CI: test-coverage

Beginne damit, den aufgeführten pytest-Coverage-Befehl für python/ und examples/tpch/_tests.py auszuführen, danach den cargo llvm-cov-Bericht für die angegebenen Rust-Quellen. Im Issue werden keine zu ändernden Dateien, Coverage-Ziele oder Abschlussbedingung angegeben, daher müssen Umfang und Definition of done geklärt werden.

For reference here's the current output for python and rust coverage.

 pytest python/ examples/tpch/_tests.py --cov=datafusion --cov-report lcov:pytest-coverage.lcov --cov-report term
---------- coverage: platform linux, python 3.11.9-final-0 -----------
Name                                               Stmts   Miss  Cover
----------------------------------------------------------------------
python/datafusion/__init__.py                         25      2    92%
python/datafusion/catalog.py                          27     10    63%
python/datafusion/common.py                           14      0   100%
python/datafusion/context.py                         192     25    87%
python/datafusion/dataframe.py                       110      6    95%
python/datafusion/expr.py                            199     32    84%
python/datafusion/functions.py                       488     34    93%
python/datafusion/input/__init__.py                    2      0   100%
python/datafusion/input/base.py                       10      2    80%
python/datafusion/input/location.py                   31     11    65%
python/datafusion/object_store.py                      8      0   100%
python/datafusion/record_batch.py                     25      3    88%
python/datafusion/substrait.py                        50      2    96%
python/datafusion/tests/__init__.py                    0      0   100%
python/datafusion/tests/conftest.py                   15      0   100%
python/datafusion/tests/generic.py                    30      0   100%
python/datafusion/tests/test_aggregation.py           46      0   100%
python/datafusion/tests/test_catalog.py               12      0   100%
python/datafusion/tests/test_config.py                15      0   100%
python/datafusion/tests/test_context.py              306      0   100%
python/datafusion/tests/test_dataframe.py            372      0   100%
python/datafusion/tests/test_expr.py                 102      0   100%
python/datafusion/tests/test_functions.py            247      0   100%
python/datafusion/tests/test_imports.py               36      0   100%
python/datafusion/tests/test_indexing.py              20      0   100%
python/datafusion/tests/test_input.py                 11      0   100%
python/datafusion/tests/test_sql.py                  184      0   100%
python/datafusion/tests/test_store.py                 16      0   100%
python/datafusion/tests/test_substrait.py             33      0   100%
python/datafusion/tests/test_udaf.py                  49     11    78%
python/datafusion/tests/test_wrapper_coverage.py      20      0   100%
python/datafusion/udf.py                              62      9    85%
----------------------------------------------------------------------
TOTAL                                               2757    147    95%
Coverage LCOV written to file pytest-coverage.lcov

+ cargo llvm-cov report
Filename                         Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
catalog.rs                            38                11    71.05%          19                 3    84.21%          61                22    63.93%           0                 0         -
common.rs                             26                12    53.85%           1                 0   100.00%          15                 0   100.00%           0                 0         -
common/data_type.rs                  286               264     7.69%          22                12    45.45%         573               537     6.28%           0                 0         -
common/df_schema.rs                    8                 6    25.00%           6                 4    33.33%          18                16    11.11%           0                 0         -
common/function.rs                     5                 4    20.00%           4                 3    25.00%          22                21     4.55%           0                 0         -
common/schema.rs                      56                45    19.64%          28                19    32.14%         108                81    25.00%           0                 0         -
config.rs                             48                19    60.42%          10                 3    70.00%          52                16    69.23%           0                 0         -
context.rs                           446               124    72.20%         103                32    68.93%         709               115    83.78%           0                 0         -
dataframe.rs                         450                90    80.00%          71                 2    97.18%         462                39    91.56%           0                 0         -
dataset.rs                            38                 9    76.32%          10                 3    70.00%          64                10    84.38%           0                 0         -
dataset_exec.rs                      150                45    70.00%          39                16    58.97%         220                33    85.00%           0                 0         -
errors.rs                             18                 9    50.00%           9                 5    44.44%          34                19    44.12%           0                 0         -
expr.rs                              321               220    31.46%          39                17    56.41%         377               236    37.40%           0                 0         -
expr/aggregate.rs                     35                24    31.43%          21                13    38.10%          89                63    29.21%           0                 0         -
expr/aggregate_expr.rs                15                12    20.00%          11                 8    27.27%          30                25    16.67%           0                 0         -
expr/alias.rs                         10                 8    20.00%           8                 6    25.00%          26                24     7.69%           0                 0         -
expr/analyze.rs                       14                12    14.29%          12                10    16.67%          32                30     6.25%           0                 0         -
expr/between.rs                       12                10    16.67%          10                 8    20.00%          34                32     5.88%           0                 0         -
expr/binary_expr.rs                   10                 3    70.00%           8                 2    75.00%          20                 6    70.00%           0                 0         -
expr/bool_expr.rs                     70                50    28.57%          50                30    40.00%         160               140    12.50%           0                 0         -
expr/case.rs                          15                13    13.33%          10                 8    20.00%          24                22     8.33%           0                 0         -
expr/cast.rs                          16                12    25.00%          12                 8    33.33%          28                24    14.29%           0                 0         -
expr/column.rs                        12                 6    50.00%           9                 4    55.56%          21                10    52.38%           0                 0         -
expr/conditional_expr.rs              15                 5    66.67%           7                 2    71.43%          19                 6    68.42%           0                 0         -
expr/create_memory_table.rs           15                13    13.33%          13                11    15.38%          46                44     4.35%           0                 0         -
expr/create_view.rs                   20                18    10.00%          14                12    14.29%          48                46     4.17%           0                 0         -
expr/cross_join.rs                    14                12    14.29%          12                10    16.67%          42                40     4.76%           0                 0         -
expr/distinct.rs                      18                16    11.11%          10                 8    20.00%          42                40     4.76%           0                 0         -
expr/drop_table.rs                    14                12    14.29%          12                10    16.67%          39                37     5.13%           0                 0         -
expr/empty_relation.rs                13                11    15.38%          11                 9    18.18%          36                34     5.56%           0                 0         -
expr/exists.rs                         7                 5    28.57%           5                 3    40.00%          11                 9    18.18%           0                 0         -
expr/explain.rs                       22                20     9.09%          13                11    15.38%          54                52     3.70%           0                 0         -
expr/extension.rs                      8                 6    25.00%           6                 4    33.33%          14                12    14.29%           0                 0         -
expr/filter.rs                        13                 7    46.15%          11                 6    45.45%          35                24    31.43%           0                 0         -
expr/grouping_set.rs                   3                 2    33.33%           3                 2    33.33%           7                 6    14.29%           0                 0         -
expr/in_list.rs                       10                 1    90.00%           7                 0   100.00%          15                 0   100.00%           0                 0         -
expr/in_subquery.rs                    8                 6    25.00%           6                 4    33.33%          14                12    14.29%           0                 0         -
expr/join.rs                          40                34    15.00%          30                24    20.00%         105                99     5.71%           0                 0         -
expr/like.rs                          36                30    16.67%          30                24    20.00%         111               105     5.41%           0                 0         -