Merge pull request #161 from barrett-ruth/feat/ui/io-view

io view

.github/workflows/luarocks.yaml

@@ -3,7 +3,7 @@ name: Release
 on:
   push:
     tags:
-      - "*"
+      - '*'
   workflow_dispatch:
 
 jobs:

.luarc.json

@@ -1,16 +1,8 @@
 {
   "runtime.version": "Lua 5.1",
-  "runtime.path": [
+  "runtime.path": ["lua/?.lua", "lua/?/init.lua"],
-    "lua/?.lua",
+  "diagnostics.globals": ["vim"],
-    "lua/?/init.lua"
+  "workspace.library": ["$VIMRUNTIME/lua", "${3rd}/luv/library"],
-  ],
-  "diagnostics.globals": [
-    "vim"
-  ],
-  "workspace.library": [
-    "$VIMRUNTIME/lua",
-    "${3rd}/luv/library"
-  ],
   "workspace.checkThirdParty": false,
   "completion.callSnippet": "Replace"
 }

.pre-commit-config.yaml

@@ -1,4 +1,4 @@
-minimum_pre_commit_version: "3.5.0"
+minimum_pre_commit_version: '3.5.0'
 
 repos:
   - repo: https://github.com/JohnnyMorganz/StyLua
@@ -17,7 +17,7 @@ repos:
         files: \.py$
       - id: ruff
         name: ruff (lint imports)
-        args: ["--fix", "--select=I"]
+        args: ['--fix', '--select=I']
         files: \.py$
 
   - repo: local
@@ -26,7 +26,7 @@ repos:
         name: mypy (type check)
         entry: uv run mypy
         language: system
-        args: ["."]
+        args: ['.']
         pass_filenames: false
 
   - repo: https://github.com/pre-commit/mirrors-prettier
@@ -35,4 +35,3 @@ repos:
       - id: prettier
         name: prettier (format markdown)
         files: \.md$
-

.prettierignore

@@ -0,0 +1,8 @@
+.pytest_cache/
+node_modules/
+.venv/
+build/
+dist/
+*.pyc
+__pycache__/
+tests/fixtures/

README.md

@@ -2,22 +2,28 @@
 
 **The definitive competitive programming environment for Neovim**
 
-Scrape problems, run tests, and debug solutions across multiple platforms with zero configuration.
+Scrape problems, run tests, and debug solutions across multiple platforms with
+zero configuration.
 
 https://github.com/user-attachments/assets/50b19481-8e6d-47b4-bebc-15e16c61a9c9
 
 ## Features
 
-- **Multi-platform support**: AtCoder, Codeforces, CSES with consistent interface
+- **Multi-platform support**: AtCoder, Codeforces, CSES with consistent
+  interface
 - **Automatic problem setup**: Scrape test cases and metadata in seconds
-- **Rich test output**: 256 color ANSI support for compiler errors and program output
+- **Dual view modes**: Lightweight I/O view for quick feedback, full panel for
+  detailed analysis
+- **Rich test output**: 256 color ANSI support for compiler errors and program
+  output
 - **Language agnostic**: Works with any language
 - **Diff viewer**: Compare expected vs actual output with 3 diff modes
 
 ## Optional Dependencies
 
 - [uv](https://docs.astral.sh/uv/) for problem scraping
-- GNU [time](https://www.gnu.org/software/time/) and [timeout](https://www.gnu.org/software/coreutils/manual/html_node/timeout-invocation.html)
+- GNU [time](https://www.gnu.org/software/time/) and
+  [timeout](https://www.gnu.org/software/coreutils/manual/html_node/timeout-invocation.html)
 
 ## Quick Start
 
@@ -32,10 +38,11 @@ cp.nvim follows a simple principle: **solve locally, submit remotely**.
    :CP codeforces 1848
    ```
 
-3. **Code and test** with instant feedback and rich diffs
+3. **Code and test** with instant feedback
 
    ```
-   :CP run
+   :CP run        " Quick verdict summary in splits
+   :CP panel      " Detailed analysis with diffs
    ```
 
