feat(hues): add get_palette()

Details:
- With presence of `apply_palette()`, the actually applied palette might
  be different from the `MiniHues.make_palette(MiniHues.config)`.
  So there should be some way to get currently "active" palette.

Author: echasnovski

CHANGELOG.md

@@ -47,6 +47,10 @@ There are following change types:
 
 - Make black (0 and 8) and white (7 and 15) colors for built-in terminal different from regular background and foreground. This improves color coverage and does not affect default uncolored text (it is highlighted as `Normal`).
 
+### Expand
+
+- Add `get_palette()` function.
+
 ## mini.jump
 
 ### Expand

doc/mini-hues.txt

@@ -309,6 +309,9 @@ Return ~
   - <accent> and <accent_bg> represent accent colors with foreground and
     background lightness values.
 
+See also ~
+|MiniHues.get_palette()|
+
 ------------------------------------------------------------------------------
                                                       *MiniHues.apply_palette()*
                  `MiniHues.apply_palette`({palette}, {plugins})
@@ -334,6 +337,18 @@ Usage ~
   palette.cyan_bg = '#004629'
   require('mini.hues').apply_palette(palette)
 <
+See also ~
+|MiniHues.get_palette()|
+
+------------------------------------------------------------------------------
+                                                        *MiniHues.get_palette()*
+                            `MiniHues.get_palette`()
+Get latest applied palette
+
+Return ~
+`(table)` Table with structure as |MiniHues.make_palette()| output that was
+  the latest applied (via |MiniHues.apply_palette()|) palette.
+
 ------------------------------------------------------------------------------
                                              *MiniHues.gen_random_base_colors()*
                    `MiniHues.gen_random_base_colors`({opts})

lua/mini/hues.lua

@@ -314,6 +314,8 @@ MiniHues.config = {
 ---     background.
 ---   - <accent> and <accent_bg> represent accent colors with foreground and
 ---     background lightness values.
+---
+---@seealso |MiniHues.get_palette()|
 MiniHues.make_palette = function(config)
   config = vim.tbl_deep_extend('force', MiniHues.config, config or {})
   local bg = H.validate_hex(config.background, 'background')
@@ -420,11 +422,14 @@ end
 ---   palette.cyan_bg = '#004629'
 ---   require('mini.hues').apply_palette(palette)
 --- <
+---@seealso |MiniHues.get_palette()|
 MiniHues.apply_palette = function(palette, plugins)
   if type(palette) ~= 'table' then H.error('`palette` should be table with palette colors.') end
   plugins = plugins or MiniHues.config.plugins
   if type(plugins) ~= 'table' then H.error('`plugins` should be table with plugin integrations data.') end
 
+  H.palette = vim.deepcopy(palette)
+
   -- Prepare highlighting application. Notes:
   -- - Clear current highlight only if other theme was loaded previously.
   -- - No need to `syntax reset` because *all* syntax groups are defined later.
@@ -1506,6 +1511,12 @@ MiniHues.apply_palette = function(palette, plugins)
   vim.g.terminal_color_15 = p[white .. '_edge2']
 end
 
+--- Get latest applied palette
+---
+---@return table Table with structure as |MiniHues.make_palette()| output that was
+---   the latest applied (via |MiniHues.apply_palette()|) palette.
+MiniHues.get_palette = function() return vim.deepcopy(H.palette) end
+
 --- Generate random base colors
 ---
 --- Compute background and foreground colors based on randomly generated hue
@@ -1622,6 +1633,9 @@ H.cusps = {
 }
 --stylua: ignore end
 
+-- Latest applied palette
+H.palette = nil
+
 -- Helper functionality =======================================================
 -- Settings -------------------------------------------------------------------
 H.setup_config = function(config)

tests/test_hues.lua

@@ -494,6 +494,31 @@ T['apply_palette()']['validates input'] = function()
   expect.error(function() apply_palette(palette, 'a') end, '`plugins`.*table')
 end
 
+T['get_palette()'] = new_set()
+
+T['get_palette()']['works'] = function()
+  local res = child.lua([[
+    local palette = MiniHues.make_palette({ background = '#222222', foreground = '#dddddd' })
+    palette.fg = '#aaaaaa'
+    MiniHues.apply_palette(palette)
+
+    local res_palette = MiniHues.get_palette()
+    local is_same = vim.deep_equal(palette, res_palette)
+
+    -- Should not be affected by change in applied palette
+    palette.bg = '#000000'
+    local is_same_1 = vim.deep_equal(palette, res_palette)
+
+    -- Should return copy
+    res_palette.bg = '#000000'
+    local is_same_2 = vim.deep_equal(MiniHues.get_palette(), res_palette)
+
+    return { is_same, is_same_1, is_same_2 }
+  ]])
+
+  eq(res, { true, false, false })
+end
+
 T['gen_random_base_colors()'] = new_set()
 
 T['gen_random_base_colors()']['works'] = function()