TST: run python-dev CI on 3.14-dev

[ngoldbaum]

I'd like to see how widespread the test breakage is due to #61368.

Also 3.14rc1 came out earlier this week so Pandas should probably start thinking about 3.14 support soonish.

[ngoldbaum]

After turning off the warning the tests results look much more reasonable. Here's the summary on Linux CI:

=========================== short test summary info ============================
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_series_setitem[0] - Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) were emitted.
 Emitted warnings: [].
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_series_setitem[indexer1] - Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) were emitted.
 Emitted warnings: [].
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_series_setitem[indexer2] - Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) were emitted.
 Emitted warnings: [].
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_series_setitem[indexer3] - Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) were emitted.
 Emitted warnings: [].
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_frame_setitem[a] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_frame_setitem[indexer1] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_frame_setitem[indexer2] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_chained_assignment_deprecation.py::test_frame_setitem[indexer3] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_clip.py::test_clip_chained_inplace - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_interp_fillna.py::test_fillna_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_interp_fillna.py::test_interpolate_chained_assignment[interpolate] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_interp_fillna.py::test_interpolate_chained_assignment[ffill] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_interp_fillna.py::test_interpolate_chained_assignment[bfill] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_methods.py::test_chained_where_mask[mask] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_methods.py::test_chained_where_mask[where] - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_methods.py::test_update_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/copy_view/test_replace.py::test_replace_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/reshape/merge/test_merge.py::test_merge_suffix_length_error[a-a-suffixes0-too many values to unpack \\(expected 2\\)] - AssertionError: Regex pattern did not match.
 Regex: 'too many values to unpack \\(expected 2\\)'
 Input: 'too many values to unpack (expected 2, got 3)'
FAILED pandas/tests/scalar/period/test_period.py::TestPeriodConstruction::test_invalid_arguments - AssertionError: Regex pattern did not match.
 Regex: 'day is out of range for month'
 Input: 'day 0 must be in range 1..31 for month 1 in year 1: 0'
FAILED pandas/tests/scalar/timestamp/test_constructors.py::TestTimestampConstructorPositionalAndKeywordSupport::test_constructor_positional - AssertionError: Regex pattern did not match.
 Regex: 'day is out of range for month'
 Input: 'day 0 must be in range 1..31 for month 1 in year 2000'
FAILED pandas/tests/scalar/timestamp/test_constructors.py::TestTimestampConstructorPositionalAndKeywordSupport::test_constructor_keyword - AssertionError: Regex pattern did not match.
 Regex: 'day is out of range for month'
 Input: 'day 0 must be in range 1..31 for month 1 in year 2000'
FAILED pandas/tests/series/accessors/test_dt_accessor.py::TestSeriesDatetimeValues::test_dt_accessor_not_writeable - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/series/indexing/test_indexing.py::test_underlying_data_conversion - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/series/methods/test_update.py::TestUpdate::test_update - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexes/test_indexing.py::TestContains::test_contains_requires_hashable_raises[interval] - AssertionError: Regex pattern did not match.
 Regex: "unhashable type: 'dict'|must be real number, not dict|an integer is required|\\{\\}|pandas\\._libs\\.interval\\.IntervalTree' is not iterable"
 Input: "argument of type 'pandas._libs.interval.IntervalTree' is not a container or iterable"
FAILED pandas/tests/indexing/multiindex/test_chaining_and_caching.py::test_detect_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/multiindex/test_chaining_and_caching.py::test_cache_updating - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/multiindex/test_partial.py::TestMultiIndexPartial::test_partial_set - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/multiindex/test_setitem.py::test_frame_setitem_copy_raises - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/multiindex/test_setitem.py::test_frame_setitem_copy_no_write - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestCaching::test_setitem_cache_updating_slices - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_setitem_chained_setfault - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_raises - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_fails - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_doc_example - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_object_dtype - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_undefined_column - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_changing_dtype - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_setting_with_copy_bug - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_detect_chained_assignment_warnings_errors - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_iloc_setitem_chained_assignment - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/indexing/test_chaining_and_caching.py::TestChaining::test_getitem_loc_assignment_slice_state - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/tools/test_to_datetime.py::TestToDatetime::test_datetime_invalid_scalar[None-00:01:99] - AssertionError: Regex pattern did not match.
 Regex: '^time data "a" doesn\\\'t match format "%H:%M:%S". You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\\'ISO8601\\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\\'mixed\\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$|^Given date string "a" not likely a datetime$|^unconverted data remains when parsing with format "%H:%M:%S": "9". You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\\'ISO8601\\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\\'mixed\\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$|^second must be in 0..59: 00:01:99$'
 Input: 'second must be in 0..59, not 99: 00:01:99'
FAILED pandas/tests/tools/test_to_datetime.py::TestToDatetime::test_datetime_invalid_index[None-values1] - AssertionError: Regex pattern did not match.
