feat: use selene to prevent accidental print statements

## Details

After leaving a print statement in the last push, wanted an automated
way to prevent this in the future. While there's no perfect solution I
did come up with one that works well enough.

Added a `selene.toml` with a `neovim` base. The base defines the `vim`
global (as any) along with the various test framework globals like
`describe`, `it`, and the various `assert` methods. Important for this
change specifically it also marks both `print` and `vim.print` as
deprecated. That way any usage of those functions fails the check.

Where we do want to allow these methods add `selene: allow(deprecated)`.

It's not accurate since the methods are not deprecated, but does allow
me to quickly catch any usage that has not been explicitly allowed.

Added a `check` step that runs both `selene` & `stylua` over all files.

Fixed / improved a few issues:

- caught an error where I defined `Providers` globally instead of locally
- inline luassert `assert` methods so that errors are found
- add allow for mixed table around minimal config
- always provide a message argument to regular `assert` method

Author: MeanderingProgrammer

benches/util.lua

@@ -1,8 +1,5 @@
 ---@module 'luassert'
 
-local Eq = assert.are.same
-local True = assert.True
-
 ---@class render.md.bench.Util
 local M = {}
 
@@ -53,14 +50,14 @@ end
 ---@param actual number
 ---@param max number
 function M.less_than(actual, max)
-    True(actual < max, ('expected %f < %f'):format(actual, max))
+    assert.is_true(actual < max, ('expected %f < %f'):format(actual, max))
 end
 
 ---@param expected integer
 function M.num_marks(expected)
     local ui = require('render-markdown.core.ui')
     local marks = vim.api.nvim_buf_get_extmarks(0, ui.ns, 0, -1, {})
-    Eq(expected, #marks)
+    assert.same(expected, #marks)
 end
 
 return M

demo/minit.lua

@@ -15,6 +15,7 @@ local lazypath = vim.fn.stdpath('data') .. '/lazy/lazy.nvim'
 assert(vim.uv.fs_stat(lazypath))
 vim.opt.rtp:prepend(lazypath)
 
+-- selene: allow(mixed_table)
 require('lazy').setup({
     dev = { path = '~/dev/repos/personal' },
     spec = {
@@ -32,7 +33,12 @@ require('lazy').setup({
             config = function()
                 ---@diagnostic disable-next-line: missing-fields
                 require('nvim-treesitter.configs').setup({
-                    ensure_installed = { 'markdown', 'markdown_inline', 'latex' },
+                    ensure_installed = {
+                        'html',
+                        'latex',
+                        'markdown',
+                        'markdown_inline',
+                    },
                     highlight = { enable = true },
                 })
             end,
@@ -56,7 +62,10 @@ require('lazy').setup({
         {
             'MeanderingProgrammer/render-markdown.nvim',
             dev = true,
-            dependencies = { 'nvim-treesitter/nvim-treesitter', 'echasnovski/mini.nvim' },
+            dependencies = {
+                'nvim-treesitter/nvim-treesitter',
+                'echasnovski/mini.nvim',
+            },
             config = function()
                 require('render-markdown').setup({})
             end,

doc/render-markdown.txt

@@ -1,4 +1,4 @@
-*render-markdown.txt*        For NVIM v0.11.1       Last change: 2025 April 28
+*render-markdown.txt*        For NVIM v0.11.1       Last change: 2025 April 29
 
 ==============================================================================
 Table of Contents                          *render-markdown-table-of-contents*

justfile

@@ -1,6 +1,6 @@
 init := "tests/minimal_init.lua"
 
-default: update test health
+default: update check test health
 
 update:
   # Updates types.lua & README.md
@@ -11,6 +11,10 @@ update:
     --project-name render-markdown \
     --input-file README.md
 
+check:
+  selene --quiet .
+  stylua --check .
+
 test:
   just busted "tests"
 

lua/render-markdown/api.lua

@@ -49,8 +49,10 @@ end
 function M.config()
     local difference = state.difference()
     if difference == nil then
+        -- selene: allow(deprecated)
         vim.print('default configuration')
     else
+        -- selene: allow(deprecated)
         vim.print(difference)
     end
 end

lua/render-markdown/core/log.lua

@@ -57,7 +57,8 @@ function M.runtime(name, callback)
             callback()
             local end_time = Compat.uv.hrtime()
             local elapsed = (end_time - start_time) / 1e+6
-            assert(elapsed < 1000)
+            assert(elapsed < 1000, 'invalid elapsed time')
+            -- selene: allow(deprecated)
             vim.print(('%8s : %5.1f ms'):format(name:upper(), elapsed))
         end
     else

lua/render-markdown/debug/marks.lua

@@ -25,7 +25,7 @@ end
 ---@return boolean
 function Mark.__lt(a, b)
     local as, bs = a:priorities(), b:priorities()
-    assert(#as == #bs)
+    assert(#as == #bs, 'priorities must be same length')
     for i = 1, #as do
         if as[i] ~= bs[i] then
             return as[i] < bs[i]
@@ -166,10 +166,13 @@ function M.show()
     table.sort(marks)
 