 4. **Navigate between problems**
@@ -54,7 +61,9 @@ cp.nvim follows a simple principle: **solve locally, submit remotely**.
 :help cp.nvim
 ```
 
-See [my config](https://github.com/barrett-ruth/dots/blob/main/nvim/lua/plugins/cp.lua) for a relatively advanced setup.
+See
+[my config](https://github.com/barrett-ruth/dots/blob/main/nvim/lua/plugins/cp.lua)
+for a relatively advanced setup.
 
 ## Similar Projects
 

doc/cp.nvim.txt

@@ -38,14 +38,23 @@ COMMANDS                                                        *cp-commands*
                                 Example: >
                                     :CP atcoder abc324
 <
-        Action Commands ~
+        View Commands ~
-            :CP run             Toggle run panel for individual test cases.
+            :CP run [n]         Run tests in I/O view (see |cp-io-view|).
-                                Shows per-test results with redesigned
+                                Lightweight split showing test verdicts.
-                                layout for efficient comparison.
+                                Without [n]: runs all tests, shows verdict summary
-
+                                With [n]: runs test n, shows detailed output
-            :CP debug
+                                Examples: >
-                                Same as above but with the debug mode configured
+                                    :CP run          " All tests, verdict list
-                                settings.
+                                    :CP run 3        " Test 3 detail
+<
+            :CP panel [n]       Open full-screen test panel (see |cp-panel|).
+                                Aggregate table with diff modes for detailed analysis.
+                                Optional [n] focuses on specific test.
+                                Example: >
+                                    :CP panel        " All tests with diffs
+                                    :CP panel 2      " Focus on test 2
+<
+            :CP debug [n]       Same as :CP panel but uses debug build configuration.
 
             :CP pick            Launch configured picker for interactive
                                 platform/contest selection.
@@ -145,8 +154,8 @@ Here's an example configuration with lazy.nvim:
         open_url = true,
         debug = false,
         ui = {
-          panel = {
           ansi = true,
+          panel = {
             diff_mode = 'vim',
             max_output_lines = 50,
           },
@@ -238,14 +247,14 @@ run CSES problems with Rust using the single schema:
 
                                                                         *CpUI*
     Fields: ~
+        {ansi}          (boolean, default: true) Enable ANSI color parsing
+                        and highlighting in both I/O view and panel.
         {panel}         (|PanelConfig|) Test panel behavior configuration.
         {diff}          (|DiffConfig|) Diff backend configuration.
         {picker}        (string|nil) 'telescope', 'fzf-lua', or nil.
 
                                                               *cp.PanelConfig*
     Fields: ~
-        {ansi}             (boolean, default: true) Enable ANSI color parsing
-                           and highlighting.
         {diff_mode}        (string, default: "none") Diff backend: "none",
                            "vim", or "git".
         {max_output_lines} (number, default: 50) Maximum lines of test output.
@@ -272,16 +281,32 @@ run CSES problems with Rust using the single schema:
                            function(state: cp.State)
         {setup_code}       (function, optional) Called after source file is opened.
                            function(state: cp.State)
+        {setup_io_input}   (function, optional) Called when I/O input buffer created.
+                           function(bufnr: integer, state: cp.State)
+                           Default: helpers.clearcol (removes line numbers/columns)
+        {setup_io_output}  (function, optional) Called when I/O output buffer created.
+                           function(bufnr: integer, state: cp.State)
+                           Default: helpers.clearcol (removes line numbers/columns)
 
-    Hook functions receive the cp.nvim state object (cp.State). See the state
+    Hook functions receive the cp.nvim state object (|cp.State|). See
-    module documentation (lua/cp/state.lua) for available methods and fields.
+    |lua/cp/state.lua| for available methods and fields.
 
-    Example usage in hook:
+    The I/O buffer hooks are called once when the buffers are first created
+    during problem setup. Use these to customize buffer appearance (e.g.,
+    remove line numbers, set custom options). Access helpers via:
+>lua
+        local helpers = require('cp').helpers
+<
+    Example usage:
 >lua
         hooks = {
           setup_code = function(state)
             print("Setting up " .. state.get_base_name())
             print("Source file: " .. state.get_source_file())
+          end,
+          setup_io_input = function(bufnr, state)
+            -- Custom setup for input buffer
+            vim.api.nvim_set_option_value('number', false, { buf = bufnr })
           end
         }
 <
@@ -333,8 +358,9 @@ Example: Setting up and solving AtCoder contest ABC324
 
 3. Code your solution, then test: >
     :CP run
-<   Navigate with j/k, run specific tests with <enter>
+<   View test verdicts in I/O splits. For detailed analysis:
-    Exit test panel with q or :CP run when done
+    :CP panel
+<   Navigate tests with <c-n>/<c-p>, exit with q
 
 4. Move to next problem: >
     :CP next
@@ -349,6 +375,44 @@ Example: Setting up and solving AtCoder contest ABC324
 
