test(config): verify Vim/Neovim config payload parity

Expose the init_options payload builders publicly in both clients
(M.init_options/M.server_settings in Lua, nuwiki#lsp#settings() in Vim) so
they can be inspected. Add editor harnesses that dump each client's
server-bound config as deterministic key=value lines and diff against a
shared golden file: nvim == golden and vim == golden together prove the two
clients send identical config. Add a server-side test asserting the Vim flat
shape and the Neovim {nuwiki:{...}} wrapper desugar to the same WikiConfig.
Wire both harnesses into CI.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

development/tests/config-expected.txt

@@ -0,0 +1,17 @@
+[default]
+wiki_root=~/vimwiki
+file_extension=.wiki
+syntax=vimwiki
+log_level=warn
+[sample]
+wiki_root=/tmp/base
+file_extension=.md
+syntax=vimwiki
+log_level=debug
+wikis[0].diary_rel_path=journal
+wikis[0].file_extension=.wiki
+wikis[0].index=home
+wikis[0].name=personal
+wikis[0].root=/tmp/personal
+wikis[1].name=work
+wikis[1].root=/tmp/work

development/tests/test-config-vim.sh

@@ -0,0 +1,58 @@
+#!/usr/bin/env bash
+#
+# development/tests/test-config-vim.sh — Vim counterpart of test-config.sh.
+#
+# Runs development/tests/test-config-vim.vim under headless Vim, which dumps
+# the Vim client's `initialization_options` payload (nuwiki#lsp#settings())
+# as `key=value` lines, then diffs against the shared golden
+# config-expected.txt. Matching the same golden the Neovim harness uses is
+# what proves Vim/Neovim config parity.
+#
+# Exit code: 0 when the payload matches the golden, 1 otherwise. Skips
+# (exit 0) when vim is not installed.
+
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+
+log() { printf '\033[1;34m[config-vim]\033[0m %s\n' "$*"; }
+
+if ! command -v vim >/dev/null 2>&1; then
+  log 'vim not installed — skipping'
+  exit 0
+fi
+
+TMP="$(mktemp -d -t nuwiki-config-vim-test-XXXXXX)"
+trap 'rm -rf "$TMP"' EXIT
+
+GOLDEN="$REPO_ROOT/development/tests/config-expected.txt"
+OUT="$TMP/vim-config.txt"
+
+VIMRC="$TMP/vimrc"
+cat > "$VIMRC" <<EOF
+set nocompatible
+let &runtimepath = '$REPO_ROOT' . ',' . &runtimepath
+filetype plugin indent on
+EOF
+
+log 'running Vim config harness…'
+# `</dev/null` so ex-mode doesn't hang on stdin; `timeout` guards CI.
+NUWIKI_CONFIG_OUT="$OUT" \
+  timeout 30 vim -e -s -u "$VIMRC" \
+    -c "source $REPO_ROOT/development/tests/test-config-vim.vim" \
+    </dev/null >"$TMP/vim.log" 2>&1 || true
+
+if [[ ! -f "$OUT" ]]; then
+  echo 'config harness produced no output' >&2
+  echo '--- vim log ---' >&2
+  cat "$TMP/vim.log" >&2 || true
+  exit 1
+fi
+
+if diff -u "$GOLDEN" "$OUT"; then
+  log 'Vim config payload matches golden ✓'
+  exit 0
+fi
+
+echo 'Vim config payload DIVERGED from golden (see diff above)' >&2
+exit 1

development/tests/test-config-vim.vim

@@ -0,0 +1,50 @@
+" development/tests/test-config-vim.vim — Vim counterpart of
+" test-config.lua. Dumps the Vim client's `initialization_options` payload
+" (nuwiki#lsp#settings()) for the same two scenarios as the Neovim harness,
+" as byte-identical `key=value` lines, so both can be diffed against the
+" shared golden development/tests/config-expected.txt.
+"
+" "nvim == golden" and "vim == golden" together prove Vim/Neovim config
+" parity for everything the server consumes.
+
+let s:out = $NUWIKI_CONFIG_OUT
+let s:lines = []
+
+function! s:dump(payload) abort
+  call add(s:lines, 'wiki_root=' . a:payload.wiki_root)
+  call add(s:lines, 'file_extension=' . a:payload.file_extension)
+  call add(s:lines, 'syntax=' . a:payload.syntax)
+  call add(s:lines, 'log_level=' . a:payload.log_level)
+  if has_key(a:payload, 'wikis')
+    let l:i = 0
+    for l:w in a:payload.wikis
+      for l:k in sort(keys(l:w))
+        call add(s:lines, printf('wikis[%d].%s=%s', l:i, l:k, l:w[l:k]))
+      endfor
+      let l:i += 1
+    endfor
+  endif
+endfunction
+
+" Scenario 1: defaults (no globals set).
+unlet! g:nuwiki_wiki_root g:nuwiki_file_extension g:nuwiki_syntax
+unlet! g:nuwiki_log_level g:nuwiki_wikis
+call add(s:lines, '[default]')
+call s:dump(nuwiki#lsp#settings())
+
+" Scenario 2: same representative config as the Neovim harness.
+let g:nuwiki_wiki_root      = '/tmp/base'
+let g:nuwiki_file_extension = '.md'
+let g:nuwiki_syntax         = 'vimwiki'
+let g:nuwiki_log_level      = 'debug'
+let g:nuwiki_wikis = [
+      \ { 'name': 'personal', 'root': '/tmp/personal',
+      \   'file_extension': '.wiki', 'index': 'home',
+      \   'diary_rel_path': 'journal' },
+      \ { 'name': 'work', 'root': '/tmp/work' },
+      \ ]
+call add(s:lines, '[sample]')
+call s:dump(nuwiki#lsp#settings())
+
+call writefile(s:lines, s:out)
+qall!

