Reset all set attributes for every new cell

If a cell element was missing some attribute, we would retain the attributes of the previous cell.

lib/xlsx_reader/parsers/worksheet_parser.ex

@@ -314,14 +314,19 @@ defmodule XlsxReader.Parsers.WorksheetParser do
 
   ## Cell format handling
 
-  @cell_attributes_mapping %{
-    "r" => :cell_ref,
-    "s" => :cell_style,
-    "t" => :cell_type
-  }
-
   defp extract_cell_attributes(attributes) do
-    Utils.map_attributes(attributes, @cell_attributes_mapping)
+    # Initialize current cell attributes
+    Utils.map_attributes(
+      attributes,
+      %{
+        "r" => :cell_ref,
+        "s" => :cell_style,
+        "t" => :cell_type
+      },
+      # Make we start from a blank slate to prevent reusing the previous cell data
+      # if one of the attribute is missing
+      %{cell_ref: nil, cell_style: nil, cell_type: nil}
+    )
   end
 
   defp format_cell_data(state) do

test/compatibility_test.exs

@@ -112,4 +112,43 @@ defmodule CompatibilityTest do
     assert {:ok, [["", ""], ["", "b2"]]} = XlsxReader.sheet(package, "Sheet1", empty_rows: true)
     assert {:ok, [["", "b2"]]} = XlsxReader.sheet(package, "Sheet1", empty_rows: false)
   end
+
+  test "cells with missing attributes" do
+    # The worksheet has a mix of "s", "t" and no attributes
+    assert {:ok, package} = XlsxReader.open(TestFixtures.path("cells_missing_attributes.xlsx"))
+
+    assert {
+             :ok,
+             [
+               [
+                 "Number",
+                 "Name",
+                 "Effective Date",
+                 "ID Number",
+                 "Operator",
+                 "County",
+                 "State",
+                 "Product",
+                 "Description",
+                 "Acres"
+               ],
+               [
+                 "Number",
+                 "Name",
+                 # Date with s="5" is converted
+                 ~D[2024-07-01],
+                 # This cell has no attributes at all, it's treated as a string
+                 # and not converted to a date because all cell attributes are
+                 # properly reset
+                 "5575789630",
+                 "Operator",
+                 "County",
+                 "State",
+                 "Product",
+                 "Description",
+                 "Acres"
+               ]
+             ]
+           } = XlsxReader.sheet(package, "Sheet 1")
+  end
 end