     if #marks == 0 then
+        -- selene: allow(deprecated)
         vim.print(('no marks on row: %d'):format(row))
     else
+        -- selene: allow(deprecated)
         vim.print(('marks on row: %d'):format(row))
         for _, mark in ipairs(marks) do
+            -- selene: allow(deprecated)
             vim.print(tostring(mark))
         end
     end

lua/render-markdown/handler/html.lua

@@ -37,7 +37,7 @@ function Handler:parse(root)
     local marks = Marks.new(self.context, true)
     self.context:query(root, self.query, function(capture, node)
         local renderer = self.renderers[capture]
-        assert(renderer ~= nil, 'Unhandled html capture: ' .. capture)
+        assert(renderer ~= nil, 'unhandled html capture: ' .. capture)
         local render = renderer:new(self.context, marks, node)
         if render:setup() then
             render:render()

lua/render-markdown/handler/markdown.lua

@@ -69,7 +69,7 @@ function Handler:parse(root)
     local marks = Marks.new(self.context, false)
     self.context:query(root, self.query, function(capture, node)
         local renderer = self.renderers[capture]
-        assert(renderer ~= nil, 'Unhandled markdown capture: ' .. capture)
+        assert(renderer ~= nil, 'unhandled markdown capture: ' .. capture)
         local render = renderer:new(self.context, marks, node)
         if render:setup() then
             render:render()

lua/render-markdown/handler/markdown_inline.lua

@@ -48,7 +48,7 @@ function Handler:parse(root)
     local marks = Marks.new(self.context, true)
     self.context:query(root, self.query, function(capture, node)
         local renderer = self.renderers[capture]
-        assert(renderer ~= nil, 'Unhandled inline capture: ' .. capture)
+        assert(renderer ~= nil, 'unhandled inline capture: ' .. capture)
         local render = renderer:new(self.context, marks, node)
         if render:setup() then
             render:render()

lua/render-markdown/health.lua

@@ -5,7 +5,7 @@ local state = require('render-markdown.state')
 local M = {}
 
 ---@private
-M.version = '8.3.18'
+M.version = '8.3.19'
 
 function M.check()
     M.start('version')

lua/render-markdown/integ/coq.lua

@@ -17,6 +17,7 @@ function M.setup()
     if not has_coq then
         return
     end
+    -- selene: allow(unscoped_variables)
     ---@type table<integer, table>
     COQsources = COQsources or {}
     COQsources[M.new_uid(COQsources)] = {

lua/render-markdown/integ/icons.lua

@@ -3,7 +3,7 @@
 ---@field get fun(filetype: string): string?, string?
 
 ---@class render.md.icon.Providers
-Providers = {}
+local Providers = {}
 
 ---@return render.md.icon.Provider?
 function Providers.MiniIcons()
@@ -15,6 +15,7 @@ function Providers.MiniIcons()
     if getter == nil then
         return nil
     end
+    -- selene: allow(global_usage)
     -- additional check recommended by author
     if _G.MiniIcons == nil then
         return nil

lua/render-markdown/lib/marks.lua

@@ -137,7 +137,7 @@ function Marks:update(mark)
     end
     local row, start_col = mark.start_row, mark.start_col
     if mark.opts.conceal ~= nil then
-        local end_col = assert(mark.opts.end_col)
+        local end_col = assert(mark.opts.end_col, 'conceal requires end_col')
         self.context.conceal:add(row, {
             start_col = start_col,
             end_col = end_col,

lua/render-markdown/render/base.lua

@@ -130,7 +130,7 @@ function Base:indent_line(virtual, level)
     if virtual then
         level = self:indent_level(level)
     else
-        assert(level ~= nil, 'Level must be known for real lines')
+        assert(level ~= nil, 'level must be known for real lines')
     end
     local line = {}
     if level > 0 then

neovim.yml

@@ -0,0 +1,40 @@
+---
+base: lua51
+
+globals:
+  vim:
+    any: true
+  vim.print:
+    args:
+      - type: ...
+    deprecated:
+      message: accidental print
+  print:
+    args:
+      - type: ...
+    deprecated:
+      message: accidental print
+  describe:
+    args:
+      - type: string
+      - type: function
+  it:
+    args:
+      - type: string
+      - type: function
+  assert.same:
+    args:
+      - type: any
+      - type: any
+      - type: string
+        required: false
+  assert.is_true:
+    args:
+      - type: bool
+      - type: string
+        required: false
+  assert.is_false:
+    args:
+      - type: bool
+      - type: string
+        required: false

selene.toml

@@ -0,0 +1,4 @@
+std = "neovim"
+
+[config]
+empty_if = { comments_count = true }

tests/comp_spec.lua

@@ -2,8 +2,6 @@
 
 local util = require('tests.util')
 
-local Eq = assert.are.same
-
 ---@param row integer
 ---@param col integer
 ---@param expected lsp.CompletionItem[]
@@ -13,7 +11,7 @@ local function assert_items(row, col, expected)
     table.sort(actual, function(a, b)
         return a.label < b.label
     end)
-    Eq(expected, actual)
+    assert.same(expected, actual)
 end
 