development/tests/test-config.lua

@@ -0,0 +1,74 @@
+-- development/tests/test-config.lua — dump the Neovim client's
+-- `initialization_options` payload for two scenarios (default config and a
+-- representative multi-wiki sample) as deterministic `key=value` lines.
+--
+-- The runner (test-config.sh) diffs the output against
+-- development/tests/config-expected.txt. The Vim harness
+-- (test-config-vim.vim) emits byte-identical lines against the SAME golden,
+-- so "nvim == golden" and "vim == golden" together prove the two clients
+-- send the same server-bound config — i.e. Vim/Neovim config parity.
+--
+-- Only the server-relevant keys are emitted (wiki_root, file_extension,
+-- syntax, log_level, wikis[*]). `mappings`/`folding` are client-side
+-- concerns the server ignores, so they're intentionally excluded.
+
+local out = assert(os.getenv('NUWIKI_CONFIG_OUT'), 'NUWIKI_CONFIG_OUT unset')
+
+local config = require('nuwiki.config')
+local lsp = require('nuwiki.lsp')
+
+local lines = {}
+local function emit(s)
+  lines[#lines + 1] = s
+end
+
+local function dump(payload)
+  emit('wiki_root=' .. tostring(payload.wiki_root))
+  emit('file_extension=' .. tostring(payload.file_extension))
+  emit('syntax=' .. tostring(payload.syntax))
+  emit('log_level=' .. tostring(payload.log_level))
+  if payload.wikis then
+    for i, w in ipairs(payload.wikis) do
+      local keys = {}
+      for k in pairs(w) do
+        keys[#keys + 1] = k
+      end
+      table.sort(keys)
+      for _, k in ipairs(keys) do
+        emit(string.format('wikis[%d].%s=%s', i - 1, k, tostring(w[k])))
+      end
+    end
+  end
+end
+
+-- Scenario 1: defaults (no user config, no VimL globals).
+vim.g.nuwiki_wikis = nil
+config.apply({})
+emit('[default]')
+dump(lsp.init_options())
+
+-- Scenario 2: representative config exercising scalar keys + a wikis list.
+config.apply({
+  wiki_root = '/tmp/base',
+  file_extension = '.md',
+  syntax = 'vimwiki',
+  log_level = 'debug',
+  wikis = {
+    {
+      name = 'personal',
+      root = '/tmp/personal',
+      file_extension = '.wiki',
+      index = 'home',
+      diary_rel_path = 'journal',
+    },
+    { name = 'work', root = '/tmp/work' },
+  },
+})
+emit('[sample]')
+dump(lsp.init_options())
+
+local f = assert(io.open(out, 'w'))
+f:write(table.concat(lines, '\n') .. '\n')
+f:close()
+
+vim.cmd('qa!')

development/tests/test-config.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+#
+# development/tests/test-config.sh — verify the Neovim client builds the
+# exact `initialization_options` payload the server expects.
+#
+# Runs development/tests/test-config.lua under headless Neovim, which dumps
+# the server-bound config (wiki_root, file_extension, syntax, log_level,
+# wikis[*]) for a default and a sample scenario as `key=value` lines, then
+# diffs the result against the shared golden config-expected.txt.
+#
+# The Vim harness (test-config-vim.sh) diffs against the SAME golden, so a
+# green run of both proves Vim/Neovim config parity.
+#
+# Exit code: 0 when the payload matches the golden, 1 otherwise.
+
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+TMP="$(mktemp -d -t nuwiki-config-test-XXXXXX)"
+trap 'rm -rf "$TMP"' EXIT
+
+log() { printf '\033[1;34m[config-test]\033[0m %s\n' "$*"; }
+
+GOLDEN="$REPO_ROOT/development/tests/config-expected.txt"
+OUT="$TMP/nvim-config.txt"
+
+# No LSP server needed — we only inspect the payload the client would send.
+INIT="$TMP/init.lua"
+cat > "$INIT" <<EOF
+vim.opt.runtimepath:prepend('$REPO_ROOT')
+EOF
+
+log 'running Neovim config harness…'
+NUWIKI_CONFIG_OUT="$OUT" \
+  timeout 30 nvim --clean -u "$INIT" --headless \
+    -c "luafile $REPO_ROOT/development/tests/test-config.lua" \
+    >"$TMP/nvim.log" 2>&1 || true
+
+if [[ ! -f "$OUT" ]]; then
+  echo 'config harness produced no output' >&2
+  echo '--- nvim log ---' >&2
+  cat "$TMP/nvim.log" >&2 || true
+  exit 1
+fi
+
+if diff -u "$GOLDEN" "$OUT"; then
+  log 'Neovim config payload matches golden ✓'
+  exit 0
+fi
+
+echo 'Neovim config payload DIVERGED from golden (see diff above)' >&2
+exit 1