 7. Submit solutions on AtCoder website
 
+==============================================================================
+I/O VIEW                                                          *cp-io-view*
+
+The I/O view provides the main view aggregate view into test input and
+program output. Used time/memory per test case are appended to the output.
+The |cp-panel| offers more fine-grained analysis into each test case.
+
+Access the I/O view with :CP run [n]
+
+Layout ~
+
+The I/O view appears as 30% width splits on the right side: >
+
+    ┌──────────────────────────┬──────────────────────────┐
+    │                          │ Output                   │
+    │                          │ Test 1: AC (42ms, 8MB)   │
+    │                          │ Test 2: AC (38ms, 8MB)   │
+    │   Solution Code          │ Test 3: WA (45ms, 8MB)   │
+    │                          │ Test 4: AC (51ms, 9MB)   │
+    │                          ├──────────────────────────┤
+    │                          │ Input                    │
+    │                          │ 5 3                      │
+    │                          │ 1 2 3 4 5                │
+    │                          │ 2 1                      │
+    │                          │ 10 20                    │
+    └──────────────────────────┴──────────────────────────┘
+<
+Usage ~
+
+    :CP run             Run all tests
+    :CP run 3           Run test 3
+
+Buffer Customization ~
+
+Use the setup_io_input and setup_io_output hooks (see |cp.Hooks|) to customize
+buffer appearance. By default, line numbers and columns are removed via
+helpers.clearcol (see |cp-helpers|).
+
 ==============================================================================
 PICKER INTEGRATION                                                 *cp-picker*
 
@@ -367,11 +431,13 @@ PICKER KEYMAPS                                                  *cp-picker-keys*
         Useful when contest lists are outdated or incomplete
 
 ==============================================================================
-PANEL                                                           *cp-run*
+PANEL                                                               *cp-panel*
 
-The panel provides individual test case debugging. Problem time/memory
+The panel provides full-screen test analysis with diff modes for detailed
-limit constraints are in columns Time/Mem respectively. Used time/memory are
+debugging. Problem time/memory limit constraints are in columns Time/Mem
-in columns Runtime/RSS respectively.
+respectively. Used time/memory are in columns Runtime/RSS respectively.
+
+Access with :CP panel or :CP debug (uses debug build configuration).
 
 Interface ~
 
@@ -502,12 +568,33 @@ Customize highlight groups after your colorscheme loads:
     })
 
 ==============================================================================
-PANEL KEYMAPS                                           *cp-test-keys*
+HELPERS                                                           *cp-helpers*
+
+The helpers module provides utility functions for buffer customization.
+Access via:
+>lua
+    local helpers = require('cp').helpers
+<
+Functions ~
+
+    helpers.clearcol({bufnr})                              *helpers.clearcol*
+        Remove line numbers, columns, and signs from buffer.
+        Sets:
+            • number = false
+            • relativenumber = false
+            • signcolumn = 'no'
+            • statuscolumn = ''
+
+        Parameters: ~
+            {bufnr}  (integer) Buffer handle
+
+==============================================================================
+PANEL KEYMAPS                                                  *cp-panel-keys*
 
 <c-n>   Navigate to next test case
 <c-p>   Navigate to previous test case
 t       Cycle through diff modes: none → git → vim
-q       Exit run panel and restore layout
+q       Exit panel and restore layout
 <c-q>   Exit interactive terminal and restore layout
 
 Diff Modes ~
@@ -537,8 +624,7 @@ cp.nvim creates the following file structure upon problem setup: >
       {problem_id}.run              " Compiled binary
     io/
       {problem_id}.n.cpin           " nth test input
-      {problem_id}.n.cpout          " nth program output
+      {problem_id}.n.cpout          " nth test expected output
-      {problem_id}.expected         " Expected output
 <
 ==============================================================================
 HEALTH CHECK                                                       *cp-health*

lua/cp/commands/init.lua

@@ -16,6 +16,7 @@ local actions = constants.ACTIONS
 ---@field platform? string
 ---@field problem_id? string
 ---@field interactor_cmd? string
+---@field test_index? integer
 
 --- Turn raw args into normalized structure to later dispatch
 ---@param args string[] The raw command-line mode args
@@ -52,6 +53,23 @@ local function parse_command(args)
       else
         return { type = 'action', action = 'interact' }
       end
+    elseif first == 'run' then
+      local test_arg = args[2]
+      if test_arg then
+        local test_index = tonumber(test_arg)
+        if not test_index then
+          return {
+            type = 'error',
+            message = ("Test index '%s' is not a number"):format(test_index),
+          }
+        end
+        if test_index < 1 or test_index ~= math.floor(test_index) then
+          return { type = 'error', message = ("'%s' is not a valid test index"):format(test_index) }
+        end
+        return { type = 'action', action = 'run', test_index = test_index }
+      else
+        return { type = 'action', action = 'run' }
+      end
     else
       return { type = 'action', action = first }
     end
@@ -109,6 +127,8 @@ function M.handle_command(opts)
