-imenu
-    :when (featurep! :emacs imenu)
-    :hook (merlin-mode . merlin-use-merlin-imenu))
-
-
   (def-package! utop
     :when (featurep! :feature eval)
     :defer t  ; loaded by hook below
diff --git a/modules/lang/php/config.el b/modules/lang/php/config.el
index c14f73f6d..b3e8ae1d8 100644
--- a/modules/lang/php/config.el
+++ b/modules/lang/php/config.el
@@ -12,9 +12,11 @@
   (set-lookup-handlers! 'php-mode :documentation #'php-search-documentation)
   (set-formatter! 'php-mode #'php-cs-fixer-fix)
 
-  ;; `+php-company-backend' uses `company-phpactor', `php-extras-company' or
-  ;; `company-dabbrev-code', in that order.
-  (set-company-backend! 'php-mode '+php-company-backend 'company-dabbrev-code)
+  (if (featurep! +lsp)
+      (add-hook 'php-mode-hook #'+lsp|init)
+    ;; `+php-company-backend' uses `company-phpactor', `php-extras-company' or
+    ;; `company-dabbrev-code', in that order.
+    (set-company-backend! 'php-mode '+php-company-backend 'company-dabbrev-code))
 
   ;; Use the smallest `sp-max-pair-length' for optimum `smartparens' performance
   (setq-hook! 'php-mode-hook sp-max-pair-length 5)
@@ -32,6 +34,7 @@
 
 
 (def-package! phpactor
+  :unless (featurep! +lsp)
   :after php-mode
   :config
   (set-lookup-handlers! 'php-mode
diff --git a/modules/lang/php/packages.el b/modules/lang/php/packages.el
index b7f9da3bd..61f3ce303 100644
--- a/modules/lang/php/packages.el
+++ b/modules/lang/php/packages.el
@@ -5,9 +5,10 @@
 (package! php-extras :recipe (:fetcher github :repo "arnested/php-extras"))
 (package! php-mode)
 (package! php-refactor-mode)
-(package! phpactor :recipe (:fetcher github :repo "emacs-php/phpactor.el" :files ("*")))
 (package! phpunit)
 
 (when (featurep! +hack)
   (package! hack-mode :recipe (:fetcher github :repo "hhvm/hack-mode")))
 
+(unless (featurep! +lsp)
+  (package! phpactor :recipe (:fetcher github :repo "emacs-php/phpactor.el" :files ("*"))))
diff --git a/modules/lang/python/config.el b/modules/lang/python/config.el
index 30bac7222..717725a4e 100644
--- a/modules/lang/python/config.el
+++ b/modules/lang/python/config.el
@@ -46,6 +46,9 @@ called.")
     :for "for"
     :return "return" :yield "yield")
 
+  (when (featurep! +lsp)
+    (add-hook 'python-mode-hook #'+lsp|init))
+
   (define-key python-mode-map (kbd "DEL") nil) ; interferes with smartparens
   (sp-local-pair 'python-mode "'" nil
                  :unless '(sp-point-before-word-p
@@ -63,6 +66,7 @@ called.")
 
 
 (def-package! anaconda-mode
+  :unless (featurep! +lsp)
   :hook python-mode
   :init
   (setq anaconda-mode-installation-directory (concat doom-etc-dir "anaconda/")
diff --git a/modules/lang/python/packages.el b/modules/lang/python/packages.el
index cfe418184..f492a90d9 100644
--- a/modules/lang/python/packages.el
+++ b/modules/lang/python/packages.el
@@ -17,6 +17,7 @@
   (package! conda))
 
 ;; Programming environment
-(when (package! anaconda-mode)
+(unless (featurep! +lsp)
+  (package! anaconda-mode)
   (when (featurep! :completion company)
     (package! company-anaconda)))
diff --git a/modules/lang/ruby/config.el b/modules/lang/ruby/config.el
index 16eb2cbff..cb391bd37 100644
--- a/modules/lang/ruby/config.el
+++ b/modules/lang/ruby/config.el
@@ -26,6 +26,9 @@
   (set-electric! '(ruby-mode enh-ruby-mode) :words '("else" "end" "elsif"))
   (set-repl-handler! '(ruby-mode enh-ruby-mode) #'inf-ruby)
 
