feat(ex.lsp.null_ls): add a new component to show actual null-ls sources

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README.md

@@ -17,6 +17,7 @@ for `lualine.nvim` with additional components.
     - [ex.git.branch](#exgitbranch)
     - [ex.lsp.single](#exlspsingle)
     - [ex.lsp.all](#exlspall)
+    - [ex.lsp.null_ls](#exlspnull_ls)
  - [🛠️ Tools](#tools)
 
 ## 📥 <a name="installation">Installation</a>
@@ -471,6 +472,46 @@ on_click = function(clicks, button, modified)
 end
 ```
 
+### ex.lsp.null_ls
+
+This component shows names of the
+[null-ls](https://github.com/nvimtools/none-ls.nvim) sources according to the specified
+[`query`](https://github.com/nvimtools/none-ls.nvim/blob/main/doc/SOURCES.md#get_sourcequery).
+By default, it shows names of all sources actual to the current buffer. All
+duplicated names are merged.
+
+```lua
+sections = {
+  lualine_a = {
+    {
+      'ex.lsp.null_ls',
+
+      -- The table or function that returns the table with the source query.
+      -- By default it shows only actual sorces. To show all registered sources
+      -- you can use just empty table:
+      -- query = {}
+      query = function()
+        return { filetype = vim.bo.filetype }
+      end,
+
+      -- The string separator between names
+      source_names_separator = ',',
+
+      -- The color for the disabled component:
+      disabled_color = { fg = 'grey' }
+
+      -- The color for the icon of the disabled component:
+      disabled_icon_color = { fg = 'grey' }
+    }
+  }
+}
+```
+
+No one source:&nbsp;<img height="18" alt="null-ls-disabled" src="https://github.com/dokwork/lualine-ex/assets/6939832/04ce4a14-a3f9-4d90-a229-d19b78fa7c11">
+The `jq` and the `spell` sources are active for the current buffer:<img height="18" alt="nulll-ls-enabled" src="https://github.com/dokwork/lualine-ex/assets/6939832/dda7dbb4-8647-49a2-8c28-8d29a617c2b9">
+
+
+
 ## 🛠️ <a name="tools">Tools</a>
 This plugin provide additional tools to help you create your own components. Read more details here:
 [Tools.md](Tools.md).

lua/lualine/components/ex/lsp/null_ls.lua

@@ -0,0 +1,76 @@
+local log = require('plenary.log').new({ plugin = 'ex.lsp.null-ls' })
+
+-- we should be ready to three possible cases:
+-- * when null-ls is not loaded we should load it only on demand;
+-- * when null-ls is not installed we should mock it to avoid errors;
+-- * when it is installed and loaded we should it use it.
+local null_ls = setmetatable({}, {
+    __index = function(self, key)
+        -- attempt to lazy load null-ls plugin
+        if rawget(self, 'is_installed') == nil then
+            local is_installed, null_ls = pcall(require, 'null-ls')
+            rawset(self, 'is_installed', is_installed)
+            rawset(self, 'null_ls', null_ls)
+            if is_installed then
+                log.debug('null-ls is installed')
+            else
+                log.warn('null-ls is not installed.')
+            end
+        end
+        -- return original plugin if it's installed
+        if rawget(self, 'is_installed') then
+            return rawget(self, 'null_ls')[key]
+        end
+        -- return mock:
+        if key == 'get_source' then
+            return {}
+        elseif key == 'is_registered' then
+            return false
+        else
+            return nil
+        end
+    end,
+})
+
+local NullLS = require('lualine.ex.component'):extend({
+    icon = '',
+    query = function()
+        return { filetype = vim.bo.filetype }
+    end,
+    component_name = 'ex_lsp_null_ls',
+    source_names_separator = ',',
+    is_enabled = function(component)
+        return null_ls.is_registered(component:get_query())
+    end,
+})
+
+function NullLS:get_query()
+    if type(self.options.query) == 'function' then
+        return self.options.query()
+    else
+        return self.options.query
+    end
+end
+
+-- get sources by query, and concatenate their unique names with {source_names_separator}
+function NullLS:update_status()
+    local sources = null_ls.get_source(self:get_query())
+    log.fmt_debug(
+        'For query %s was found sources: %s',
+        vim.inspect(self.options.query),
+        vim.inspect(sources)
+    )
+    local names_set = {}
+    local names = {}
+    for _, source in pairs(sources) do
+        -- merge similar sources and escape special symbols
+        if not names_set[source.name] then
+            names_set[source.name] = true
+            local escaped_name = string.gsub(source.name, '%%', '%%%%')
+            table.insert(names, escaped_name)
+        end
+    end
+    return table.concat(names, self.options.source_names_separator)
+end
+
+return NullLS

tests/components/null_ls_spec.lua

@@ -0,0 +1,47 @@
+local null_ls = require('null-ls')
+local l = require('tests.ex.lualine')
+local t = require('tests.ex.busted') --:ignore_all_tests()
+
+local eq = assert.are.equal
+
+local component_name = 'ex.lsp.null_ls'
+describe(component_name, function()
+    null_ls.setup({
+        sources = {
+            null_ls.builtins.completion.spell,
+            null_ls.builtins.formatting.stylua,
+            null_ls.builtins.hover.dictionary,
+            null_ls.builtins.diagnostics.clang_check,
+        },
+    })
+    describe('draw method', function()
+        it('should show the name of any source only once', function()
+            l.test_matched_component(component_name, function(ctbl)
+                local expected = {
+                    clang_check = true,
+                    spell = true,
+                    dictionary = true,
+                    stylua = true,
+                }
+                for name in string.gmatch(ctbl.value, '%w+') do
+                    assert(expected[name], 'Unexpected name ' .. name)
+                    expected[name] = nil
+                end
+            end)
+        end)
+        it('by default should return only sources for the current filetypes or for all', function()
+            vim.bo.filetype = 'lua'
+            l.test_matched_component(component_name, opts, function(ctbl)
+                for name in string.gmatch(ctbl.value, '%w+') do
+                    assert(name ~= 'clang_check', 'Unexpected name ' .. name)
+                end
+            end)
+        end)
+        it('should show names only of sources sutisfied to the query', function()
+            local opts = { query = { method = null_ls.methods.HOVER } }
+            l.test_matched_component(component_name, opts, function(ctbl)
+                eq('dictionary', ctbl.value)
+            end)
+        end)
+    end)
+end)