README.md

@@ -10,14 +10,14 @@ https://github.com/user-attachments/assets/e81d8dfb-578f-4a79-9989-210164fc0148
 ## Features
 
 - **Multi-platform support**: AtCoder, CodeChef, Codeforces, USACO, CSES, Kattis
-- **Online Judge Integration**: Submit problems and view contest standings
+- **Automatic problem setup**: Scrape test cases and metadata in seconds
-- **Live Contest Support**: Participate in real-time contests
+- **Dual view modes**: Lightweight I/O view for quick feedback, full panel for
-- **Automatic setup**: Scrape test cases and metadata in seconds
+  detailed analysis
-- **Streamlined Editing**: Configure coding view, edit test cases, stress-test
+- **Test case management**: Quickly view, edit, add, & remove test cases
-  solutions, run interactive problems, and more
+- **Rich test output**: 256 color ANSI support for compiler errors and program
-- **Rich output**: 256 color ANSI support for compiler errors and program output
+  output
-- **Language agnosticism**: Configure with any language
+- **Language agnostic**: Works with any language
-- **Security**: Passwords go untampered
+- **Diff viewer**: Compare expected vs actual output with 3 diff modes
 
 ## Installation
 
@@ -37,16 +37,15 @@ luarocks install cp.nvim
 
 ## Quick Start
 
-1. Find a contest:
+cp.nvim follows a simple principle: **solve locally, submit remotely**.
+
+### Basic Usage
+
+1. Find a contest or problem
+2. Set up contests locally
 
    ```
-:CP pick
+   :CP codeforces 1848
-```
-
-2. View the problem:
-
-```
-:CP open
    ```
 
 3. Code and test
@@ -70,17 +69,7 @@ luarocks install cp.nvim
 :CP panel --debug
 ```
 
-6. Submit:
+5. Submit on the original website
-
-```
-:CP submit
-```
-
-7. View contest standings:
-
-```
-:CP open standings
-```
 
 ## Documentation
 
@@ -89,7 +78,7 @@ luarocks install cp.nvim
 ```
 
 See
-[my config](https://github.com/barrettruth/nix/blob/5d0ede3668eb7f5ad2b4475267fc0458f9fa4527/config/nvim/lua/plugins/dev.lua#L165)
+[my config](https://github.com/barrettruth/dots/blob/main/.config/nvim/lua/plugins/cp.lua)
 for the setup in the video shown above.
 
 ## Motivation

doc/cp.nvim.txt

@@ -49,8 +49,7 @@ REQUIREMENTS                                                 *cp-requirements*
 
 - Neovim 0.10.0+
 - Unix-like operating system
-- (Optional) git 1.7.9+ (credential storage)
+- uv package manager (https://docs.astral.sh/uv/)
-- (Optional) uv package manager (https://docs.astral.sh/uv/)
 
 ==============================================================================
 SETUP                                                              *cp-setup*
@@ -999,15 +998,8 @@ CREDENTIALS                                                   *cp-credentials*
 
 Manage stored login credentials for platform submission.
 
-Credentials are stored via git-credential(1), using whatever credential
+Credentials are stored under _credentials in the main cache file
-helper is configured in your git config (macOS Keychain, libsecret,
+(stdpath('data')/cp-nvim.json). Use :CP cache read to inspect them.
-credential-store, etc.). Git is required. Cookie files
-(~/.cache/cp-nvim/cookies.json) are unaffected.
-
-To inspect stored credentials:
->sh
-    printf 'protocol=https\nhost=cses.fi\n\n' | git credential fill
-<
 
 :CP login [platform]
         Set or update credentials for a platform. Prompts for username

lua/cp/cache.lua

@@ -42,10 +42,13 @@
 
 local M = {}
 
+local CACHE_VERSION = 2
+
 local cache_file = vim.fn.stdpath('data') .. '/cp-nvim.json'
 local cache_data = {}
 local loaded = false
 
