BUG: don't manipulate styler object due to args in to_html

doc/source/whatsnew/v1.4.0.rst

@@ -355,7 +355,7 @@ ExtensionArray
 Styler
 ^^^^^^
 - Minor bug in :class:`.Styler` where the ``uuid`` at initialization maintained a floating underscore (:issue:`43037`)
--
+- Bug in :meth:`.Styler.to_html` where the ``Styler`` object was updated if the ``to_html`` method was called with some args (:issue:`43034`)
 
 Other
 ^^^^^

pandas/io/formats/style.py

@@ -900,19 +900,21 @@ def to_html(
         --------
         DataFrame.to_html: Write a DataFrame to a file, buffer or string in HTML format.
         """
+        obj = self._copy(deepcopy=True)  # manipulate table_styles on obj, not self
+
         if table_uuid:
-            self.set_uuid(table_uuid)
+            obj.set_uuid(table_uuid)
 
         if table_attributes:
-            self.set_table_attributes(table_attributes)
+            obj.set_table_attributes(table_attributes)
 
         if sparse_index is None:
             sparse_index = get_option("styler.sparse.index")
         if sparse_columns is None:
             sparse_columns = get_option("styler.sparse.columns")
 
         # Build HTML string..
-        html = self._render_html(
+        html = obj._render_html(
             sparse_index=sparse_index,
             sparse_columns=sparse_columns,
             exclude_styles=exclude_styles,
@@ -1088,6 +1090,10 @@ def _copy(self, deepcopy: bool = False) -> Styler:
             "caption",
             "uuid",
             "uuid_len",
+            "template_latex",  # also copy templates if these have been customised
+            "template_html_style",
+            "template_html_table",
+            "template_html",
         ]
         deep = [  # nested lists or dicts
             "_display_funcs",

pandas/tests/io/formats/style/test_html.py

@@ -260,7 +260,7 @@ def test_from_custom_template_style(tmpdir):
     assert result.env is not Styler.env
     assert result.template_html_style is not Styler.template_html_style
     styler = result(DataFrame({"A": [1, 2]}))
-    assert '<link rel="stylesheet" href="mystyle.css">\n\n<style' in styler.render()
+    assert '<link rel="stylesheet" href="mystyle.css">\n\n<style' in styler.to_html()
 
 
 def test_caption_as_sequence(styler):

pandas/tests/io/formats/style/test_style.py

@@ -42,7 +42,7 @@ def mi_styler(mi_df):
 def mi_styler_comp(mi_styler):
     # comprehensively add features to mi_styler
     mi_styler.uuid_len = 5
-    mi_styler.uuid = "abcde_"
+    mi_styler.uuid = "abcde"
     mi_styler.set_caption("capt")
     mi_styler.set_table_styles([{"selector": "a", "props": "a:v;"}])
     mi_styler.hide_columns()