     if cmd.action == 'interact' then
       ui.toggle_interactive(cmd.interactor_cmd)
     elseif cmd.action == 'run' then
+      ui.run_io_view(cmd.test_index)
+    elseif cmd.action == 'panel' then
       ui.toggle_panel()
     elseif cmd.action == 'debug' then
       ui.toggle_panel({ debug = true })

lua/cp/config.lua

@@ -18,7 +18,6 @@
 ---@field overrides? table<string, CpPlatformOverrides>
 
 ---@class PanelConfig
----@field ansi boolean
 ---@field diff_mode "none"|"vim"|"git"
 ---@field max_output_lines integer
 
@@ -32,8 +31,11 @@
 ---@field before_run? fun(state: cp.State)
 ---@field before_debug? fun(state: cp.State)
 ---@field setup_code? fun(state: cp.State)
+---@field setup_io_input? fun(bufnr: integer, state: cp.State)
+---@field setup_io_output? fun(bufnr: integer, state: cp.State)
 
 ---@class CpUI
+---@field ansi boolean
 ---@field panel PanelConfig
 ---@field diff DiffConfig
 ---@field picker string|nil
@@ -54,6 +56,7 @@
 local M = {}
 
 local constants = require('cp.constants')
+local helpers = require('cp.helpers')
 local utils = require('cp.utils')
 
 -- defaults per the new single schema
@@ -101,12 +104,19 @@ M.defaults = {
       default_language = 'cpp',
     },
   },
-  hooks = { before_run = nil, before_debug = nil, setup_code = nil },
+  hooks = {
+    before_run = nil,
+    before_debug = nil,
+    setup_code = nil,
+    setup_io_input = helpers.clearcol,
+    setup_io_output = helpers.clearcol,
+  },
   debug = false,
   scrapers = constants.PLATFORMS,
   filename = nil,
   ui = {
-    panel = { ansi = true, diff_mode = 'none', max_output_lines = 50 },
+    ansi = true,
+    panel = { diff_mode = 'none', max_output_lines = 50 },
     diff = {
       git = {
         args = { 'diff', '--no-index', '--word-diff=plain', '--word-diff-regex=.', '--no-prefix' },
@@ -229,10 +239,12 @@ function M.setup(user_config)
     before_run = { cfg.hooks.before_run, { 'function', 'nil' }, true },
     before_debug = { cfg.hooks.before_debug, { 'function', 'nil' }, true },
     setup_code = { cfg.hooks.setup_code, { 'function', 'nil' }, true },
+    setup_io_input = { cfg.hooks.setup_io_input, { 'function', 'nil' }, true },
+    setup_io_output = { cfg.hooks.setup_io_output, { 'function', 'nil' }, true },
   })
 
   vim.validate({
-    ansi = { cfg.ui.panel.ansi, 'boolean' },
+    ansi = { cfg.ui.ansi, 'boolean' },
     diff_mode = {
       cfg.ui.panel.diff_mode,
       function(v)

lua/cp/constants.lua

@@ -1,7 +1,7 @@
 local M = {}
 
 M.PLATFORMS = { 'atcoder', 'codeforces', 'cses' }
-M.ACTIONS = { 'run', 'next', 'prev', 'pick', 'cache', 'interact' }
+M.ACTIONS = { 'run', 'panel', 'debug', 'next', 'prev', 'pick', 'cache', 'interact' }
 
 M.PLATFORM_DISPLAY_NAMES = {
   atcoder = 'AtCoder',

lua/cp/helpers.lua

@@ -0,0 +1,13 @@
+local M = {}
+
+---@param bufnr integer
+function M.clearcol(bufnr)
+  for _, win in ipairs(vim.fn.win_findbuf(bufnr)) do
+    vim.wo[win].signcolumn = 'no'
+    vim.wo[win].statuscolumn = ''
+    vim.wo[win].number = false
+    vim.wo[win].relativenumber = false
+  end
+end
+
+return M

lua/cp/init.lua

@@ -1,8 +1,11 @@
 local M = {}
 
 local config_module = require('cp.config')
+local helpers = require('cp.helpers')
 local logger = require('cp.log')
 
+M.helpers = helpers
+
 if vim.fn.has('nvim-0.10.0') == 0 then
   logger.log('Requires nvim-0.10.0+', vim.log.levels.ERROR)
   return {}

lua/cp/runner/run.lua

@@ -122,7 +122,7 @@ local function run_single_test_case(test_case)
   local out = r.stdout or ''
   local highlights = {}
   if out ~= '' then
-    if config.ui.panel.ansi then
+    if config.ui.ansi then
       local parsed = ansi.parse_ansi_text(out)
       out = table.concat(parsed.lines, '\n')
       highlights = parsed.highlights
@@ -224,14 +224,22 @@ function M.run_test_case(index)
   return true
 end
 
+---@param indices? integer[]
 ---@return RanTestCase[]
-function M.run_all_test_cases()
+function M.run_all_test_cases(indices)
-  local results = {}
+  local to_run = indices
+  if not to_run then
+    to_run = {}
     for i = 1, #panel_state.test_cases do
-    M.run_test_case(i)
+      to_run[i] = i
-    results[i] = panel_state.test_cases[i]
     end
-  return results
+  end
+
+  for _, i in ipairs(to_run) do
+    M.run_test_case(i)
+  end
+
+  return panel_state.test_cases
 end
 
 ---@return PanelState
@@ -247,7 +255,7 @@ function M.handle_compilation_failure(output)
   local txt
   local hl = {}
 
-  if config.ui.panel.ansi then
+  if config.ui.ansi then
     local p = ansi.parse_ansi_text(output or '')
     txt = table.concat(p.lines, '\n')
     hl = p.highlights

lua/cp/setup.lua

@@ -3,6 +3,7 @@ local M = {}
 local cache = require('cp.cache')
 local config_module = require('cp.config')
 local constants = require('cp.constants')
+local helpers = require('cp.helpers')
 local logger = require('cp.log')
 local scraper = require('cp.scraper')
 local state = require('cp.state')
@@ -59,6 +60,18 @@ local function start_tests(platform, contest_id, problems)
         ev.memory_mb or 0,
         ev.interactive
       )
+
+      local io_state = state.get_io_view_state()
+      if io_state then
+        local test_cases = cache.get_test_cases(platform, contest_id, state.get_problem_id())
+        local input_lines = {}
+        for _, tc in ipairs(test_cases) do
+          for _, line in ipairs(vim.split(tc.input, '\n')) do
+            table.insert(input_lines, line)
+          end
+        end
+        require('cp.utils').update_buffer_content(io_state.input_buf, input_lines, nil, nil)
+      end
     end)
   end
 end
@@ -152,6 +165,7 @@ end
 function M.setup_problem(problem_id, language)
   local platform = state.get_platform()
   if not platform then