+  (when (featurep! +lsp)
+    (add-hook 'enh-ruby-mode-hook #'+lsp|init))
+
   (after! company-dabbrev-code
     (add-to-list 'company-dabbrev-code-modes 'enh-ruby-mode nil #'eq)
     (add-to-list 'company-dabbrev-code-modes 'ruby-mode nil #'eq))
@@ -42,6 +45,7 @@
 
 
 (def-package! robe
+  :unless (featurep! +lsp)
   :hook (enh-ruby-mode . robe-mode)
   :config
   (set-repl-handler! 'enh-ruby-mode #'robe-start)
diff --git a/modules/lang/rust/config.el b/modules/lang/rust/config.el
index 39ebcb0f0..ff32dd429 100644
--- a/modules/lang/rust/config.el
+++ b/modules/lang/rust/config.el
@@ -5,6 +5,9 @@
   (set-docsets! 'rust-mode "Rust")
   (setq rust-indent-method-chain t)
 
+  (when (featurep! +lsp)
+    (add-hook 'rust-mode-hook #'+lsp|init))
+
   (map! :map rust-mode-map
         :localleader
         :prefix "b"
@@ -15,6 +18,7 @@
 
 
 (def-package! racer
+  :unless (featurep! +lsp)
   :after rust-mode
   :config
   (add-hook 'rust-mode-hook #'racer-mode)
@@ -27,4 +31,3 @@
   :when (featurep! :feature syntax-checker)
   :after rust-mode
   :config (add-hook 'rust-mode-hook #'flycheck-rust-setup))
-
diff --git a/modules/lang/scala/config.el b/modules/lang/scala/config.el
index 29f5ae5f1..96870e0b5 100644
--- a/modules/lang/scala/config.el
+++ b/modules/lang/scala/config.el
@@ -6,7 +6,10 @@
     (add-to-list 'dtrt-indent-hook-mapping-list '(scala-mode c/c++/java scala-indent:step))))
 
 
-(after! ensime
+(def-package! ensime
+  :unless (featurep! +lsp)
+  :defer t
+  :config
   (setq ensime-startup-snapshot-notification nil
         ensime-startup-notification nil
         ensime-eldoc-hints 'all
@@ -23,3 +26,9 @@
 (def-package! sbt-mode
   :after scala-mode
   :config (set-repl-handler! 'scala-mode #'run-scala))
+
+
+(def-package! lsp-scala
+  :when (featurep! +lsp)
+  :after scala-mode
+  :init (add-hook 'scala-mode-hook #'+lsp|init))
diff --git a/modules/lang/scala/packages.el b/modules/lang/scala/packages.el
index c458f6851..83207fe79 100644
--- a/modules/lang/scala/packages.el
+++ b/modules/lang/scala/packages.el
@@ -1,6 +1,9 @@
 ;; -*- no-byte-compile: t; -*-
 ;;; lang/scala/packages.el
 
-(package! ensime)
 (package! sbt-mode)
 (package! scala-mode)
+
+(if (featurep! +lsp)
+    (package! lsp-scala)
+  (package! ensime))
diff --git a/modules/lang/swift/config.el b/modules/lang/swift/config.el
index 6925ab766..a41d85306 100644
--- a/modules/lang/swift/config.el
+++ b/modules/lang/swift/config.el
@@ -5,14 +5,21 @@
 
 
 (def-package! flycheck-swift
-  :when (featurep! :feature syntax-checker)
+  :when (and (featurep! :feature syntax-checker)
+             (not (featurep! +lsp)))
   :after swift-mode
   :config (flycheck-swift-setup))
 
 
 (def-package! company-sourcekit
-  :when (featurep! :completion company)
+  :when (and (featurep! :completion company)
+             (not (featurep! +lsp)))
   :after swift-mode
   :config
   (set-company-backend! 'swift-mode '(company-sourcekit company-yasnippet)))
 
