Add a emacs-ycmd contrib layer.

.gitignore

@@ -34,6 +34,7 @@ tmp/
 server/
 *~
 *.elc
+*.pyc
 /*.zip
 *.db
 python-*-docs-html

contrib/ycmd/Readme.md

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+# YCMD
+
+This contrib layer adds [emacs-ycmd](https://github.com/abingham/emacs-ycmd) support.
+In order to use this layer you must have a local [ycmd](https://github.com/Valloric/ycmd#building) installation
+and must set the `ycmd-server-command` variable to reflect the path to that installation. See the emacs-ycmd
+Readme for more instructions on this.
+
+This package also requires the `company-mode` layer in order to get actual completion rather than just flychecking and
+key bindings.
+
+## Key Bindings
+
+Adds the `SPC m g` go to definition binding to `c++-mode` as well as `SPC m G` for the more imprecise but faster version.
+
+## Configuration
+
+By default this layer only activates ycmd for `c++-mode` so company can provide completion that is better than mere keyword
+completion for all the modes it would otherwise add itself to. If you want ycmd in all sorts of other modes then put this
+snippet in your dotspacemacs init function:
+```elisp
+(setq ycmd/all-the-modes t)
+```
+otherwise you might just want to add it for specific languages like:
+```elisp
+(add-hook 'c++-mode-hook 'ycmd-mode)
+```

contrib/ycmd/global_conf.py

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+import os
+import ycm_core
+
+default_flags = [
+'-Wall',
+'-Wextra',
+'-Werror',
+'-Wc++98-compat',
+'-Wno-long-long',
+'-Wno-variadic-macros',
+'-fexceptions',
+'-DNDEBUG',
+'-std=c++11',
+'-x',
+'c++',
+# This path will only work on OS X, but extra paths that don't exist are not harmful
+'-isystem'
+'/System/Library/Frameworks/Python.framework/Headers',
+'-isystem',
+'/usr/include',
+'-isystem',
+'/usr/local/include',
+'-isystem',
+'/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1',
+'-isystem',
+'/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include',
+]
+
+def DirectoryOfThisScript():
+  return os.path.dirname( os.path.abspath( __file__ ) )
+
+
+def MakeRelativePathsInFlagsAbsolute( flags, working_directory ):
+  if not working_directory:
+    return list( flags )
+  new_flags = []
+  make_next_absolute = False
+  path_flags = [ '-isystem', '-I', '-iquote', '--sysroot=' ]
+  for flag in flags:
+    new_flag = flag
+
+    if make_next_absolute:
+      make_next_absolute = False
+      if not flag.startswith( '/' ):
+        new_flag = os.path.join( working_directory, flag )
+
+    for path_flag in path_flags:
+      if flag == path_flag:
+        make_next_absolute = True
+        break
+
+      if flag.startswith( path_flag ):
+        path = flag[ len( path_flag ): ]
+        new_flag = path_flag + os.path.join( working_directory, path )
+        break
+
+    if new_flag:
+      new_flags.append( new_flag )
+  return new_flags
+
+# Thanks to https://github.com/decrispell/vim-config for this code
+def FlagsForFile( filename, **kwargs ):
+    """ given the source filename, return the compiler flags """
+    opt_basename = '.clang_complete'
+    curr_dir = os.path.dirname(filename)
+    opt_fname = os.path.join(curr_dir, opt_basename)
+    # keep traversing up the tree until we find the file, or hit the root
+    while not os.path.exists(opt_fname):
+        new_dir = os.path.dirname(curr_dir)
+        if new_dir == curr_dir:
+          # we've reached the root of the tree
+          break
+        curr_dir = new_dir
+        opt_fname = os.path.join(curr_dir, opt_basename)
+    try:
+      fd = open(opt_fname, 'r')
+    except IOError:
+        return {'flags': default_flags, 'do_cache': True}
+    flags = [line.strip() for line in fd.readlines()]
+    relative_to = os.path.dirname(opt_fname)
+    flags = MakeRelativePathsInFlagsAbsolute(flags, relative_to)
+    return {
+      'flags': flags, 'do_cache': True
+    }

contrib/ycmd/packages.el

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+(defvar ycmd-packages
+  '(
+    ycmd
+    flycheck-ycmd
+    )
+  "List of all packages to install and/or initialize. Built-in packages
+which require an initialization must be listed explicitly in the list.")
+
+(unless (boundp 'ycmd-server-command)
+  (message "YCMD won't work unless you set the ycmd-server-command variable to the path to a ycmd install."))
+
+(when (member 'company-mode dotspacemacs-configuration-layers)
+  (add-to-list 'ycmd-packages 'company-ycmd))
+
+(defvar ycmd/all-the-modes nil
+  "use ycmd for all the modes it supports, most will only use fancy keyword completion.")
+
+(defun ycmd/init-ycmd ()
+  (use-package ycmd
+    :init
+    (progn
+      (if ycmd/all-the-modes
+          (ycmd-setup)
+        (add-hook 'c++-mode-hook 'ycmd-mode))
+      (setq-default ycmd-global-config
+                    (expand-file-name "~/.emacs.d/contrib/ycmd/global_conf.py")))
+    :config
+    (evil-leader/set-key-for-mode 'c++-mode
+      "mg" 'ycmd-goto
+      "mG" 'ycmd-goto-imprecise)))
+
+(defun ycmd/init-company-ycmd ()
+  (use-package company-ycmd
+    :init (company-ycmd-setup)))
+
+(defun ycmd/init-flycheck-ycmd ()
+  (use-package flycheck-ycmd
+    :init
+    (progn
+      (add-hook 'ycmd-file-parse-result-hook 'flycheck-ycmd--cache-parse-results)
+      (add-to-list 'flycheck-checkers 'ycmd))))