+--- Load the cache from disk if not done already
 ---@return nil
 function M.load()
   if loaded then
@@ -53,11 +56,8 @@ function M.load()
   end
 
   if vim.fn.filereadable(cache_file) == 0 then
-    vim.fn.mkdir(vim.fn.fnamemodify(cache_file, ':h'), 'p')
+    vim.fn.writefile({}, cache_file)
-    local tmpfile = vim.fn.tempname()
+    vim.fn.setfperm(cache_file, 'rw-------')
-    vim.fn.writefile({}, tmpfile)
-    vim.fn.setfperm(tmpfile, 'rw-------')
-    vim.uv.fs_rename(tmpfile, cache_file)
     loaded = true
     return
   end
@@ -70,7 +70,26 @@ function M.load()
   end
 
   local ok, decoded = pcall(vim.json.decode, table.concat(content, '\n'))
-  if ok and type(decoded) == 'table' then
+  if not ok then
+    cache_data = {}
+    M.save()
+    loaded = true
+    return
+  end
+
+  if decoded._version == 1 then
+    local old_creds = decoded._credentials
+    decoded._credentials = nil
+    if old_creds then
+      for platform, creds in pairs(old_creds) do
+        decoded[platform] = decoded[platform] or {}
+        decoded[platform]._credentials = creds
+      end
+    end
+    decoded._version = CACHE_VERSION
+    cache_data = decoded
+    M.save()
+  elseif decoded._version == CACHE_VERSION then
     cache_data = decoded
   else
     cache_data = {}
@@ -79,16 +98,17 @@ function M.load()
   loaded = true
 end
 
+--- Save the cache to disk, overwriting existing contents
 ---@return nil
 function M.save()
   vim.schedule(function()
     vim.fn.mkdir(vim.fn.fnamemodify(cache_file, ':h'), 'p')
+
+    cache_data._version = CACHE_VERSION
     local encoded = vim.json.encode(cache_data)
     local lines = vim.split(encoded, '\n')
-    local tmpfile = vim.fn.tempname()
+    vim.fn.writefile(lines, cache_file)
-    vim.fn.writefile(lines, tmpfile)
+    vim.fn.setfperm(cache_file, 'rw-------')
-    vim.fn.setfperm(tmpfile, 'rw-------')
-    vim.uv.fs_rename(tmpfile, cache_file)
   end)
 end
 
@@ -425,6 +445,31 @@ function M.get_contest_display_name(platform, contest_id)
   return cache_data[platform][contest_id].display_name
 end
 
+---@param platform string
+---@return table?
+function M.get_credentials(platform)
+  if not cache_data[platform] then
+    return nil
+  end
+  return cache_data[platform]._credentials
+end
+
+---@param platform string
+---@param creds table
+function M.set_credentials(platform, creds)
+  cache_data[platform] = cache_data[platform] or {}
+  cache_data[platform]._credentials = creds
+  M.save()
+end
+
+---@param platform string
+function M.clear_credentials(platform)
+  if cache_data[platform] then
+    cache_data[platform]._credentials = nil
+  end
+  M.save()
+end
+
 ---@return nil
 function M.clear_all()
   cache_data = {}

lua/cp/credentials.lua

@@ -1,7 +1,7 @@
 local M = {}
 
+local cache = require('cp.cache')
 local constants = require('cp.constants')
-local git_credential = require('cp.git_credential')
 local logger = require('cp.log')
 local state = require('cp.state')
 
@@ -40,14 +40,14 @@ local function prompt_and_login(platform, display)
       end, function(result)
         vim.schedule(function()
           if result.success then
-            git_credential.store(platform, credentials)
+            cache.set_credentials(platform, credentials)
             logger.log(
               display .. ' login successful',
               { level = vim.log.levels.INFO, override = true }
             )
           else
             local err = result.error or 'unknown error'
-            git_credential.reject(platform, credentials)
+            cache.clear_credentials(platform)
             logger.log(
               display .. ' login failed: ' .. (constants.LOGIN_ERRORS[err] or err),
               { level = vim.log.levels.ERROR }
@@ -71,17 +71,10 @@ function M.login(platform)
     return
   end
 
