Add latex parser as optional and update health check

## Details

The requirements to get latex support working for this plugin are
not clear as shown by: #32.

Update the README to add the missing need for the latex parser.

More importantly the current health check logic only checked for
the minimum needs of this plugin as there was no way to indicate
whether the user wanted latex support or not.

Add a `latex_enabled` flag which defaults to true. Functionally it
does allow enabling / disabling the latex handler but it is mainly
used in the updated health check logic to check for the additional
requirements needed for latex, i.e. the parser and the latex2text
executable. Setting the flag to false allows users to remove these
warnings if they do not want latex support by this plugin.

Author: MeanderingProgrammer

Diff for: README.md

@@ -21,18 +21,21 @@ Plugin to improve viewing Markdown files in Neovim
 - Replaces checkboxes with provided characters based on whether they are checked
 - Replaces block quote leading `>` with provided character
 - Updates table borders with better border characters, does NOT automatically align
-- Basic support for `LaTeX` if `pylatexenc` is installed on system
+- Basic support for `LaTeX` if `latex` parser and `pylatexenc` are installed
 - Disable rendering when file is larger than provided value
 - Support for [callouts](https://github.com/orgs/community/discussions/16925)
 - Support custom handlers which are ran identically to native handlers
 
 # Dependencies
 
-- [markdown & markdown_inline](https://github.com/tree-sitter-grammars/tree-sitter-markdown)
-  parsers for [treesitter](https://github.com/nvim-treesitter/nvim-treesitter):
-  Used to parse `markdown` files
-- [pylatexenc](https://pypi.org/project/pylatexenc/) (Optional): Used to
-  transform `LaTeX` strings to appropriate unicode using `latex2text`
+- [treesitter](https://github.com/nvim-treesitter/nvim-treesitter) parsers:
+  - [markdown & markdown_inline](https://github.com/tree-sitter-grammars/tree-sitter-markdown):
+    Used to parse `markdown` files
+  - [latex](https://github.com/latex-lsp/tree-sitter-latex) (Optional):
+    Used to get `LaTeX` blocks from `markdown` files
+- System dependencies:
+  - [pylatexenc](https://pypi.org/project/pylatexenc/) (Optional):
+    Used to transform `LaTeX` strings to appropriate unicode using `latex2text`
 
