nvim/diagnostic: configure neovim's diagnostics API

Basic run down is:

- Disable virtual_text
- Add severity icons
- Add key maps for goto prev/next diagnostic
- Add diagnostic popup on hover

nvim/lua/psoxizsh/diagnostic.lua

@@ -0,0 +1,57 @@
+local au, keys = require 'psoxizsh.autocmd', require 'psoxizsh.key.map'
+local D = vim.diagnostic
+
+local M = setmetatable({}, { __call = function(self, args) self.setup(args) end })
+
+local sign = function(o)
+  vim.fn.sign_define(o.name, {
+    texthl = o.name,
+    text = o.text,
+    numhl = ''
+  })
+end
+
+function M.config()
+  -- Setup signs
+  sign({ name = 'DiagnosticSignError', text = '' })
+  sign({ name = 'DiagnosticSignWarn',  text = '' })
+  sign({ name = 'DiagnosticSignHint',  text = '' })
+  sign({ name = 'DiagnosticSignInfo',  text = '' })
+
+  -- Define base diagnostic configuration
+  D.config({
+    virtual_text      = false,
+    signs             = true,
+    update_in_insert  = true,
+    underline         = true,
+    severity_sort     = true,
+
+    float = {
+        border = 'rounded',
+        source = 'if_many',
+        header = '',
+        prefix = '',
+    },
+  })
+end
+
+
+-- Key maps
+function M.keymaps()
+  keys.Global.N.DiagnosticPrev { action = D.goto_prev }
+  keys.Global.N.DiagnosticNext { action = D.goto_next }
+end
+
+function M.autocmds()
+  au.PsoxDiagnosticHover {
+    { 'CursorHold', '*', function() D.open_float({ focusable = false, scope = 'cursor' }) end }
+  }
+end
+
+function M.setup(_)
+  M.config()
+  M.keymaps()
+  M.autocmds()
+end
+
+return M

nvim/lua/psoxizsh/init.lua

@@ -1,5 +1,6 @@
 local o, g, fn, cmd = vim.opt, vim.g, vim.fn, vim.cmd
 local au, util = require 'psoxizsh.autocmd', require 'psoxizsh.util'
+local diagnostic = require 'psoxizsh.diagnostic'
 local keys = require 'psoxizsh.key.map'
 
 local function psoxizsh_early_config()
@@ -73,6 +74,9 @@ local function psoxizsh_early_config()
   -- Set global statusline (0.7+ only)
   if fn.has('nvim-0.7') == 1 then o.laststatus = 3 end
 
+  -- Setup vim.diagnostic APIs
+  diagnostic.setup {}
+
   -- Local pre plugin configuration
   util.try_mreload('pre')
 end

nvim/lua/psoxizsh/key/map.lua

@@ -40,6 +40,11 @@ M.Global.N {
   --
   BufferNext = B { 'Next buffer or tab'     , key = '<Tab>'   , action = '<cmd>BufferLineCycleNext<CR>' , } ,
   BufferPrev = B { 'Previous buffer or tab' , key = '<S-Tab>' , action = '<cmd>BufferLineCyclePrev<CR>' , } ,
+  --
+  -- Diagnostics
+  --
+  DiagnosticNext = B { 'Next buffer diagnostic'     , key = ']g' , } ,
+  DiagnosticPrev = B { 'Previous buffer diagnostic' , key = '[g' , } ,
 }
 
 -- #############################