feat(ansi): better logging and option to disab;e

doc/cp.txt

@@ -148,6 +148,7 @@ Here's an example configuration with lazy.nvim: >lua
             scrapers = { 'atcoder', 'codeforces', 'cses' },
             filename = default_filename,  -- <contest id> + <problem id>
             run_panel = {
+                ansi = true,
                 diff_mode = 'vim',
                 next_test_key = '<c-n>',
                 prev_test_key = '<c-p>',
@@ -199,6 +200,12 @@ Here's an example configuration with lazy.nvim: >lua
 
                                                         *cp.RunPanelConfig*
     Fields: ~
+        {ansi}            (boolean, default: true) Enable ANSI color parsing and
+                          highlighting. When true, compiler output and test results
+                          display with colored syntax highlighting. When false,
+                          ANSI escape codes are stripped for plain text display.
+                          Requires vim.g.terminal_color_* to be configured for
+                          proper color display.
         {diff_mode}       (string, default: "vim") Diff backend: "vim" or "git".
                           Git provides character-level precision, vim uses
                           built-in diff.

lua/cp/ansi.lua

@@ -192,6 +192,24 @@ function M.setup_highlight_groups()
     BrightWhite = vim.g.terminal_color_15,
   }
 
+  local missing_colors = {}
+  for color_name, terminal_color in pairs(color_map) do
+    if terminal_color == nil then
+      table.insert(missing_colors, color_name)
+    end
+  end
+
+  if #missing_colors > 0 then
+    vim.notify(
+      string.format(
+        '[cp.nvim] Terminal colors not configured: %s. ANSI colors will not display properly. '
+          .. 'Set vim.g.terminal_color_* variables or use a colorscheme that provides them.',
+        table.concat(missing_colors, ', ')
+      ),
+      vim.log.levels.WARN
+    )
+  end
+
   local combinations = {
     { bold = false, italic = false },
     { bold = true, italic = false },
@@ -202,7 +220,7 @@ function M.setup_highlight_groups()
   for _, combo in ipairs(combinations) do
     for color_name, terminal_color in pairs(color_map) do
       local parts = { 'CpAnsi' }
-      local opts = { fg = terminal_color }
+      local opts = { fg = terminal_color or 'NONE' }
 
       if combo.bold then
         table.insert(parts, 'Bold')

lua/cp/config.lua

@@ -30,6 +30,7 @@
 ---@field setup_code? fun(ctx: ProblemContext)
 
 ---@class RunPanelConfig
+---@field ansi boolean Enable ANSI color parsing and highlighting
 ---@field diff_mode "vim"|"git" Diff backend to use
 ---@field next_test_key string Key to navigate to next test case
 ---@field prev_test_key string Key to navigate to previous test case
@@ -97,6 +98,7 @@ M.defaults = {
   scrapers = constants.PLATFORMS,
   filename = nil,
   run_panel = {
+    ansi = true,
     diff_mode = 'vim',
     next_test_key = '<c-n>',
     prev_test_key = '<c-p>',
@@ -186,6 +188,11 @@ function M.setup(user_config)
   })
 
   vim.validate({
+    ansi = {
+      config.run_panel.ansi,
+      'boolean',
+      'ansi color parsing must be enabled xor disabled',
+    },
     diff_mode = {
       config.run_panel.diff_mode,
       function(value)

lua/cp/init.lua

@@ -537,8 +537,10 @@ local function toggle_run_panel(is_debug)
   refresh_run_panel()
 
   vim.schedule(function()
-    local ansi = require('cp.ansi')
-    ansi.setup_highlight_groups()
+    if config.run_panel.ansi then
+      local ansi = require('cp.ansi')
+      ansi.setup_highlight_groups()
+    end
     if current_diff_layout then
       update_diff_panes()
     end

lua/cp/run.lua

@@ -241,9 +241,13 @@ local function run_single_test_case(ctx, contest_config, cp_config, test_case)
   local actual_highlights = {}
 
   if actual_output ~= '' then
-    local parsed = ansi.parse_ansi_text(actual_output)
-    actual_output = table.concat(parsed.lines, '\n')
-    actual_highlights = parsed.highlights
+    if cp_config.run_panel.ansi then
+      local parsed = ansi.parse_ansi_text(actual_output)
+      actual_output = table.concat(parsed.lines, '\n')
+      actual_highlights = parsed.highlights
+    else
+      actual_output = actual_output:gsub('\027%[[%d;]*[a-zA-Z]', '')
+    end
   end
 
   local max_lines = cp_config.run_panel.max_output_lines
@@ -362,11 +366,18 @@ end
 
 function M.handle_compilation_failure(compilation_output)
   local ansi = require('cp.ansi')
+  local config = require('cp.config').setup()
 