+
+(def-package! lsp-sourcekit
+  :when (featurep! +lsp)
+  :after swift-mode
+  :init (add-hook 'swift-mode-hook #'+lsp|init))
diff --git a/modules/lang/swift/packages.el b/modules/lang/swift/packages.el
index 73e74da91..baec9033f 100644
--- a/modules/lang/swift/packages.el
+++ b/modules/lang/swift/packages.el
@@ -3,8 +3,9 @@
 
 (package! swift-mode)
 
-(when (featurep! :completion company)
-  (package! company-sourcekit))
-
-(when (featurep! :feature syntax-checker)
-  (package! flycheck-swift))
+(if (featurep! +lsp)
+    (package! lsp-sourcekit)
+  (when (featurep! :completion company)
+    (package! company-sourcekit))
+  (when (featurep! :feature syntax-checker)
+    (package! flycheck-swift)))
diff --git a/modules/lang/web/+css.el b/modules/lang/web/+css.el
index fc7d45e75..2c9ea541e 100644
--- a/modules/lang/web/+css.el
+++ b/modules/lang/web/+css.el
@@ -35,6 +35,10 @@
 ;;
 ;; Tools
 
+(when (featurep! +lsp)
+  (add-hook! (css-mode sass-mode less-css-mode) #'+lsp|init))
+
+
 (def-package! counsel-css
   :when (featurep! :completion ivy)
   :commands counsel-css
diff --git a/modules/lang/web/+html.el b/modules/lang/web/+html.el
index 06d6cd721..e11894818 100644
--- a/modules/lang/web/+html.el
+++ b/modules/lang/web/+html.el
@@ -139,3 +139,7 @@
   (set-company-backend! 'web-mode 'company-web-html))
 (after! slim-mode
   (set-company-backend! 'slim-mode 'company-web-slim))
+
+
+(when (featurep! +lsp)
+  (add-hook! (html-mode web-mode) #'+lsp|init))
diff --git a/modules/tools/lsp/autoload.el b/modules/tools/lsp/autoload.el
new file mode 100644
index 000000000..c13d9efd7
--- /dev/null
+++ b/modules/tools/lsp/autoload.el
@@ -0,0 +1,7 @@
+;;; feature/lsp/autoload.el -*- lexical-binding: t; -*-
+
+;;;###autoload
+(defun +lsp|init ()
+  "Enable LSP as late as possible, to allow users to customize it via file or
+dir local variables."
+  (add-hook 'hack-local-variables-hook #'lsp nil t))
diff --git a/modules/tools/lsp/config.el b/modules/tools/lsp/config.el
new file mode 100644
index 000000000..e2e690289
--- /dev/null
+++ b/modules/tools/lsp/config.el
@@ -0,0 +1,21 @@
+;;; tools/lsp/config.el -*- lexical-binding: t; -*-
+
+(def-package! lsp-ui
+  :hook (lsp-mode . lsp-ui-mode)
+  :config
+  (setq lsp-prefer-flymake nil
+        lsp-ui-doc-max-height 8
+        lsp-ui-doc-max-width 35
+        lsp-ui-sideline-ignore-duplicate t)
+  (define-key! lsp-ui-mode-map
+    [remap xref-find-definitions] #'lsp-ui-peek-find-definitions
+    [remap xref-find-references]  #'lsp-ui-peek-find-references)
+  (set-lookup-handlers! 'lsp-ui-mode
+    :definition #'lsp-ui-peek-find-definitions
+    :references #'lsp-ui-peek-find-references))
+
+(def-package! company-lsp
+  :when (featurep! :completion company)
+  :after lsp-mode
+  :config
+  (set-company-backend! 'lsp-mode 'company-lsp))
diff --git a/modules/tools/lsp/packages.el b/modules/tools/lsp/packages.el
new file mode 100644
index 000000000..efcc53bd1
--- /dev/null
+++ b/modules/tools/lsp/packages.el
@@ -0,0 +1,7 @@
+;; -*- no-byte-compile: t; -*-
+;;; tools/lsp/packages.el
+
+(package! lsp-mode)
+(package! lsp-ui)
+(when (featurep! :completion company)
+  (package! company-lsp))