fix: right align file header description

README.md

@@ -54,7 +54,7 @@ Create a `Makefile` target:
 
 ```makefile
 .deps/docgen.nvim:
-	git clone --depth 1 --branch v1.0.0 https://github.com/jamestrew/docgen.nvim $@
+	git clone --depth 1 --branch v1.0.1 https://github.com/jamestrew/docgen.nvim $@
 
 .PHONY: docgen
 docgen: .deps/docgen.nvim

lua/docgen/renderer.lua

@@ -794,7 +794,7 @@ end
 ---@return string
 function M.render_file_header(name, description)
   local tag = string.format("*%s.txt*", name)
-  return string.format("%s\n\n", tag .. "   " .. description)
+  return string.format("%s%" .. (TEXT_WIDTH - #tag) .. "s\n\n", tag, description)
 end
 
 ---@param doc_lines string[]

tests/renderer_spec.lua

@@ -1087,3 +1087,18 @@ new paragraph
     assert_md(input, input)
   end)
 end)
+
+describe("file header", function()
+  it("works", function()
+    local result = renderer.render_file_header("myplugin", "My plugin description")
+    local lines = vim.split(result, "\n")
+    assert.equal(#lines, 3)
+
+    local line = lines[1]
+    assert.equal(type(line), "string")
+    ---@cast line string
+    assert.equal(78, #line)
+    assert.truthy(vim.startswith(line, "*myplugin.txt*"))
+    assert.truthy(vim.endswith(line, "My plugin description"))
+  end)
+end)