From 234884f95f59b8eb7145987fae17cce2a78ff145 Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Tue, 9 Jul 2024 19:35:13 -0400
Subject: [PATCH 1/7] Fix index dtype override for default c engine

---
 pandas/core/indexes/base.py | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 7d43498d4267b..13c42284ff3d2 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -6379,9 +6379,11 @@ def _transform_index(self, func, *, level=None) -> Index:
         """
         if isinstance(self, ABCMultiIndex):
             values = [
-                self.get_level_values(i).map(func)
-                if i == level or level is None
-                else self.get_level_values(i)
+                (
+                    self.get_level_values(i).map(func)
+                    if i == level or level is None
+                    else self.get_level_values(i)
+                )
                 for i in range(self.nlevels)
             ]
             return type(self).from_arrays(values)
@@ -7478,7 +7480,9 @@ def ensure_index_from_sequences(sequences, names=None) -> Index:
     if len(sequences) == 1:
         if names is not None:
             names = names[0]
-        return Index(maybe_sequence_to_range(sequences[0]), name=names)
+        data = sequences[0]
+        dtype = data.dtype if isinstance(sequences[0], np.ndarray) else None
+        return Index(maybe_sequence_to_range(data), dtype=dtype, name=names)
     else:
         # TODO: Apply maybe_sequence_to_range to sequences?
         return MultiIndex.from_arrays(sequences, names=names)

From ce4b469890dcf56578390053a361e83aab20a53a Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Tue, 9 Jul 2024 19:53:30 -0400
Subject: [PATCH 2/7] Update v3.0.0 doc

---
 doc/source/whatsnew/v3.0.0.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/doc/source/whatsnew/v3.0.0.rst b/doc/source/whatsnew/v3.0.0.rst
index cd917924880f1..7731406e2fbed 100644
--- a/doc/source/whatsnew/v3.0.0.rst
+++ b/doc/source/whatsnew/v3.0.0.rst
@@ -568,6 +568,7 @@ I/O
 - Bug in :meth:`DataFrame.to_string` that raised ``StopIteration`` with nested DataFrames. (:issue:`16098`)
 - Bug in :meth:`HDFStore.get` was failing to save data of dtype datetime64[s] correctly (:issue:`59004`)
 - Bug in :meth:`read_csv` causing segmentation fault when ``encoding_errors`` is not a string. (:issue:`59059`)
+- Bug in :meth:`read_csv` not respecting ``dtype`` for ``index`` when using default c ``engine``. (:issue:`59077`)
 - Bug in :meth:`read_csv` raising ``TypeError`` when ``index_col`` is specified and ``na_values`` is a dict containing the key ``None``. (:issue:`57547`)
 - Bug in :meth:`read_csv` raising ``TypeError`` when ``nrows`` and ``iterator`` are specified without specifying a ``chunksize``. (:issue:`59079`)
 - Bug in :meth:`read_excel` raising ``ValueError`` when passing array of boolean values when ``dtype="boolean"``. (:issue:`58159`)

From 27f30396c7cdb4b26a50aac44d5f58901461861d Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Tue, 9 Jul 2024 20:08:35 -0400
Subject: [PATCH 3/7] Update test

---
 .../io/parser/dtypes/test_dtypes_basic.py     | 21 ++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/pandas/tests/io/parser/dtypes/test_dtypes_basic.py b/pandas/tests/io/parser/dtypes/test_dtypes_basic.py
index d45368dece6d2..452bd19ecbd3b 100644
--- a/pandas/tests/io/parser/dtypes/test_dtypes_basic.py
+++ b/pandas/tests/io/parser/dtypes/test_dtypes_basic.py
@@ -59,18 +59,25 @@ def test_dtype_all_columns(all_parsers, dtype, check_orig):
 def test_dtype_per_column(all_parsers):
     parser = all_parsers
     data = """\
-one,two
-1,2.5
-2,3.5
-3,4.5
-4,5.5"""
+one,two,three
+1,2.5,11
+2,3.5,12
+3,4.5,13
+4,5.5,14"""
     expected = DataFrame(
-        [[1, "2.5"], [2, "3.5"], [3, "4.5"], [4, "5.5"]], columns=["one", "two"]
+        [[1, "2.5", 11], [2, "3.5", 12], [3, "4.5", 13], [4, "5.5", 14]],
+        columns=["one", "two", "three"],
     )
     expected["one"] = expected["one"].astype(np.float64)
     expected["two"] = expected["two"].astype(object)
+    expected["three"] = expected["three"].astype(np.uint32)
+    expected.set_index("three", inplace=True)
 
-    result = parser.read_csv(StringIO(data), dtype={"one": np.float64, 1: str})
+    result = parser.read_csv(
+        StringIO(data),
+        dtype={"one": np.float64, 1: str, "three": np.uint32},
+        index_col="three",
+    )
     tm.assert_frame_equal(result, expected)
 
 

From dd83c3ddd88ee7804cd28beca1bff39eaa4605b5 Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Tue, 9 Jul 2024 23:29:56 -0400
Subject: [PATCH 4/7] Fix index dtype override for python engine