-  if not git_credential.has_helper() then
-    logger.log(
-      'No git credential helper configured. See :help cp-credentials',
-      { level = vim.log.levels.ERROR }
-    )
-    return
-  end
-
   local display = constants.PLATFORM_DISPLAY_NAMES[platform] or platform
 
-  local existing = git_credential.get(platform) or {}
+  cache.load()
+  local existing = cache.get_credentials(platform) or {}
 
   if existing.username and existing.password then
     local scraper = require('cp.scraper')
@@ -98,7 +91,7 @@ function M.login(platform)
             { level = vim.log.levels.INFO, override = true }
           )
         else
-          git_credential.reject(platform, existing)
+          cache.clear_credentials(platform)
           prompt_and_login(platform, display)
         end
       end)
@@ -119,28 +112,16 @@ function M.logout(platform)
     )
     return
   end
-  if not git_credential.has_helper() then
-    logger.log(
-      'No git credential helper configured. See :help cp-credentials',
-      { level = vim.log.levels.ERROR }
-    )
-    return
-  end
-
   local display = constants.PLATFORM_DISPLAY_NAMES[platform] or platform
-  local existing = git_credential.get(platform)
+  cache.load()
-  if existing then
+  cache.clear_credentials(platform)
-    git_credential.reject(platform, existing)
-  end
   local cookie_file = constants.COOKIE_FILE
   if vim.fn.filereadable(cookie_file) == 1 then
     local ok, data = pcall(vim.fn.json_decode, vim.fn.readfile(cookie_file, 'b'))
     if ok and type(data) == 'table' then
       data[platform] = nil
-      local tmpfile = vim.fn.tempname()
+      vim.fn.writefile({ vim.fn.json_encode(data) }, cookie_file)
-      vim.fn.writefile({ vim.fn.json_encode(data) }, tmpfile)
+      vim.fn.setfperm(cookie_file, 'rw-------')
-      vim.fn.setfperm(tmpfile, 'rw-------')
-      vim.uv.fs_rename(tmpfile, cookie_file)
     end
   end
   logger.log(display .. ' credentials cleared', { level = vim.log.levels.INFO, override = true })

lua/cp/git_credential.lua

@@ -1,107 +0,0 @@
----@class cp.Credentials
----@field username string
----@field password string
-
-local M = {}
-
-local HOSTS = {
-  atcoder = 'atcoder.jp',
-  codechef = 'www.codechef.com',
-  codeforces = 'codeforces.com',
-  cses = 'cses.fi',
-  kattis = 'open.kattis.com',
-  usaco = 'usaco.org',
-}
-
-local _helper_checked = false
-local _helper_ok = false
-
----@return boolean
-function M.has_helper()
-  if not _helper_checked then
-    local r = vim
-      .system({ 'git', 'config', 'credential.helper' }, { text = true, timeout = 5000 })
-      :wait()
-    _helper_ok = r.code == 0 and r.stdout ~= nil and vim.trim(r.stdout) ~= ''
-    _helper_checked = true
-  end
-  return _helper_ok
-end
-
----@param host string
----@param extra? table<string, string>
----@return string
-local function _build_input(host, extra)
-  local lines = { 'protocol=https', 'host=' .. host }
-  if extra then
-    for k, v in pairs(extra) do
-      table.insert(lines, k .. '=' .. v)
-    end
-  end
-  table.insert(lines, '')
-  table.insert(lines, '')
-  return table.concat(lines, '\n')
-end
-
----@param stdout string
----@return table<string, string>
-local function _parse_output(stdout)
-  local result = {}
-  for line in stdout:gmatch('[^\n]+') do
-    local k, v = line:match('^(%S+)=(.+)$')
-    if k and v then
-      result[k] = v
-    end
-  end
-  return result
-end
-
----@param platform string
----@return cp.Credentials?
-function M.get(platform)
-  local host = HOSTS[platform]
-  if not host then
-    return nil
-  end
-
-  local input = _build_input(host)
-  local obj = vim
-    .system({ 'git', 'credential', 'fill' }, { stdin = input, text = true, timeout = 5000 })
-    :wait()
-  if obj.code ~= 0 then
-    return nil
-  end
-
-  local parsed = _parse_output(obj.stdout or '')
-  if not parsed.username or not parsed.password then
-    return nil
-  end
-
-  return { username = parsed.username, password = parsed.password }
-end
-
----@param platform string
----@param creds cp.Credentials
-function M.store(platform, creds)
-  local host = HOSTS[platform]
-  if not host then
-    return
-  end
-
-  local input = _build_input(host, { username = creds.username, password = creds.password })
-  vim.system({ 'git', 'credential', 'approve' }, { stdin = input, text = true }):wait()
-end
-
----@param platform string
----@param creds cp.Credentials
-function M.reject(platform, creds)
-  local host = HOSTS[platform]
-  if not host or not creds then
-    return
-  end
-
-  local input = _build_input(host, { username = creds.username, password = creds.password })
-  vim.system({ 'git', 'credential', 'reject' }, { stdin = input, text = true }):wait()
-end
-
-return M