+    logger.log('No platform/contest/problem configured.', vim.log.levels.ERROR)
     return
   end
 
@@ -178,6 +192,9 @@ function M.setup_problem(problem_id, language)
         if ok then
           vim.b[prov.bufnr].cp_setup_done = true
         end
+      elseif not vim.b[prov.bufnr].cp_setup_done then
+        helpers.clearcol(prov.bufnr)
+        vim.b[prov.bufnr].cp_setup_done = true
       end
       cache.set_file_state(
         vim.fn.fnamemodify(source_file, ':p'),
@@ -186,6 +203,7 @@ function M.setup_problem(problem_id, language)
         state.get_problem_id() or '',
         lang
       )
+      require('cp.ui.panel').ensure_io_view()
     end
     state.set_provisional(nil)
     return
@@ -201,6 +219,9 @@ function M.setup_problem(problem_id, language)
       if ok then
         vim.b[bufnr].cp_setup_done = true
       end
+    elseif not vim.b[bufnr].cp_setup_done then
+      helpers.clearcol(bufnr)
+      vim.b[bufnr].cp_setup_done = true
     end
     cache.set_file_state(
       vim.fn.expand('%:p'),
@@ -209,6 +230,7 @@ function M.setup_problem(problem_id, language)
       state.get_problem_id() or '',
       lang
     )
+    require('cp.ui.panel').ensure_io_view()
   end)
 end
 
@@ -247,7 +269,11 @@ function M.navigate_problem(direction)
     return
   end
 
+  local active_panel = state.get_active_panel()
+  if active_panel == 'run' then
     require('cp.ui.panel').disable()
+  end
+
   M.setup_contest(platform, contest_id, problems[new_index].id)
 end
 

lua/cp/state.lua

@@ -3,9 +3,15 @@
 ---@field platform string
 ---@field contest_id string
 ---@field language string
----@field requested_problem_id string|nil
+---@field requested_problem_id string?
 ---@field token integer
 
+---@class cp.IoViewState
+---@field output_buf integer
+---@field input_buf integer
+---@field output_win integer
+---@field input_win integer
+
 ---@class cp.State
 ---@field get_platform fun(): string?
 ---@field set_platform fun(platform: string)
@@ -21,8 +27,12 @@
 ---@field get_input_file fun(): string?
 ---@field get_output_file fun(): string?
 ---@field get_expected_file fun(): string?
----@field get_provisional fun(): cp.ProvisionalState|nil
+---@field get_provisional fun(): cp.ProvisionalState?
----@field set_provisional fun(p: cp.ProvisionalState|nil)
+---@field set_provisional fun(p: cp.ProvisionalState?)
+---@field get_saved_session fun(): string?
+---@field set_saved_session fun(path: string?)
+---@field get_io_view_state fun(): cp.IoViewState?
+---@field set_io_view_state fun(s: cp.IoViewState?)
 
 local M = {}
 
@@ -36,9 +46,10 @@ local state = {
   active_panel = nil,
   provisional = nil,
   solution_win = nil,
+  io_view_state = nil,
 }
 
----@return string|nil
+---@return string?
 function M.get_platform()
   return state.platform
 end
@@ -48,7 +59,7 @@ function M.set_platform(platform)
   state.platform = platform
 end
 
----@return string|nil
+---@return string?
 function M.get_contest_id()
   return state.contest_id
 end
@@ -58,7 +69,7 @@ function M.set_contest_id(contest_id)
   state.contest_id = contest_id
 end
 
----@return string|nil
+---@return string?
 function M.get_problem_id()
   return state.problem_id
 end
@@ -68,7 +79,7 @@ function M.set_problem_id(problem_id)
   state.problem_id = problem_id
 end
 
----@return string|nil
+---@return string?
 function M.get_base_name()
   local platform, contest_id, problem_id = M.get_platform(), M.get_contest_id(), M.get_problem_id()
   if not platform or not contest_id or not problem_id then
@@ -86,7 +97,7 @@ function M.get_base_name()
 end
 
 ---@param language? string
----@return string|nil
+---@return string?
 function M.get_source_file(language)
   local base_name = M.get_base_name()
   if not base_name or not M.get_platform() then
@@ -110,46 +121,46 @@ function M.get_source_file(language)
   return base_name .. '.' .. eff.extension
 end
 
----@return string|nil
+---@return string?
 function M.get_binary_file()
   local base_name = M.get_base_name()
   return base_name and ('build/%s.run'):format(base_name) or nil
 end
 
----@return string|nil
+---@return string?
 function M.get_input_file()
   local base_name = M.get_base_name()
   return base_name and ('io/%s.cpin'):format(base_name) or nil
 end
 
----@return string|nil
+---@return string?
 function M.get_output_file()
   local base_name = M.get_base_name()
   return base_name and ('io/%s.cpout'):format(base_name) or nil
 end
 
----@return string|nil
+---@return string?
 function M.get_expected_file()
   local base_name = M.get_base_name()
   return base_name and ('io/%s.expected'):format(base_name) or nil
 end
 
----@return string|nil
+---@return string?
 function M.get_active_panel()
   return state.active_panel
 end
 
----@param panel string|nil
+---@param panel string?
 function M.set_active_panel(panel)
   state.active_panel = panel
 end
 
----@return cp.ProvisionalState|nil
+---@return cp.ProvisionalState?
 function M.get_provisional()
   return state.provisional
 end
 
----@param p cp.ProvisionalState|nil
+---@param p cp.ProvisionalState?
 function M.set_provisional(p)
   state.provisional = p
 end
@@ -167,6 +178,38 @@ function M.set_solution_win(win)
   state.solution_win = win
 end
 
+---@return cp.IoViewState?
+function M.get_io_view_state()
+  if not state.io_view_state then
+    return nil
+  end
+  local s = state.io_view_state
+  if
+    vim.api.nvim_buf_is_valid(s.output_buf)
+    and vim.api.nvim_buf_is_valid(s.input_buf)
+    and vim.api.nvim_win_is_valid(s.output_win)
+    and vim.api.nvim_win_is_valid(s.input_win)
+  then
+    return s
+  end
+  return nil
+end
+
+---@param s cp.IoViewState?
+function M.set_io_view_state(s)
+  state.io_view_state = s
+end
+
+---@return string?