 Regex: '^Given date string "a" not likely a datetime$|^time data "a" doesn\\\'t match format "%H:%M:%S". You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\\'ISO8601\\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\\'mixed\\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$|^unconverted data remains when parsing with format "%H:%M:%S": "9". You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\\'ISO8601\\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\\'mixed\\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$|^second must be in 0..59: 00:01:99$'
 Input: 'second must be in 0..59, not 99: 00:01:99'
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise[True] - AssertionError: Regex pattern did not match.
 Regex: 'day is out of range for month: 2015-02-29'
 Input: 'day 29 must be in range 1..28 for month 2 in year 2015: 2015-02-29'
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise[False] - AssertionError: Regex pattern did not match.
 Regex: 'day is out of range for month: 2015-02-29'
 Input: 'day 29 must be in range 1..28 for month 2 in year 2015: 2015-02-29'
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[True-2015-02-29-%Y-%m-%d-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 29 must be in range 1..28 for month 2 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[True-2015-29-02-%Y-%d-%m-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 29 must be in range 1..28 for month 2 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[True-2015-04-31-%Y-%m-%d-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 31 must be in range 1..30 for month 4 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[True-2015-31-04-%Y-%d-%m-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 31 must be in range 1..30 for month 4 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[False-2015-02-29-%Y-%m-%d-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 29 must be in range 1..28 for month 2 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[False-2015-29-02-%Y-%d-%m-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 29 must be in range 1..28 for month 2 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[False-2015-04-31-%Y-%m-%d-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 31 must be in range 1..30 for month 4 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/tools/test_to_datetime.py::TestDaysInMonth::test_day_not_in_month_raise_value[False-2015-31-04-%Y-%d-%m-^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$] - AssertionError: Regex pattern did not match.
 Regex: "^day is out of range for month. You might want to try:\\n    - passing `format` if your strings have a consistent format;\\n    - passing `format=\\'ISO8601\\'` if your strings are all ISO8601 but not necessarily in exactly the same format;\\n    - passing `format=\\'mixed\\'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this.$"
 Input: "day 31 must be in range 1..30 for month 4 in year 2015. You might want to try:\n    - passing `format` if your strings have a consistent format;\n    - passing `format='ISO8601'` if your strings are all ISO8601 but not necessarily in exactly the same format;\n    - passing `format='mixed'`, and the format will be inferred for each element individually. You might want to use `dayfirst` alongside this."
FAILED pandas/tests/frame/indexing/test_setitem.py::TestDataFrameSetitemCopyViewSemantics::test_setitem_column_update_inplace - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/frame/indexing/test_xs.py::TestXS::test_xs_view - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/frame/methods/test_fillna.py::TestFillNA::test_fillna_on_column_view - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/frame/methods/test_interpolate.py::TestDataFrameInterpolate::test_interp_inplace - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/util/test_show_versions.py::test_show_versions - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/util/test_show_versions.py::test_json_output_match - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/io/parser/test_quoting.py::test_bad_quote_char[python-kwargs0-"quotechar" must be a(n)? 1-character string] - AssertionError: Regex pattern did not match.
 Regex: '"quotechar" must be a(n)? 1-character string'
 Input: '"quotechar" must be a unicode character or None, not a string of length 3'
FAILED pandas/tests/io/parser/test_quoting.py::test_bad_quote_char[python-kwargs2-"quotechar" must be string( or None)?, not int] - AssertionError: Regex pattern did not match.
 Regex: '"quotechar" must be string( or None)?, not int'
 Input: '"quotechar" must be a unicode character or None, not int'
FAILED pandas/tests/io/parser/test_quoting.py::test_null_quote_char[python--0] - AssertionError: Regex pattern did not match.
 Regex: '"quotechar" must be a 1-character string'
 Input: '"quotechar" must be a unicode character or None, not a string of length 0'
FAILED pandas/tests/io/test_common.py::test_codecs_encoding[csv-None] - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/io/test_common.py::test_codecs_encoding[csv-utf-8] - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/io/test_common.py::test_codecs_encoding[json-None] - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/io/test_common.py::test_codecs_encoding[json-utf-8] - DeprecationWarning: codecs.open() is deprecated. Use open() instead.
FAILED pandas/tests/frame/test_block_internals.py::TestDataFrameBlockInternals::test_stale_cached_series_bug_473 - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/frame/test_block_internals.py::test_update_inplace_sets_valid_block_values - AssertionError: Did not see expected warning of class 'ChainedAssignmentError'
FAILED pandas/tests/generic/test_generic.py::TestGeneric::test_nonzero[DataFrame] - ValueError: The truth value of a DataFrame is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
FAILED pandas/tests/generic/test_generic.py::TestGeneric::test_nonzero[Series] - ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
= 72 failed, 167066 passed, 24154 skipped, 781 xfailed, 83 xpassed, 31 warnings in 453.44s (0:07:33) =

Besides the tests looking for warnings but not seeing any, I see some failures due to new deprecations in Python, some that look like changes in the regex and datetime modules maybe and a few other failures that I can't classify just looking at the failure report.

@jorisvandenbossche did you ever have time to look closer at generating the chained assignment warning on 3.14 since it was reported in April? Unfortunately we're probably past the time when we can get C API changes merged into CPython to support this use-case, so it may not be easily feasible to detect what you're looking for just based on refcounts in 3.14 and newer.