lua/cp/health.lua

@@ -5,12 +5,12 @@ local utils = require('cp.utils')
 local function check()
   vim.health.start('cp.nvim [required] ~')
 
-  local nvim_ver = vim.version()
+  utils.setup_python_env()
-  local nvim_str = ('%d.%d.%d'):format(nvim_ver.major, nvim_ver.minor, nvim_ver.patch)
+
   if vim.fn.has('nvim-0.10.0') == 1 then
-    vim.health.ok('Neovim >= 0.10.0: ' .. nvim_str)
+    vim.health.ok('Neovim 0.10.0+ detected')
   else
-    vim.health.error('Neovim >= 0.10.0 required, found ' .. nvim_str)
+    vim.health.error('cp.nvim requires Neovim 0.10.0+')
   end
 
   local uname = vim.uv.os_uname()
@@ -18,24 +18,6 @@ local function check()
     vim.health.error('Windows is not supported')
   end
 
-  local time_cap = utils.time_capability()
-  if time_cap.ok then
-    vim.health.ok('GNU time found: ' .. time_cap.path)
-  else
-    vim.health.error('GNU time not found: ' .. (time_cap.reason or ''))
-  end
-
-  local timeout_cap = utils.timeout_capability()
-  if timeout_cap.ok then
-    vim.health.ok('GNU timeout found: ' .. timeout_cap.path)
-  else
-    vim.health.error('GNU timeout not found: ' .. (timeout_cap.reason or ''))
-  end
-
-  vim.health.start('cp.nvim [optional] ~')
-
-  utils.setup_python_env()
-
   if utils.is_nix_build() then
     local source = utils.is_nix_discovered() and 'runtime discovery' or 'flake install'
     vim.health.ok('Nix Python environment detected (' .. source .. ')')
@@ -69,30 +51,18 @@ local function check()
     end
   end
 
-  if vim.fn.executable('git') == 1 then
+  local time_cap = utils.time_capability()
-    local r = vim.system({ 'git', '--version' }, { text = true }):wait()
+  if time_cap.ok then
-    if r.code == 0 then
+    vim.health.ok('GNU time found: ' .. time_cap.path)
-      local major, minor, patch = r.stdout:match('(%d+)%.(%d+)%.(%d+)')
-      major, minor, patch = tonumber(major), tonumber(minor), tonumber(patch or 0)
-      local ver_str = ('%d.%d.%d'):format(major or 0, minor or 0, patch or 0)
-      if
-        major
-        and (major > 1 or (major == 1 and minor > 7) or (major == 1 and minor == 7 and patch >= 9))
-      then
-        vim.health.ok('git >= 1.7.9: ' .. ver_str)
   else
-        vim.health.warn('git >= 1.7.9 required for credential storage, found ' .. ver_str)
+    vim.health.error('GNU time not found: ' .. (time_cap.reason or ''))
-      end
   end
 