---
 doc/source/whatsnew/v3.0.0.rst     | 2 +-
 pandas/io/parsers/python_parser.py | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/doc/source/whatsnew/v3.0.0.rst b/doc/source/whatsnew/v3.0.0.rst
index 7731406e2fbed..39b5a810e3a8f 100644
--- a/doc/source/whatsnew/v3.0.0.rst
+++ b/doc/source/whatsnew/v3.0.0.rst
@@ -568,7 +568,7 @@ I/O
 - Bug in :meth:`DataFrame.to_string` that raised ``StopIteration`` with nested DataFrames. (:issue:`16098`)
 - Bug in :meth:`HDFStore.get` was failing to save data of dtype datetime64[s] correctly (:issue:`59004`)
 - Bug in :meth:`read_csv` causing segmentation fault when ``encoding_errors`` is not a string. (:issue:`59059`)
-- Bug in :meth:`read_csv` not respecting ``dtype`` for ``index`` when using default c ``engine``. (:issue:`59077`)
+- Bug in :meth:`read_csv` not respecting ``dtype`` for ``index``. (:issue:`59077`)
 - Bug in :meth:`read_csv` raising ``TypeError`` when ``index_col`` is specified and ``na_values`` is a dict containing the key ``None``. (:issue:`57547`)
 - Bug in :meth:`read_csv` raising ``TypeError`` when ``nrows`` and ``iterator`` are specified without specifying a ``chunksize``. (:issue:`59079`)
 - Bug in :meth:`read_excel` raising ``ValueError`` when passing array of boolean values when ``dtype="boolean"``. (:issue:`58159`)
diff --git a/pandas/io/parsers/python_parser.py b/pandas/io/parsers/python_parser.py
index 05fe963e9b2b7..5add1cd7e2dbc 100644
--- a/pandas/io/parsers/python_parser.py
+++ b/pandas/io/parsers/python_parser.py
@@ -309,13 +309,13 @@ def read(
         data, columns = self._exclude_implicit_index(alldata)
 
         conv_data = self._convert_data(data)
-        conv_data = self._do_date_conversions(columns, conv_data)
+        date_data = self._do_date_conversions(columns, conv_data)
 
         index, result_columns = self._make_index(
-            conv_data, alldata, columns, indexnamerow
+            date_data, list(conv_data.values()), columns, indexnamerow
         )
 
-        return index, result_columns, conv_data
+        return index, result_columns, date_data
 
     def _exclude_implicit_index(
         self,

From eb184d548440103321c0fcb958b632e8685c1c75 Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Wed, 10 Jul 2024 00:13:38 -0400
Subject: [PATCH 5/7] Fix implicit index case for python parsing

---
 pandas/io/parsers/python_parser.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pandas/io/parsers/python_parser.py b/pandas/io/parsers/python_parser.py
index 5add1cd7e2dbc..ee35b512898c2 100644
--- a/pandas/io/parsers/python_parser.py
+++ b/pandas/io/parsers/python_parser.py
@@ -311,8 +311,12 @@ def read(
         conv_data = self._convert_data(data)
         date_data = self._do_date_conversions(columns, conv_data)
 
+        if not self._implicit_index:
+            # propagate index dtype
+            alldata = list(conv_data.values())
+
         index, result_columns = self._make_index(
-            date_data, list(conv_data.values()), columns, indexnamerow
+            date_data, alldata, columns, indexnamerow
         )
 
         return index, result_columns, date_data

From 07a41abfbd9078a347c4d682d3e9dadde123b8e0 Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Wed, 10 Jul 2024 00:50:48 -0400
Subject: [PATCH 6/7] Fix implicit datetime index dtype

---
 pandas/core/indexes/base.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 13c42284ff3d2..ffd76b4c86670 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -7481,8 +7481,13 @@ def ensure_index_from_sequences(sequences, names=None) -> Index:
         if names is not None:
             names = names[0]
         data = sequences[0]
-        dtype = data.dtype if isinstance(sequences[0], np.ndarray) else None
-        return Index(maybe_sequence_to_range(data), dtype=dtype, name=names)
+        conv_data = maybe_sequence_to_range(data)
+        dtype = (
+            data.dtype
+            if isinstance(data, np.ndarray) and isinstance(conv_data, range)
+            else None
+        )
+        return Index(conv_data, dtype=dtype, name=names)
     else:
         # TODO: Apply maybe_sequence_to_range to sequences?
         return MultiIndex.from_arrays(sequences, names=names)

From ef6fc994f10046037f2aaab2eae6a6e1c1bc665b Mon Sep 17 00:00:00 2001
From: Xiaoyu <39925367+xouyang1@users.noreply.github.com>
Date: Wed, 10 Jul 2024 02:14:17 -0400
Subject: [PATCH 7/7] Ignore known mypy issue for np array

---
 pandas/io/parsers/python_parser.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/parsers/python_parser.py b/pandas/io/parsers/python_parser.py
index ee35b512898c2..e3002afd46c5d 100644
--- a/pandas/io/parsers/python_parser.py
+++ b/pandas/io/parsers/python_parser.py
@@ -313,7 +313,7 @@ def read(
 
         if not self._implicit_index:
             # propagate index dtype
-            alldata = list(conv_data.values())
+            alldata = list(conv_data.values())  # type: ignore[arg-type]
 
         index, result_columns = self._make_index(
             date_data, alldata, columns, indexnamerow