Refactor of default generator

lua/neogen/generators/default.lua

@@ -1,19 +1,59 @@
 local ts_utils = require("nvim-treesitter.ts_utils")
 
+--- Generates the prefix according to `template` options.
+--- Prefix is generated with an offset (currently spaces) repetition of `n` times.
+--- If `template.use_default_comment` is not set to false, the `commentstring` is added
+--- @param template table
+--- @param commentstring string
+--- @param n integer
+--- @return string
+local function prefix_generator(template, commentstring, n)
+    local prefix = (" "):rep(n)
+
+    -- Do not append the comment string if not wanted
+    if template.use_default_comment ~= false then
+        prefix = prefix .. commentstring
+    end
+    return prefix
+end
+
+--- Does some checks within the `value` and adds the `prefix` before it if required
+--- @param prefix string
+--- @param value string
+--- @return string
+local function conditional_prefix_inserter(prefix, value)
+    if value == "" then
+        return value
+    else
+        return prefix .. value
+    end
+end
+
+--- Insert values from `items` in `result` and returns it
+--- @param result table
+--- @param items table
+--- @param prefix string
+--- @return table result
+local function add_values_to_result(result, items, prefix)
+    for _, value in ipairs(items) do
+        local inserted = conditional_prefix_inserter(prefix, value)
+        table.insert(result, inserted)
+    end
+    return result
+end
+
 ---Default Generator:
 ---Uses the provided template to format the annotations with data found by the granulator
 --- @param parent userdata the node used to generate the annotations
 --- @param data table the data from the granulator, which is a set of [type] = results
 --- @param template table a template from the configuration
 --- @return table { line, content, opts }, with line being the line to append the content
-
 neogen.default_generator = function(parent, data, template)
     local start_row, start_column, end_row, end_column = ts_utils.get_node_range(parent)
     local commentstring, generated_template = vim.trim(vim.api.nvim_buf_get_option(0, "commentstring"):format(""))
 
     local row_to_place = start_row
     local col_to_place = start_column
-
     local append = template.append or {}
 
     if append.position == "after" then
@@ -40,53 +80,33 @@ neogen.default_generator = function(parent, data, template)
 
     local function parse_generated_template()
         local result = {}
-        local prefix = (" "):rep(col_to_place)
-
-        -- Do not append the comment string if not wanted
-        if template.use_default_comment ~= false then
-            prefix = prefix .. commentstring
-        end
+        local prefix = prefix_generator(template, commentstring, col_to_place)
 
         for _, values in ipairs(generated_template) do
             local type = values[1]
             local formatted_string = values[2]
             local opts = values[3] or {}
-            
+
             -- Will append the item before all their nodes
             if opts.before_first_item and data[type] then
-                for i, value in ipairs(opts.before_first_item) do
-                    if value == "" then
-                        table.insert(result, value)
-                    else
-                        table.insert(result, prefix .. value)
-                    end
-                end
+                result = add_values_to_result(result, opts.before_first_item, prefix)
             end
 
             -- If there is no data returned, will append the string with opts.no_results
             if opts.no_results == true and vim.tbl_isempty(data) then
-                if formatted_string == "" then
-                    table.insert(result, formatted_string)
-                else
-                    table.insert(result, prefix .. formatted_string)
-                end
+                local inserted = conditional_prefix_inserter(prefix, formatted_string)
+                table.insert(result, inserted)
             else
                 -- append the output as is
                 if type == nil and opts.no_results ~= true and not vim.tbl_isempty(data) then
-                    if formatted_string == "" then
-                        table.insert(result, formatted_string)
-                    else
-                        table.insert(result, prefix .. formatted_string:format(""))
-                    end
+                    local inserted = conditional_prefix_inserter(prefix, formatted_string:format(""))
+                    table.insert(result, inserted)
                 else
                     -- Format the output with the corresponding data
                     if data[type] then
                         for _, value in ipairs(data[type]) do
-                            if formatted_string == "" then
-                                table.insert(result, formatted_string)
-                            else
-                                table.insert(result, prefix .. formatted_string:format(value))
-                            end
+                            local inserted = conditional_prefix_inserter(prefix, formatted_string:format(value))
+                            table.insert(result, inserted)
                         end
                     end
                 end