-    local helper = vim.system({ 'git', 'config', 'credential.helper' }, { text = true }):wait()
+  local timeout_cap = utils.timeout_capability()
-    if helper.code == 0 and helper.stdout and vim.trim(helper.stdout) ~= '' then
+  if timeout_cap.ok then
-      vim.health.ok('git credential helper: ' .. vim.trim(helper.stdout))
+    vim.health.ok('GNU timeout found: ' .. timeout_cap.path)
   else
-      vim.health.warn('no git credential helper configured (required for login/submit)')
+    vim.health.error('GNU timeout not found: ' .. (timeout_cap.reason or ''))
-    end
-  else
-    vim.health.warn('git not found (required for credential storage)')
   end
 end
 

lua/cp/scraper.lua

@@ -347,9 +347,7 @@ function M.login(platform, credentials, on_status, callback)
     stdin = vim.json.encode(credentials),
     on_event = function(ev)
       if ev.credentials ~= nil and next(ev.credentials) ~= nil then
-        vim.schedule(function()
+        require('cp.cache').set_credentials(platform, ev.credentials)
-          require('cp.git_credential').store(platform, ev.credentials)
-        end)
       end
       if ev.status ~= nil then
         if type(on_status) == 'function' then
@@ -397,9 +395,7 @@ function M.submit(
     stdin = vim.json.encode(credentials),
     on_event = function(ev)
       if ev.credentials ~= nil and next(ev.credentials) ~= nil then
-        vim.schedule(function()
+        require('cp.cache').set_credentials(platform, ev.credentials)
-          require('cp.git_credential').store(platform, ev.credentials)
-        end)
       end
       if ev.status ~= nil then
         if type(on_status) == 'function' then

lua/cp/submit.lua

@@ -1,8 +1,8 @@
 local M = {}
 
+local cache = require('cp.cache')
 local config = require('cp.config')
 local constants = require('cp.constants')
-local git_credential = require('cp.git_credential')
 local logger = require('cp.log')
 local state = require('cp.state')
 
@@ -14,7 +14,7 @@ local STATUS_MSGS = {
 }
 
 local function prompt_credentials(platform, callback)
-  local saved = git_credential.get(platform)
+  local saved = cache.get_credentials(platform)
   if saved and saved.username and saved.password then
     callback(saved)
     return
@@ -42,14 +42,6 @@ end
 
 ---@param opts { language?: string }?
 function M.submit(opts)
-  if not git_credential.has_helper() then
-    logger.log(
-      'No git credential helper configured. See :help cp-credentials',
-      { level = vim.log.levels.ERROR }
-    )
-    return
-  end
-
   local platform = state.get_platform()
   local contest_id = state.get_contest_id()
   local problem_id = state.get_problem_id()
@@ -117,12 +109,12 @@ function M.submit(opts)
       function(result)
         vim.schedule(function()
           if result and result.success then
-            git_credential.store(platform, creds)
+            cache.set_credentials(platform, creds)
             logger.log('Submitted successfully', { level = vim.log.levels.INFO, override = true })
           else
             local err = result and result.error or 'unknown error'
             if err == 'bad_credentials' or err:match('^Login failed') then
-              git_credential.reject(platform, creds)
+              cache.clear_credentials(platform)
               logger.log(
                 'Submit failed: ' .. (constants.LOGIN_ERRORS[err] or err),
                 { level = vim.log.levels.ERROR }

lua/cp/utils.lua

@@ -366,10 +366,6 @@ function M.check_required_runtime()
     return false, timeout.reason
   end
 
-  if vim.fn.executable('git') ~= 1 then
-    return false, 'git is required for credential storage'
-  end
-
   return true
 end
 

plugin/cp.lua

@@ -8,7 +8,6 @@ vim.api.nvim_create_user_command('CP', function(opts)
   cp.handle_command(opts)
 end, {
   nargs = '*',
-  bar = true,
   desc = 'Competitive programming helper',
   complete = function(ArgLead, CmdLine, _)
     local constants = require('cp.constants')

scrapers/base.py

@@ -3,7 +3,6 @@ import json
 import os
 import re
 import sys
-import tempfile
 from abc import ABC, abstractmethod
 from pathlib import Path
 from typing import Any
@@ -21,18 +20,6 @@ from .models import (
 _COOKIE_FILE = Path.home() / ".cache" / "cp-nvim" / "cookies.json"
 
