chore: plenary tests POC

tests/unit/utils_spec.lua

@@ -1,5 +1,6 @@
 ---@type Luassert
 local assert = require("luassert")
+local stub = require("luassert.stub")
 
 local utils = require("nvim-tree.utils")
 
@@ -8,10 +9,29 @@ describe("utils.path_add_trailing", function()
   end)
 
   it("trailing added", function()
-    assert.equals(utils.path_add_trailing("foo"), "foo/")
+    assert.equals("foo/", utils.path_add_trailing("foo"))
   end)
 
   it("trailing already present", function()
-    assert.equals(utils.path_add_trailing("foo/"), "foo/")
+    assert.equals("foo/", utils.path_add_trailing("foo/"))
+  end)
+end)
+
+describe("utils.canonical_path", function()
+
+  before_each(function()
+    stub(vim.fn, "has")
+  end)
+
+  after_each(function()
+  end)
+
+  it("is windows", function()
+    vim.fn.has.on_call_with("win32unix").returns(1)
+    assert.equals("C:\\foo\\bar", utils.canonical_path("c:\\foo\\bar"), "should be uppercase drive")
+  end)
+
+  it("not windows", function()
+    assert.equals("c:\\foo\\bar", utils.canonical_path("c:\\foo\\bar"))
   end)
 end)