+function M.get_saved_session()
+  return state.saved_session
+end
+
+---@param path string?
+function M.set_saved_session(path)
+  state.saved_session = path
+end
+
 M._state = state
 
 return M

lua/cp/ui/ansi.lua

@@ -321,6 +321,25 @@ function M.setup_highlight_groups()
   vim.api.nvim_set_hl(0, 'CpAnsiBold', { bold = true })
   vim.api.nvim_set_hl(0, 'CpAnsiItalic', { italic = true })
   vim.api.nvim_set_hl(0, 'CpAnsiBoldItalic', { bold = true, italic = true })
+
+  for _, combo in ipairs(combinations) do
+    for color_name, _ in pairs(color_map) do
+      local parts = { 'CpAnsi' }
+      if combo.bold then
+        table.insert(parts, 'Bold')
+      end
+      if combo.italic then
+        table.insert(parts, 'Italic')
+      end
+      table.insert(parts, color_name)
+      local hl_name = table.concat(parts)
+      dyn_hl_cache[hl_name] = true
+    end
+  end
+
+  dyn_hl_cache['CpAnsiBold'] = true
+  dyn_hl_cache['CpAnsiItalic'] = true
+  dyn_hl_cache['CpAnsiBoldItalic'] = true
 end
 
 ---@param text string

lua/cp/ui/layouts.lua

@@ -1,10 +1,13 @@
 local M = {}
 
+local helpers = require('cp.helpers')
 local utils = require('cp.utils')
 
 local function create_none_diff_layout(parent_win, expected_content, actual_content)
   local expected_buf = utils.create_buffer_with_options()
   local actual_buf = utils.create_buffer_with_options()
+  helpers.clearcol(expected_buf)
+  helpers.clearcol(actual_buf)
 
   vim.api.nvim_set_current_win(parent_win)
   vim.cmd.split()
@@ -42,6 +45,8 @@ end
 local function create_vim_diff_layout(parent_win, expected_content, actual_content)
   local expected_buf = utils.create_buffer_with_options()
   local actual_buf = utils.create_buffer_with_options()
+  helpers.clearcol(expected_buf)
+  helpers.clearcol(actual_buf)
 
   vim.api.nvim_set_current_win(parent_win)
   vim.cmd.split()
@@ -89,6 +94,7 @@ end
 
 local function create_git_diff_layout(parent_win, expected_content, actual_content)
   local diff_buf = utils.create_buffer_with_options()
+  helpers.clearcol(diff_buf)
 
   vim.api.nvim_set_current_win(parent_win)
   vim.cmd.split()

lua/cp/ui/panel.lua

@@ -3,8 +3,9 @@ local M = {}
 ---@class PanelOpts
 ---@field debug? boolean
 
+local cache = require('cp.cache')
 local config_module = require('cp.config')
-local constants = require('cp.constants')
+local helpers = require('cp.helpers')
 local layouts = require('cp.ui.layouts')
 local logger = require('cp.log')
 local state = require('cp.state')
@@ -52,38 +53,24 @@ function M.toggle_interactive(interactor_cmd)
     return
   end
 
-  local platform, contest_id = state.get_platform(), state.get_contest_id()
+  local platform, contest_id, problem_id =
-  if not platform then
+    state.get_platform(), state.get_contest_id(), state.get_problem_id()
-    logger.log('No platform configured.', vim.log.levels.ERROR)
+  if not platform or not contest_id or not problem_id then
-    return
-  end
-  if not contest_id then
     logger.log(
-      ("No contest %s configured for platform '%s'."):format(
+      'No platform/contest/problem configured. Use :CP <platform> <contest> [...] first.',
-        contest_id,
-        constants.PLATFORM_DISPLAY_NAMES[platform]
-      ),
       vim.log.levels.ERROR
     )
     return
   end
 
-  local problem_id = state.get_problem_id()
-  if not problem_id then
-    logger.log('No problem is active.', vim.log.levels.ERROR)
-    return
-  end
-
-  local cache = require('cp.cache')
   cache.load()
   local contest_data = cache.get_contest_data(platform, contest_id)
   if
     not contest_data
     or not contest_data.index_map
-    or not contest_data.problems[contest_data.index_map[problem_id]]
+    or contest_data.problems[contest_data.index_map[problem_id]].interactive
-    or not contest_data.problems[contest_data.index_map[problem_id]].interactive
   then
-    logger.log('This problem is not interactive. Use :CP run.', vim.log.levels.ERROR)
+    logger.log('This problem is interactive. Use :CP {run,panel}.', vim.log.levels.ERROR)
     return
   end
 
@@ -92,9 +79,10 @@ function M.toggle_interactive(interactor_cmd)
   vim.cmd('silent only')
 
   local execute = require('cp.runner.execute')
+  local run = require('cp.runner.run')
   local compile_result = execute.compile_problem()
   if not compile_result.success then
-    require('cp.runner.run').handle_compilation_failure(compile_result.output)
+    run.handle_compilation_failure(compile_result.output)
     return
   end
 
@@ -204,6 +192,230 @@ function M.toggle_interactive(interactor_cmd)
   state.set_active_panel('interactive')
 end
 
+function M.ensure_io_view()
+  local platform, contest_id, problem_id =
+    state.get_platform(), state.get_contest_id(), state.get_problem_id()
+  if not platform or not contest_id or not problem_id then
+    logger.log(
+      'No platform/contest/problem configured. Use :CP <platform> <contest> [...] first.',
+      vim.log.levels.ERROR
+    )
+    return
+  end
+
+  cache.load()
+  local contest_data = cache.get_contest_data(platform, contest_id)
+  if
+    contest_data
+    and contest_data.index_map
+    and contest_data.problems[contest_data.index_map[problem_id]].interactive
+  then
+    logger.log('No platform configured.', vim.log.levels.ERROR)
+    return
+  end
+
+  local solution_win = state.get_solution_win()
+  local io_state = state.get_io_view_state()
+  local output_buf, input_buf, output_win, input_win
+
+  if io_state then
+    output_buf = io_state.output_buf
+    input_buf = io_state.input_buf
+    output_win = io_state.output_win
+    input_win = io_state.input_win
+  else
+    vim.api.nvim_set_current_win(solution_win)
+
+    vim.cmd.vsplit()
+    output_win = vim.api.nvim_get_current_win()