 # Install
 
@@ -69,8 +72,10 @@ by the user.
 
 ```lua
 require('render-markdown').setup({
-    -- Configure whether Markdown should be rendered by default or not
+    -- Whether Markdown should be rendered by default or not
     start_enabled = true,
+    -- Whether LaTeX should be rendered, mainly used for health check
+    latex_enabled = true,
     -- Maximum file size (in MB) that this plugin will attempt to render
     -- Any file larger than this will effectively be ignored
     max_file_size = 1.5,

Diff for: doc/render-markdown.txt

@@ -1,4 +1,4 @@
-*render-markdown.txt*           For 0.10.0           Last change: 2024 June 03
+*render-markdown.txt*           For 0.10.0           Last change: 2024 June 05
 
 ==============================================================================
 Table of Contents                          *render-markdown-table-of-contents*
@@ -46,7 +46,7 @@ Plugin to improve viewing Markdown files in Neovim
 - Replaces checkboxes with provided characters based on whether they are checked
 - Replaces block quote leading `>` with provided character
 - Updates table borders with better border characters, does NOT automatically align
-- Basic support for `LaTeX` if `pylatexenc` is installed on system
+- Basic support for `LaTeX` if `latex` parser and `pylatexenc` are installed
 - Disable rendering when file is larger than provided value
 - Support for callouts <https://github.com/orgs/community/discussions/16925>
 - Support custom handlers which are ran identically to native handlers
@@ -55,11 +55,14 @@ Plugin to improve viewing Markdown files in Neovim
 ==============================================================================
 3. Dependencies                                 *render-markdown-dependencies*
 
-- markdown & markdown_inline <https://github.com/tree-sitter-grammars/tree-sitter-markdown>
-    parsers for treesitter <https://github.com/nvim-treesitter/nvim-treesitter>:
-    Used to parse `markdown` files
-- pylatexenc <https://pypi.org/project/pylatexenc/> (Optional): Used to
-    transform `LaTeX` strings to appropriate unicode using `latex2text`
+- treesitter <https://github.com/nvim-treesitter/nvim-treesitter> parsers:
+    - markdown & markdown_inline <https://github.com/tree-sitter-grammars/tree-sitter-markdown>:
+        Used to parse `markdown` files
+    - latex <https://github.com/latex-lsp/tree-sitter-latex> (Optional):
+        Used to get `LaTeX` blocks from `markdown` files
+- System dependencies:
+    - pylatexenc <https://pypi.org/project/pylatexenc/> (Optional):
+        Used to transform `LaTeX` strings to appropriate unicode using `latex2text`
 
 
 ==============================================================================
@@ -102,8 +105,10 @@ modified by the user.
 
 >lua
     require('render-markdown').setup({
-        -- Configure whether Markdown should be rendered by default or not
+        -- Whether Markdown should be rendered by default or not
         start_enabled = true,
+        -- Whether LaTeX should be rendered, mainly used for health check
+        latex_enabled = true,
         -- Maximum file size (in MB) that this plugin will attempt to render
         -- Any file larger than this will effectively be ignored
         max_file_size = 1.5,

Diff for: lua/render-markdown/handler/latex.lua

@@ -20,7 +20,6 @@ M.render = function(namespace, root, buf)
         logger.debug('Executable not found: ' .. converter)
         return
     end
-    logger.debug('Executable found: ' .. converter)
 
     local value = vim.treesitter.get_node_text(root, buf)
     local start_row, start_col, end_row, end_col = root:range()

Diff for: lua/render-markdown/health.lua

@@ -1,67 +1,96 @@
 local md = require('render-markdown')
 local state = require('render-markdown.state')
 
-local function validate_treesitter()
-    local ok, ts = pcall(require, 'nvim-treesitter.parsers')
-    if not ok then
-        vim.health.error('treesitter is not installed')
-        return
-    end
-    vim.health.ok('treesitter is installed')
+local M = {}
+
+function M.check()
+    local latex_advice = 'If you do not want LaTeX support avoid this warning by setting { latex_enabled = false }'
 
-    for _, name in ipairs({ 'markdown', 'markdown_inline' }) do
-        if ts.has_parser(name) then
-            vim.health.ok(name .. ' parser installed')
+    vim.health.start('markdown.nvim [nvim-treesitter]')
+    local ok = pcall(require, 'nvim-treesitter')
+    if ok then
+        vim.health.ok('installed')
+
+        M.check_parser('markdown')
+        M.check_parser('markdown_inline')
+        if state.config.latex_enabled then
+            M.check_parser('latex', latex_advice)
+        end
+
+        local highlight = require('nvim-treesitter.configs').get_module('highlight')
+        if highlight ~= nil and highlight.enable then
+            vim.health.ok('highlights enabled')
         else
-            vim.health.error(name .. ' parser not installed')
