feat: first draft

tests/path_spec.lua

@@ -0,0 +1,32 @@
+local pathutil = require("oil.pathutil")
+describe("pathutil", function()
+  it("calculates parent path", function()
+    local cases = {
+      { "/foo/bar", "/foo/" },
+      { "/foo/bar/", "/foo/" },
+      { "/", "/" },
+      { "", "" },
+      { "foo/bar/", "foo/" },
+      { "foo", "" },
+    }
+    for _, case in ipairs(cases) do
+      local input, expected = unpack(case)
+      local output = pathutil.parent(input)
+      assert.equals(expected, output, string.format('Parent path "%s" failed', input))
+    end
+  end)
+
+  it("calculates basename", function()
+    local cases = {
+      { "/foo/bar", "bar" },
+      { "/foo/bar/", "bar" },
+      { "/", nil },
+      { "", nil },
+    }
+    for _, case in ipairs(cases) do
+      local input, expected = unpack(case)
+      local output = pathutil.basename(input)
+      assert.equals(expected, output, string.format('Basename "%s" failed', input))
+    end
+  end)
+end)