+    local width = math.floor(vim.o.columns * 0.3)
+    vim.api.nvim_win_set_width(output_win, width)
+    output_buf = utils.create_buffer_with_options()
+    vim.api.nvim_win_set_buf(output_win, output_buf)
+
+    vim.cmd.split()
+    input_win = vim.api.nvim_get_current_win()
+    input_buf = utils.create_buffer_with_options()
+    vim.api.nvim_win_set_buf(input_win, input_buf)
+
+    state.set_io_view_state({
+      output_buf = output_buf,
+      input_buf = input_buf,
+      output_win = output_win,
+      input_win = input_win,
+    })
+
+    local config = config_module.get_config()
+    if config.hooks and config.hooks.setup_io_output then
+      pcall(config.hooks.setup_io_output, output_buf, state)
+    end
+
+    if config.hooks and config.hooks.setup_io_input then
+      pcall(config.hooks.setup_io_input, input_buf, state)
+    end
+  end
+
+  utils.update_buffer_content(input_buf, {})
+  utils.update_buffer_content(output_buf, {})
+
+  local test_cases = cache.get_test_cases(platform, contest_id, problem_id)
+  if test_cases and #test_cases > 0 then
+    local input_lines = {}
+    for _, tc in ipairs(test_cases) do
+      for _, line in ipairs(vim.split(tc.input, '\n')) do
+        table.insert(input_lines, line)
+      end
+    end
+    utils.update_buffer_content(input_buf, input_lines, nil, nil)
+  end
+
+  vim.api.nvim_set_current_win(solution_win)
+end
+
+function M.run_io_view(test_index)
+  local platform, contest_id, problem_id =
+    state.get_platform(), state.get_contest_id(), state.get_problem_id()
+  if not platform or not contest_id or not problem_id then
+    logger.log(
+      'No platform/contest/problem configured. Use :CP <platform> <contest> [...] first.',
+      vim.log.levels.ERROR
+    )
+    return
+  end
+
+  cache.load()
+  local contest_data = cache.get_contest_data(platform, contest_id)
+  if
+    not contest_data
+    or not contest_data.index_map
+    or contest_data.problems[contest_data.index_map[problem_id]].interactive
+  then
+    logger.log('This problem is interactive. Use :CP {run,panel}.', vim.log.levels.ERROR)
+    return
+  end
+
+  M.ensure_io_view()
+
+  local run = require('cp.runner.run')
+  if not run.load_test_cases() then
+    logger.log('No test cases available', vim.log.levels.ERROR)
+    return
+  end
+
+  local test_state = run.get_panel_state()
+  local test_indices = {}
+
+  if test_index then
+    if test_index < 1 or test_index > #test_state.test_cases then
+      logger.log(
+        string.format(
+          'Test %d does not exist (only %d tests available)',
+          test_index,
+          #test_state.test_cases
+        ),
+        vim.log.levels.WARN
+      )
+      return
+    end
+    test_indices = { test_index }
+  else
+    for i = 1, #test_state.test_cases do
+      test_indices[i] = i
+    end
+  end
+
+  local io_state = state.get_io_view_state()
+  if not io_state then
+    return
+  end
+
+  local config = config_module.get_config()
+
+  if config.ui.ansi then
+    require('cp.ui.ansi').setup_highlight_groups()
+  end
+
+  local execute = require('cp.runner.execute')
+  local compile_result = execute.compile_problem()
+  if not compile_result.success then
+    local ansi = require('cp.ui.ansi')
+    local output = compile_result.output or ''
+    local lines, highlights
+
+    if config.ui.ansi then
+      local parsed = ansi.parse_ansi_text(output)
+      lines = parsed.lines
+      highlights = parsed.highlights
+    else
+      lines = vim.split(output:gsub('\027%[[%d;]*[a-zA-Z]', ''), '\n')
+      highlights = {}
+    end
+
+    local ns = vim.api.nvim_create_namespace('cp_io_view_compile_error')
+    utils.update_buffer_content(io_state.output_buf, lines, highlights, ns)
+    return
+  end
+
+  run.run_all_test_cases(test_indices)
+
+  local input_lines = {}
+  for _, idx in ipairs(test_indices) do
+    local tc = test_state.test_cases[idx]
+    for _, line in ipairs(vim.split(tc.input, '\n')) do
+      table.insert(input_lines, line)
+    end
+  end
+  utils.update_buffer_content(io_state.input_buf, input_lines, nil, nil)
+
+  local run_render = require('cp.runner.run_render')
+  run_render.setup_highlights()
+
+  if #test_indices == 1 then
+    local idx = test_indices[1]
+    local tc = test_state.test_cases[idx]
+    local status = run_render.get_status_info(tc)
+
+    local output_lines = {}
+    if tc.actual then
+      for _, line in ipairs(vim.split(tc.actual, '\n', { plain = true, trimempty = false })) do
+        table.insert(output_lines, line)
+      end
+    end
+
+    table.insert(output_lines, '')
+    local time = tc.time_ms and string.format('%.2fms', tc.time_ms) or '—'
+    local code = tc.code and tostring(tc.code) or '—'
+    table.insert(output_lines, string.format('--- %s: %s | Exit: %s ---', status.text, time, code))
+
+    local highlights = tc.actual_highlights or {}
+    local ns = vim.api.nvim_create_namespace('cp_io_view_output')
+    utils.update_buffer_content(io_state.output_buf, output_lines, highlights, ns)
+  else
+    local verdict_lines = {}
+    local verdict_highlights = {}
+    for _, idx in ipairs(test_indices) do
+      local tc = test_state.test_cases[idx]
+      local status = run_render.get_status_info(tc)
+      local time = tc.time_ms and string.format('%.2f', tc.time_ms) or '—'
+      local mem = tc.rss_mb and string.format('%.0f', tc.rss_mb) or '—'
+      local line = string.format('Test %d: %s (%sms, %sMB)', idx, status.text, time, mem)
+      table.insert(verdict_lines, line)
+      local status_pos = line:find(status.text, 1, true)
+      if status_pos then
+        table.insert(verdict_highlights, {
+          line = #verdict_lines - 1,
+          col_start = status_pos - 1,
