feat: make borders configurable

And switch to a more compact default:

    ┌─ CommandT [rg] ───────────────────────────────────────────┐
    │>                                                          │
    └───────────────────────────────────────────────────────────┘
     > CODE_OF_CONDUCT.md
       CONTRIBUTING.md
       Gemfile
       Gemfile.lock
       LICENSE.md
       Makefile
       README.md
       appstream/vim-command-t.metainfo.xml
       autoload/commandt.vim
       autoload/commandt/private.vim
       bin/benchmarks/matcher.lua
       bin/benchmarks/matcher.rb
       bin/benchmarks/scanner.lua
       bin/benchmarks/watchman.rb
       bin/check-format
       bin/check-tag
       bin/create-archive
       bin/format
       bin/help
       bin/spec
       bin/symbolicate-dtrace
       bin/test
       bin/test.lua
       compile_flags.txt
       data/benchmark.yml
       data/wincent/commandt/benchmark/configs/matcher.lua
       data/wincent/commandt/benchmark/configs/scanner.lua
       doc/command-t-ruby.txt
       doc/command-t.txt
       fixtures/bar/abc

ie.

- prompt goes from "rounded" to "single"
- match listing goes from "rounded" to:
  - no border on top or bottom
  - blank space on right and left

doc/command-t.txt

@@ -412,9 +412,19 @@ are documented and they could change without notice at any time; for example:
         },
       },
       margin = 10,
+      match_listing = {
+        -- 'double', 'none', 'rounded', 'shadow', 'single', 'solid', or a
+        -- list of strings.
+        border = { '', '', '', ' ', '', '', '', ' '},
+      },
       never_show_dot_files = false,
       order = 'forward', -- 'forward' or 'reverse'.
       position = 'center', -- 'bottom', 'center' or 'top'.
+      prompt = {
+        -- 'double', 'none', 'rounded', 'shadow', 'single', 'solid', or a
+        -- list of strings.
+        border = 'single',
+      },
       open = function(item, kind)
         commandt.open(item, kind)
       end,

lua/wincent/commandt/init.lua

@@ -114,9 +114,45 @@ local options_spec = {
         end
       end,
     },
+    match_listing = {
+      kind = 'table',
+      keys = {
+        border = {
+          kind = {
+            one_of = {
+              'double',
+              'none',
+              'rounded',
+              'shadow',
+              'single',
+              'solid',
+              { kind = 'list', of = { kind = 'string' } },
+            },
+          },
+        },
+      },
+    },
     never_show_dot_files = { kind = 'boolean' },
     order = { kind = { one_of = { 'forward', 'reverse' } } },
     position = { kind = { one_of = { 'bottom', 'center', 'top' } } },
+    prompt = {
+      kind = 'table',
+      keys = {
+        border = {
+          kind = {
+            one_of = {
+              'double',
+              'none',
+              'rounded',
+              'shadow',
+              'single',
+              'solid',
+              { kind = 'list', of = { kind = 'string' } },
+            },
+          },
+        },
+      },
+    },
     open = { kind = 'function' },
     scanners = {
       kind = 'table',
@@ -408,9 +444,15 @@ local default_options = {
     },
   },
   margin = 10,
+  match_listing = {
+    border = { '', '', '', ' ', '', '', '', ' ' }, -- 'double', 'none', 'rounded', 'shadow', 'single', 'solid', or a list of strings.
+  },
   never_show_dot_files = false,
   order = 'forward', -- 'forward', 'reverse'.
   position = 'center', -- 'bottom', 'center', 'top'.
+  prompt = {
+    border = 'single', -- 'double', 'none', 'rounded', 'shadow', 'single', 'solid', or a list of strings.
+  },
   open = open,
   scanners = {
     file = {

lua/wincent/commandt/private/match_listing.lua

@@ -17,13 +17,15 @@ local mt = {
 
 function MatchListing.new(options)
   options = merge({
+    border = { '', '', '', ' ', '', '', '', ' ' },
     height = 15,
     margin = 0,
     position = 'bottom',
     selection_highlight = 'PMenuSel',
   }, options or {})
   -- TODO: validate options
   local m = {
+    _border = options.border,
     _height = options.height,
     _margin = options.margin,
     _position = options.position,
@@ -112,6 +114,7 @@ function MatchListing:show()
   -- TODO: deal with other options, like reverse
   if self._window == nil then
     self._window = Window.new({
+      border = self._border,
       bottom = bottom,
       description = 'CommandT [match listing]',
       filetype = 'CommandTMatchListing',

lua/wincent/commandt/private/prompt.lua

@@ -21,6 +21,7 @@ local mt = {
 
 function Prompt.new(options)
   options = merge({
+    border = 'single',
     mappings = {},
     margin = 0,
     height = 15,
@@ -33,6 +34,7 @@ function Prompt.new(options)
   }, options or {})
   -- TODO validate options
   local p = {
+    _border = options.border,
     _height = options.height,
     _mappings = options.mappings,
     _margin = options.margin,
@@ -83,6 +85,7 @@ function Prompt:show()
 
   if self._window == nil then
     self._window = Window.new({
+      border = self._border,
       bottom = bottom,
       buftype = 'prompt',
       filetype = 'CommandTPrompt',

lua/wincent/commandt/private/ui.lua

@@ -80,6 +80,7 @@ ui.show = function(finder, options)
   current_window = vim.api.nvim_get_current_win()
 
   match_listing = MatchListing.new({
+    border = options.match_listing.border,
     height = options.height,
     margin = options.margin,
     position = options.position,
@@ -90,6 +91,7 @@ ui.show = function(finder, options)
   results = nil
   selected = nil
   prompt = Prompt.new({
+    border = options.prompt.border,
     height = options.height,
     mappings = options.mappings,
     margin = options.margin,

lua/wincent/commandt/private/window.lua

@@ -58,6 +58,7 @@ end
 
 function Window.new(options)
   options = merge({
+    border = 'single',
     bottom = nil,
     buftype = 'nofile', -- Also, 'prompt'.
     filetype = nil,
@@ -74,6 +75,7 @@ function Window.new(options)
   }, options)
   validate_options(options)
   local w = {
+    _border = options.border,
     _bottom = options.bottom,
     _buftype = options.buftype,
     _description = options.description,
@@ -266,7 +268,7 @@ function Window:show()
       self._main_buffer,
       false, -- enter = false
       merge({
-        border = 'rounded', -- TODO make configurable
+        border = self._border,
         focusable = false,
         noautocmd = true,
         relative = 'editor',