 ---@param prefix string

tests/helpers/details.lua

@@ -71,7 +71,7 @@ end
 ---@return boolean
 function MarkDetails.__lt(a, b)
     local as, bs = a:priorities(), b:priorities()
-    assert(#as == #bs)
+    assert(#as == #bs, 'priorities must be same length')
     for i = 1, #as do
         if as[i] ~= bs[i] then
             return as[i] < bs[i]

tests/latex_spec.lua

@@ -3,20 +3,17 @@
 local stub = require('luassert.stub')
 local util = require('tests.util')
 
-local Eq = assert.are.same
-local True = assert.True
-
 ---@param converter string
 ---@param responses table<string, string>
 local function set_responses(converter, responses)
     stub.new(vim.fn, 'executable', function(expr)
-        Eq(converter, expr)
+        assert.same(converter, expr)
         return 1
     end)
     stub.new(vim.fn, 'system', function(cmd, input)
-        Eq(converter, cmd)
+        assert.same(converter, cmd)
         local result = responses[input]
-        True(result ~= nil, 'No output for: ' .. input)
+        assert.is_true(result ~= nil, 'No output for: ' .. input)
         return result
     end)
 end

tests/minimal_init.lua

@@ -3,7 +3,7 @@
 local function get_path(name)
     local data_path = vim.fn.stdpath('data')
     local plugin_path = vim.fs.find(name, { path = data_path })
-    assert(#plugin_path == 1)
+    assert(#plugin_path == 1, 'plugin must have one path')
     return plugin_path[1]
 end
 

tests/range_spec.lua

@@ -2,39 +2,35 @@
 
 local Range = require('render-markdown.core.range')
 
-local Eq = assert.are.same
-local True = assert.True
-local False = assert.False
-
 describe('range', function()
     it('contains', function()
         local range = Range.new(5, 9)
-        True(range:contains(5, 9)) -- identity
-        True(range:contains(6, 8)) -- inside
-        False(range:contains(4, 10)) -- around
-        False(range:contains(3, 4)) -- before
-        False(range:contains(10, 11)) -- after
-        False(range:contains(4, 9)) -- start -1
-        False(range:contains(4, 8)) -- start & end -1
-        False(range:contains(5, 10)) -- end +1
-        False(range:contains(6, 10)) -- start & end +1
-        False(range:contains(4, 5)) -- ends @ start
-        False(range:contains(9, 10)) -- starts @ end
+        assert.is_true(range:contains(5, 9)) -- identity
+        assert.is_true(range:contains(6, 8)) -- inside
+        assert.is_false(range:contains(4, 10)) -- around
+        assert.is_false(range:contains(3, 4)) -- before
+        assert.is_false(range:contains(10, 11)) -- after
+        assert.is_false(range:contains(4, 9)) -- start -1
+        assert.is_false(range:contains(4, 8)) -- start & end -1
+        assert.is_false(range:contains(5, 10)) -- end +1
+        assert.is_false(range:contains(6, 10)) -- start & end +1
+        assert.is_false(range:contains(4, 5)) -- ends @ start
+        assert.is_false(range:contains(9, 10)) -- starts @ end
     end)
 
     it('overlaps', function()
         local range = Range.new(5, 9)
-        True(range:overlaps(5, 9)) -- identity
-        True(range:overlaps(6, 8)) -- inside
-        True(range:overlaps(4, 10)) -- around
-        False(range:overlaps(3, 4)) -- before
-        False(range:overlaps(10, 11)) -- after
-        True(range:overlaps(4, 9)) -- start -1
-        True(range:overlaps(4, 8)) -- start & end -1
-        True(range:overlaps(5, 10)) -- end +1
-        True(range:overlaps(6, 10)) -- start & end +1
-        True(range:overlaps(4, 5)) -- ends @ start
-        True(range:overlaps(9, 10)) -- starts @ end
+        assert.is_true(range:overlaps(5, 9)) -- identity
+        assert.is_true(range:overlaps(6, 8)) -- inside
+        assert.is_true(range:overlaps(4, 10)) -- around
+        assert.is_false(range:overlaps(3, 4)) -- before
+        assert.is_false(range:overlaps(10, 11)) -- after
+        assert.is_true(range:overlaps(4, 9)) -- start -1
+        assert.is_true(range:overlaps(4, 8)) -- start & end -1
+        assert.is_true(range:overlaps(5, 10)) -- end +1
+        assert.is_true(range:overlaps(6, 10)) -- start & end +1
+        assert.is_true(range:overlaps(4, 5)) -- ends @ start
+        assert.is_true(range:overlaps(9, 10)) -- starts @ end
     end)
 
     it('coalesce', function()
@@ -51,6 +47,6 @@ describe('range', function()
             Range.new(12, 20),
             Range.new(25, 30),
         }
-        Eq(expected, Range.coalesce(ranges))
+        assert.same(expected, Range.coalesce(ranges))
     end)
 end)