-  -- Always parse the compilation output - it contains everything now
-  local parsed = ansi.parse_ansi_text(compilation_output or '')
-  local clean_text = table.concat(parsed.lines, '\n')
-  local highlights = parsed.highlights
+  local clean_text
+  local highlights = {}
+
+  if config.run_panel.ansi then
+    local parsed = ansi.parse_ansi_text(compilation_output or '')
+    clean_text = table.concat(parsed.lines, '\n')
+    highlights = parsed.highlights
+  else
+    clean_text = (compilation_output or ''):gsub('\027%[[%d;]*[a-zA-Z]', '')
+  end
 
   for _, test_case in ipairs(run_panel_state.test_cases) do
     test_case.status = 'fail'

spec/ansi_spec.lua

@@ -212,4 +212,32 @@ describe('ansi parser', function()
       assert.is_nil(state.foreground)
     end)
   end)
+
+  describe('setup_highlight_groups', function()
+    it('creates highlight groups with fallback colors when terminal colors are nil', function()
+      local original_colors = {}
+      for i = 0, 15 do
+        original_colors[i] = vim.g['terminal_color_' .. i]
+        vim.g['terminal_color_' .. i] = nil
+      end
+
+      ansi.setup_highlight_groups()
+
+      local highlight = vim.api.nvim_get_hl(0, { name = 'CpAnsiRed' })
+      assert.equals('NONE', highlight.fg)
+
+      for i = 0, 15 do
+        vim.g['terminal_color_' .. i] = original_colors[i]
+      end
+    end)
+
+    it('creates highlight groups with proper colors when terminal colors are set', function()
+      vim.g.terminal_color_1 = '#ff0000'
+
+      ansi.setup_highlight_groups()
+
+      local highlight = vim.api.nvim_get_hl(0, { name = 'CpAnsiRed' })
+      assert.equals('#ff0000', highlight.fg)
+    end)
+  end)
 end)

spec/config_spec.lua

@@ -81,6 +81,16 @@ describe('cp.config', function()
     end)
 
     describe('run_panel config validation', function()
+      it('validates ansi is boolean', function()
+        local invalid_config = {
+          run_panel = { ansi = 'invalid' },
+        }
+
+        assert.has_error(function()
+          config.setup(invalid_config)
+        end, 'ansi color parsing must be enabled xor disabled')
+      end)
+
       it('validates diff_mode values', function()
         local invalid_config = {
           run_panel = { diff_mode = 'invalid' },
@@ -114,6 +124,7 @@ describe('cp.config', function()
       it('accepts valid run_panel config', function()
         local valid_config = {
           run_panel = {
+            ansi = false,
             diff_mode = 'git',
             next_test_key = 'j',
             prev_test_key = 'k',

spec/run_spec.lua

@@ -0,0 +1,65 @@
+describe('run module ANSI processing', function()
+  local run = require('cp.run')
+  local config = require('cp.config')
+
+  describe('ANSI processing modes', function()
+    it('parses ANSI when ansi config is true', function()
+      local test_config = config.setup({ run_panel = { ansi = true } })
+
+      local result = {
+        stdout = 'Hello \027[31mworld\027[0m!',
+        stderr = '',
+        code = 0,
+        ok = true,
+        signal = nil,
+        timed_out = false,
+      }
+
+      local processed = run.process_test_result(result, 'expected_output', test_config)
+
+      assert.equals('Hello world!', processed.actual)
+      assert.equals(1, #processed.actual_highlights)
+      assert.equals('CpAnsiRed', processed.actual_highlights[1].highlight_group)
+    end)
+
+    it('strips ANSI when ansi config is false', function()
+      local test_config = config.setup({ run_panel = { ansi = false } })
+
+      local result = {
+        stdout = 'Hello \027[31mworld\027[0m!',
+        stderr = '',
+        code = 0,
+        ok = true,
+        signal = nil,
+        timed_out = false,
+      }
+
+      local processed = run.process_test_result(result, 'expected_output', test_config)
+
+      assert.equals('Hello world!', processed.actual)
+      assert.equals(0, #processed.actual_highlights)
+    end)
+
+    it('handles compilation failure with ansi disabled', function()
+      local test_config = config.setup({ run_panel = { ansi = false } })
+
+      local compilation_output = 'error.cpp:1:1: \027[1m\027[31merror:\027[0m undefined variable'
+
+      -- Create mock run panel state
+      run._test_set_panel_state({
+        test_cases = {
+          { index = 1, input = 'test', expected = 'expected' },
+        },
+      })
+
+      run.handle_compilation_failure(compilation_output)
+
+      local panel_state = run.get_run_panel_state()
+      local test_case = panel_state.test_cases[1]
+
+      assert.equals('error.cpp:1:1: error: undefined variable', test_case.actual)
+      assert.equals(0, #test_case.actual_highlights)
+      assert.equals('Compilation failed', test_case.error)
+    end)
+  end)
+end)