feat: add progress_path helper with basic tests

spec/14-progress_spec.lua

@@ -2,7 +2,6 @@ local helpers = require "spec.helpers"
 
 
 describe("terminal.progress", function()
-
   local progress
   local t
   local utils
@@ -23,20 +22,15 @@ describe("terminal.progress", function()
     color = require "terminal.text.color"
   end)
 
-
   teardown(function()
     helpers.unload()
   end)
 
-
   before_each(function()
     helpers.clear_output()
   end)
 
-
-
   describe("spinner()", function()
-
     it("uses visible width for colored sprites (ignores ANSI)", function()
       local red_sprite = color.fore_seq("red") .. COLORED_SPRITE_CHAR
       local expected_width = width.utf8swidth(utils.strip_ansi(red_sprite))
@@ -50,7 +44,6 @@ describe("terminal.progress", function()
       assert.are.equal(red_sprite .. t.cursor.position.left_seq(expected_width), helpers.get_output())
     end)
 
-
     it("uses visible width for colored done_sprite", function()
       local done_sprite = color.fore_seq("green") .. DONE_MESSAGE_TEXT
       local done_width = width.utf8swidth(utils.strip_ansi(done_sprite))
@@ -65,7 +58,6 @@ describe("terminal.progress", function()
       assert.are.equal(done_sprite .. t.cursor.position.left_seq(done_width), helpers.get_output())
     end)
 
-
     it("works correctly for plain sprites without ANSI", function()
       local spinner = progress.spinner({
         sprites = { [0] = "", PLAIN_SPRITE_CHAR },
@@ -80,7 +72,39 @@ describe("terminal.progress", function()
         helpers.get_output()
       )
     end)
-
   end)
 
+  describe("progress_path()", function()
+    it("returns the correct number of frames", function()
+      local result = progress.progress_path(5)
+      assert.are.equal(5, #result)
+    end)
+
+    it("shows the runner moving toward the start position", function()
+      local result = progress.progress_path(4, "S", ">")
+      assert.are.equal("S...>", result[1])
+      assert.are.equal("S..>", result[2])
+      assert.are.equal("S.>", result[3])
+      assert.are.equal("S>", result[4])
+    end)
+
+    it("uses default icons when none are provided", function()
+      local result = progress.progress_path(3)
+      assert.are.equal("📍..🚙", result[1])
+      assert.are.equal("📍.🚙", result[2])
+      assert.are.equal("📍🚙", result[3])
+    end)
+
+    it("works with custom icons", function()
+      local result = progress.progress_path(3, "[", "O")
+      assert.are.equal("[..O", result[1])
+      assert.are.equal("[.O", result[2])
+      assert.are.equal("[O", result[3])
+    end)
+
+    it("handles zero width", function()
+      local result = progress.progress_path(0)
+      assert.are.equal(0, #result)
+    end)
+  end)
 end)

src/terminal/progress.lua

@@ -134,6 +134,35 @@ end
 
 
 
+--- Path progress animation where a runner moves toward the start position.
+-- Returns a table of animation frames for use as a sprite sequence with `spinner()`.
+--
+-- Example:
+--   local frames = M.progress_path(5, "📍", "🚙")
+--   -- frames[1] = "📍....🚙"
+--   -- frames[5] = "📍🚙"
+--
+-- @tparam[opt=20] number width number of animation frames (not visual width)
+-- @tparam[opt="📍"] string start_icon icon at the start (left) position
+-- @tparam[opt="🚙"] string runner_icon icon representing the runner
+-- @treturn table array of animation frame strings
+function M.progress_path(width, start_icon, runner_icon)
+  width = width or 20
+  start_icon = start_icon or "📍"
+  runner_icon = runner_icon or "🚙"
+
+  local result = {}
+
+  for i = 1, width do
+    local dots = string.rep(".", width - i)
+    result[i] = start_icon .. dots .. runner_icon
+  end
+
+  return result
+end
+
+
+
 --- Create a text/led ticker like sprite-sequence for use with a progress spinner.
 -- @tparam string text the text to display
 -- @tparam[opt=40] number width the width of the ticker, in characters