+          col_end = status_pos - 1 + #status.text,
+          highlight_group = status.highlight_group,
+        })
+      end
+    end
+
+    local verdict_ns = vim.api.nvim_create_namespace('cp_io_view_verdict')
+    utils.update_buffer_content(io_state.output_buf, verdict_lines, verdict_highlights, verdict_ns)
+  end
+end
+
 ---@param panel_opts? PanelOpts
 function M.toggle_panel(panel_opts)
   if state.get_active_panel() == 'run' then
@@ -212,12 +424,14 @@ function M.toggle_panel(panel_opts)
       current_diff_layout = nil
       current_mode = nil
     end
-    if state.saved_session then
+    local saved = state.get_saved_session()
-      vim.cmd(('source %s'):format(state.saved_session))
+    if saved then
-      vim.fn.delete(state.saved_session)
+      vim.cmd(('source %s'):format(saved))
-      state.saved_session = nil
+      vim.fn.delete(saved)
+      state.set_saved_session(nil)
     end
     state.set_active_panel(nil)
+    M.ensure_io_view()
     return
   end
 
@@ -228,26 +442,14 @@ function M.toggle_panel(panel_opts)
 
   local platform, contest_id = state.get_platform(), state.get_contest_id()
 
-  if not platform then
+  if not platform or not contest_id then
     logger.log(
-      'No platform configured. Use :CP <platform> <contest> [...] first.',
+      'No platform/contest configured. Use :CP <platform> <contest> [...] first.',
       vim.log.levels.ERROR
     )
     return
   end
 
-  if not contest_id then
-    logger.log(
-      ("No contest '%s' configured for platform '%s'."):format(
-        contest_id,
-        constants.PLATFORM_DISPLAY_NAMES[platform]
-      ),
-      vim.log.levels.ERROR
-    )
-    return
-  end
-
-  local cache = require('cp.cache')
   cache.load()
   local contest_data = cache.get_contest_data(platform, contest_id)
   if
@@ -260,6 +462,7 @@ function M.toggle_panel(panel_opts)
 
   local config = config_module.get_config()
   local run = require('cp.runner.run')
+  local run_render = require('cp.runner.run_render')
   local input_file = state.get_input_file()
   logger.log(('run panel: checking test cases for %s'):format(input_file or 'none'))
 
@@ -268,11 +471,24 @@ function M.toggle_panel(panel_opts)
     return
   end
 
-  state.saved_session = vim.fn.tempname()
+  local io_state = state.get_io_view_state()
-  vim.cmd(('mksession! %s'):format(state.saved_session))
+  if io_state then
+    if vim.api.nvim_win_is_valid(io_state.output_win) then
+      vim.api.nvim_win_close(io_state.output_win, true)
+    end
+    if vim.api.nvim_win_is_valid(io_state.input_win) then
+      vim.api.nvim_win_close(io_state.input_win, true)
+    end
+    state.set_io_view_state(nil)
+  end
+
+  local session_file = vim.fn.tempname()
+  state.set_saved_session(session_file)
+  vim.cmd(('mksession! %s'):format(session_file))
   vim.cmd('silent only')
 
   local tab_buf = utils.create_buffer_with_options()
+  helpers.clearcol(tab_buf)
   local main_win = vim.api.nvim_get_current_win()
   vim.api.nvim_win_set_buf(main_win, tab_buf)
   vim.api.nvim_set_option_value('filetype', 'cp', { buf = tab_buf })
@@ -298,7 +514,6 @@ function M.toggle_panel(panel_opts)
     if not test_buffers.tab_buf or not vim.api.nvim_buf_is_valid(test_buffers.tab_buf) then
       return
     end
-    local run_render = require('cp.runner.run_render')
     run_render.setup_highlights()
     local test_state = run.get_panel_state()
     local tab_lines, tab_highlights = run_render.render_test_list(test_state)
@@ -368,9 +583,8 @@ function M.toggle_panel(panel_opts)
   refresh_panel()
 
   vim.schedule(function()
-    if config.ui.panel.ansi then
+    if config.ui.ansi then
-      local ansi = require('cp.ui.ansi')
+      require('cp.ui.ansi').setup_highlight_groups()
-      ansi.setup_highlight_groups()
     end
     if current_diff_layout then
       update_diff_panes()

lua/cp/utils.lua

@@ -125,6 +125,10 @@ function M.create_buffer_with_options(filetype)
   return buf
 end
 
+---@param bufnr integer
+---@param lines string[]
+---@param highlights? Highlight[]
+---@param namespace? integer
 function M.update_buffer_content(bufnr, lines, highlights, namespace)
   local was_readonly = vim.api.nvim_get_option_value('readonly', { buf = bufnr })
 

scrapers/cses.py

@@ -72,24 +72,24 @@ async def fetch_text(client: httpx.AsyncClient, path: str) -> str:
 
 
 CATEGORY_BLOCK_RE = re.compile(
-    r'<h2>(?P<cat>[^<]+)</h2>\s*<ul class="task-list">(?P<body>.*?)</ul>',
+    r'<h2>(?P<cat>[^<]+)</h2>\s*<ul\s+class="task-list">(?P<body>.*?)</ul>',
     re.DOTALL,
 )
 TASK_LINK_RE = re.compile(
-    r'<li class="task"><a href="/problemset/task/(?P<id>\d+)/?">(?P<title>[^<]+)</a>',
+    r'<li\s+class="task">\s*<a\s+href="/problemset/task/(?P<id>\d+)/?">(?P<title>[^<]+)</a\s*>',
     re.DOTALL,
 )
 
 TITLE_RE = re.compile(
-    r'<div class="title-block">.*?<h1>(?P<title>[^<]+)</h1>', re.DOTALL
+    r'<div\s+class="title-block">.*?<h1>(?P<title>[^<]+)</h1>', re.DOTALL
 )
-TIME_RE = re.compile(r"<li><b>Time limit:</b>\s*([0-9.]+)\s*s</li>")
+TIME_RE = re.compile(r"<li>\s*<b>Time limit:</b>\s*([0-9.]+)\s*s\s*</li>")
-MEM_RE = re.compile(r"<li><b>Memory limit:</b>\s*(\d+)\s*MB</li>")
+MEM_RE = re.compile(r"<li>\s*<b>Memory limit:</b>\s*(\d+)\s*MB\s*</li>")
 SIDEBAR_CAT_RE = re.compile(
-    r'<div class="nav sidebar">.*?<h4>(?P<cat>[^<]+)</h4>', re.DOTALL
+    r'<div\s+class="nav sidebar">.*?<h4>(?P<cat>[^<]+)</h4>', re.DOTALL
 )
 
-MD_BLOCK_RE = re.compile(r'<div class="md">(.*?)</div>', re.DOTALL | re.IGNORECASE)
+MD_BLOCK_RE = re.compile(r'<div\s+class="md">(.*?)</div>', re.DOTALL | re.IGNORECASE)
 EXAMPLE_SECTION_RE = re.compile(
     r"<h[1-6][^>]*>\s*example[s]?:?\s*</h[1-6]>\s*(?P<section>.*?)(?=<h[1-6][^>]*>|$)",
     re.DOTALL | re.IGNORECASE,