Modularize ggtags with eldoc configuration

See PHP layer packages.el for an example

contrib/gtags/packages.el

@@ -12,45 +12,10 @@
 
 (setq gtags-packages
   '(
-    ;; package gtagss go here
     helm-gtags
     ggtags
     ))
 
-;; For each package, define a function gtags/init-<package-gtags>
-;;
-(defun spacemacs/gtags-define-keys-for-mode (mode)
-  "Define key bindings for the specific MODE."
-  (when (fboundp mode)
-    (let ((hook (intern (concat (symbol-name mode) "-hook"))))
-      (message "hook is %s" hook)
-      (add-hook hook 'helm-gtags-mode)
-      (unless (member mode '(c-mode
-                             c++-mode
-                             lisp-mode
-                             emacs-lisp-mode
-                             python-mode
-                             ruby-mode))
-        (add-hook hook (lambda ()
-                         (ggtags-mode 1)
-                         (eldoc-mode 1)
-                         (setq-local eldoc-documentation-function #'ggtags-eldoc-function)))))
-
-    (evil-leader/set-key-for-mode mode
-      "mgc" 'helm-gtags-create-tags
-      "mgd" 'helm-gtags-find-tag
-      "mgf" 'helm-gtags-select-path
-      "mgg" 'helm-gtags-dwim
-      "mgi" 'helm-gtags-tags-in-this-function
-      "mgl" 'helm-gtags-parse-file
-      "mgn" 'helm-gtags-next-history
-      "mgp" 'helm-gtags-previous-history
-      "mgr" 'helm-gtags-find-rtag
-      "mgR" 'helm-gtags-resume
-      "mgs" 'helm-gtags-select
-      "mgS" 'helm-gtags-show-stack
-      "mgu" 'helm-gtags-update-tags)))
-
 (defun gtags/init-ggtags ()
   (use-package ggtags
     :defer t))
@@ -65,14 +30,13 @@
             helm-gtags-use-input-at-cursor t
             helm-gtags-pulse-at-cursor t)
       ;; modes that do not have a layer, define here
-      (spacemacs/gtags-define-keys-for-mode 'tcl-mode)
-      (spacemacs/gtags-define-keys-for-mode 'java-mode)
-      (spacemacs/gtags-define-keys-for-mode 'vhdl-mode)
-      (spacemacs/gtags-define-keys-for-mode 'shell-script-mode)
-      (spacemacs/gtags-define-keys-for-mode 'awk-mode)
-      (spacemacs/gtags-define-keys-for-mode 'asm-mode)
-      (spacemacs/gtags-define-keys-for-mode 'dired-mode)
-      )
+      (spacemacs/helm-gtags-define-keys-for-mode 'tcl-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'java-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'vhdl-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'shell-script-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'awk-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'asm-mode)
+      (spacemacs/helm-gtags-define-keys-for-mode 'dired-mode))
     :config
     (progn
       ;; if anyone uses helm-gtags, they would want to use these key bindings

contrib/lang/c-c++/packages.el

@@ -50,8 +50,8 @@
   (add-to-hooks 'flycheck-mode '(c-mode-hook c++-mode-hook)))
 
 (defun c-c++/post-init-helm-gtags ()
-  (spacemacs/gtags-define-keys-for-mode 'c-mode)
-  (spacemacs/gtags-define-keys-for-mode 'c++-mode))
+  (spacemacs/helm-gtags-define-keys-for-mode 'c-mode)
+  (spacemacs/helm-gtags-define-keys-for-mode 'c++-mode))
 
 (defun c-c++/post-init-srefactor ()
   (semantic/enable-semantic-mode 'c-mode)

contrib/lang/php/packages.el

@@ -29,15 +29,17 @@
     :defer t))
 
 (defun php/post-init-eldoc ()
-  (add-hook 'php-mode-hook 'eldoc-mode))
+  (add-hook 'php-mode-hook 'eldoc-mode)
+  (when (configuration-layer/package-usedp 'ggtags)
+    (add-hook 'php-mode-hook
+              (lambda () (setq-local eldoc-documentation-function
+                                     #'ggtags-eldoc-function)))))
 
 (defun php/post-init-ggtags ()
-  (when (configuration-layer/package-usedp 'eldoc)
-    (add-hook 'php-mode-hook 'setq-local eldoc-documentation-function
-              'ggtags-eldoc-function)))
+  (add-hook php-mode-hook 'ggtags-mode))
 
 (defun php/post-init-helm-gtags ()
-  (spacemacs/gtags-define-keys-for-mode 'php-mode))
+  (spacemacs/helm-gtags-define-keys-for-mode 'php-mode))
 
 (defun php/init-php-auto-yasnippets ()
   (use-package php-auto-yasnippets