+            vim.health.error('highlights not enabled')
         end
+    else
+        vim.health.error('not installed')
+    end
+
+    vim.health.start('markdown.nvim [executables]')
+    if state.config.latex_enabled then
+        M.check_executable(state.config.latex_converter, latex_advice)
+    else
+        vim.health.ok('none to check')
+    end
+
+    vim.health.start('markdown.nvim [configuration]')
+    local errors = M.check_keys(md.default_config, state.config, {})
+    if #errors == 0 then
+        vim.health.ok('valid')
+    end
+    for _, message in ipairs(errors) do
+        vim.health.error(message)
+    end
+end
+
+---@param name string
+---@param advice string?
+function M.check_parser(name, advice)
+    local parsers = require('nvim-treesitter.parsers')
+    if parsers.has_parser(name) then
+        vim.health.ok(name .. ': parser installed')
+    elseif advice == nil then
+        vim.health.error(name .. ': parser not installed')
+    else
+        vim.health.warn(name .. ': parser not installed', advice)
     end
+end
 
-    local highlight = require('nvim-treesitter.configs').get_module('highlight')
-    if highlight ~= nil and highlight.enable then
-        vim.health.ok('treesitter highlights enabled')
+---@param name string
+---@param advice string?
+function M.check_executable(name, advice)
+    if vim.fn.executable(name) == 1 then
+        vim.health.ok(name .. ': installed')
+    elseif advice == nil then
+        vim.health.error(name .. ': not installed')
     else
-        vim.health.error('treesitter highlights not enabled')
+        vim.health.warn(name .. ': not installed', advice)
     end
 end
 
 ---@param t1 table<any, any>
 ---@param t2 table<any, any>
 ---@param path string[]
 ---@return string[]
-local function check_keys(t1, t2, path)
+function M.check_keys(t1, t2, path)
     local errors = {}
     for k, v2 in pairs(t2) do
         local v1 = t1[k]
         local key_path = vim.list_extend(vim.list_extend({}, path), { k })
-        local key = vim.fn.join(key_path, ' -> ')
+        local key = vim.fn.join(key_path, '.')
         if v1 == nil then
-            table.insert(errors, string.format('Invalid parameter: %s', key))
+            table.insert(errors, string.format('Invalid key: %s', key))
         elseif type(v1) ~= type(v2) then
-            table.insert(errors, string.format('Invalid type: %s, expected %s but found %s', key, type(v1), type(v2)))
+            table.insert(errors, string.format('Invalid type: %s, expected %s, found %s', key, type(v1), type(v2)))
         elseif type(v1) == 'table' and type(v2) == 'table' then
             -- Some tables are meant to have unrestricted keys
             if not vim.list_contains({ 'win_options', 'custom_handlers' }, k) then
-                vim.list_extend(errors, check_keys(v1, v2, key_path))
+                vim.list_extend(errors, M.check_keys(v1, v2, key_path))
             end
         end
     end
     return errors
 end
 
-local M = {}
-
-function M.check()
-    vim.health.start('Validating treesitter parsers & settings')
-    validate_treesitter()
-    vim.health.start('Validating configuration')
-    local errors = check_keys(md.default_config, state.config, {})
-    if #errors == 0 then
-        vim.health.ok('Configuration is valid')
-    end
-    for _, message in ipairs(errors) do
-        vim.health.error(message)
-    end
-end
-
 return M

Diff for: lua/render-markdown/init.lua

@@ -47,6 +47,7 @@ local M = {}
 
 ---@class render.md.UserConfig
 ---@field public start_enabled? boolean
+---@field public latex_enabled? boolean
 ---@field public max_file_size? number
 ---@field public markdown_query? string
 ---@field public inline_query? string
@@ -67,8 +68,10 @@ local M = {}
 
 ---@type render.md.Config
 M.default_config = {
-    -- Configure whether Markdown should be rendered by default or not
+    -- Whether Markdown should be rendered by default or not
     start_enabled = true,
+    -- Whether LaTeX should be rendered, mainly used for health check
+    latex_enabled = true,
     -- Maximum file size (in MB) that this plugin will attempt to render
     -- Any file larger than this will effectively be ignored
     max_file_size = 1.5,

Diff for: lua/render-markdown/types.lua

@@ -34,6 +34,7 @@
 
 ---@class render.md.Config
 ---@field public start_enabled boolean
+---@field public latex_enabled boolean
 ---@field public max_file_size number
 ---@field public markdown_query string
 ---@field public inline_query string

Diff for: lua/render-markdown/ui.lua

@@ -40,7 +40,7 @@ M.refresh = function(buf)
                 markdown.render(M.namespace, tree:root(), buf)
             elseif language == 'markdown_inline' then
                 markdown_inline.render(M.namespace, tree:root(), buf)
-            elseif language == 'latex' then
+            elseif language == 'latex' and state.config.latex_enabled then
                 latex.render(M.namespace, tree:root(), buf)
             else
                 logger.debug('No handler found')