 
-def _atomic_write(path: Path, content: str) -> None:
-    fd, tmp = tempfile.mkstemp(dir=path.parent, prefix=".tmp-")
-    try:
-        os.fchmod(fd, 0o600)
-        with os.fdopen(fd, "w") as f:
-            f.write(content)
-        os.replace(tmp, path)
-    except BaseException:
-        os.unlink(tmp)
-        raise
-
-
 def load_platform_cookies(platform: str) -> Any | None:
     try:
         data = json.loads(_COOKIE_FILE.read_text())
@@ -42,20 +29,22 @@ def load_platform_cookies(platform: str) -> Any | None:
 
 
 def save_platform_cookies(platform: str, data: Any) -> None:
-    _COOKIE_FILE.parent.mkdir(parents=True, exist_ok=True, mode=0o700)
+    _COOKIE_FILE.parent.mkdir(parents=True, exist_ok=True)
     try:
         existing = json.loads(_COOKIE_FILE.read_text())
     except Exception:
         existing = {}
     existing[platform] = data
-    _atomic_write(_COOKIE_FILE, json.dumps(existing))
+    _COOKIE_FILE.write_text(json.dumps(existing))
+    _COOKIE_FILE.chmod(0o600)
 
 
 def clear_platform_cookies(platform: str) -> None:
     try:
         existing = json.loads(_COOKIE_FILE.read_text())
         existing.pop(platform, None)
-        _atomic_write(_COOKIE_FILE, json.dumps(existing))
+        _COOKIE_FILE.write_text(json.dumps(existing))
+        _COOKIE_FILE.chmod(0o600)
     except Exception:
         pass
 

scrapers/cses.py

@@ -8,12 +8,7 @@ from typing import Any
 
 import httpx
 
-from .base import (
+from .base import BaseScraper, extract_precision
-    BaseScraper,
-    extract_precision,
-    load_platform_cookies,
-    save_platform_cookies,
-)
 from .timeouts import HTTP_TIMEOUT
 from .models import (
     ContestListResult,
@@ -253,20 +248,35 @@ class CSESScraper(BaseScraper):
         if not username or not password:
             return self._login_error("Missing username or password")
 
-        token = load_platform_cookies("cses")
+        token = credentials.get("token")
         async with httpx.AsyncClient(follow_redirects=True) as client:
             if token:
                 print(json.dumps({"status": "checking_login"}), flush=True)
                 if await self._check_token(client, token):
-                    return LoginResult(success=True, error="")
+                    return LoginResult(
+                        success=True,
+                        error="",
+                        credentials={
+                            "username": username,
+                            "password": password,
+                            "token": token,
+                        },
+                    )
 
             print(json.dumps({"status": "logging_in"}), flush=True)
             token = await self._web_login(client, username, password)
             if not token:
                 return self._login_error("bad_credentials")
 
-            save_platform_cookies("cses", token)
+            return LoginResult(
-            return LoginResult(success=True, error="")
+                success=True,
+                error="",
+                credentials={
+                    "username": username,
+                    "password": password,
+                    "token": token,
+                },
+            )
 
     async def stream_tests_for_category_async(self, category_id: str) -> None:
         async with httpx.AsyncClient(
@@ -413,7 +423,7 @@ class CSESScraper(BaseScraper):
             return self._submit_error("Missing credentials. Use :CP login cses")
 
         async with httpx.AsyncClient(follow_redirects=True) as client:
-            token = load_platform_cookies("cses")
+            token = credentials.get("token")
 
             if token:
                 print(json.dumps({"status": "checking_login"}), flush=True)
@@ -425,7 +435,18 @@ class CSESScraper(BaseScraper):
                 token = await self._web_login(client, username, password)
                 if not token:
                     return self._submit_error("bad_credentials")
-                save_platform_cookies("cses", token)
+                print(
+                    json.dumps(
+                        {
+                            "credentials": {
+                                "username": username,
+                                "password": password,
+                                "token": token,
+                            }
+                        }
+                    ),
+                    flush=True,
+                )
 
             print(json.dumps({"status": "submitting"}), flush=True)