Improve Config tests (#2163)

py-polars/tests/test_cfg.py

@@ -16,35 +16,93 @@ def environ() -> Generator:
 
 
 def test_tables(environ: None) -> None:
-    os.environ.pop("POLARS_FMT_NO_UTF8", None)
+    df = pl.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]})
 
-    assert "POLARS_FMT_NO_UTF8" not in os.environ
     pl.Config.set_ascii_tables()
-    assert os.environ["POLARS_FMT_NO_UTF8"] == "1"
+    df_asci = str(df)
+    assert (
+        df_asci == "shape: (3, 3)\n"
+        "+-----+-----+-----+\n"
+        "| a   | b   | c   |\n"
+        "| --- | --- | --- |\n"
+        "| i64 | i64 | i64 |\n"
+        "+=================+\n"
+        "| 1   | 4   | 7   |\n"
+        "|-----+-----+-----|\n"
+        "| 2   | 5   | 8   |\n"
+        "|-----+-----+-----|\n"
+        "| 3   | 6   | 9   |\n"
+        "+-----+-----+-----+"
+    )
 
     pl.Config.set_utf8_tables()
-    assert "POLARS_FMT_NO_UTF8" not in os.environ
+    df_utf8 = str(df)
+    assert (
+        df_utf8 == "shape: (3, 3)\n"
+        "┌─────┬─────┬─────┐\n"
+        "│ a   ┆ b   ┆ c   │\n"
+        "│ --- ┆ --- ┆ --- │\n"
+        "│ i64 ┆ i64 ┆ i64 │\n"
+        "╞═════╪═════╪═════╡\n"
+        "│ 1   ┆ 4   ┆ 7   │\n"
+        "├╌╌╌╌╌┼╌╌╌╌╌┼╌╌╌╌╌┤\n"
+        "│ 2   ┆ 5   ┆ 8   │\n"
+        "├╌╌╌╌╌┼╌╌╌╌╌┼╌╌╌╌╌┤\n"
+        "│ 3   ┆ 6   ┆ 9   │\n"
+        "└─────┴─────┴─────┘"
+    )
 
 
 def test_tbl_width_chars(environ: None) -> None:
+    df = pl.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]})
     pl.Config.set_tbl_width_chars(100)
-    assert os.environ["POLARS_TABLE_WIDTH"] == "100"
-    pl.Config.set_tbl_width_chars(200)
-    assert os.environ["POLARS_TABLE_WIDTH"] == "200"
+    assert max(len(line) for line in str(df).split("\n")) == 19
 
+    pl.Config.set_tbl_width_chars(15)
+    assert max(len(line) for line in str(df).split("\n")) == 15
 
-def test_tbl_cols_rows(environ: None) -> None:
-    pl.Config.set_tbl_cols(50)
-    assert os.environ["POLARS_FMT_MAX_COLS"] == "50"
-    pl.Config.set_tbl_cols(60)
-    assert os.environ["POLARS_FMT_MAX_COLS"] == "60"
+    # this will not squeezed below 13 characters, so 10 yields 13
+    pl.Config.set_tbl_width_chars(10)
+    assert max(len(line) for line in str(df).split("\n")) == 13
 
-    pl.Config.set_tbl_rows(50)
-    assert os.environ["POLARS_FMT_MAX_ROWS"] == "50"
-    pl.Config.set_tbl_rows(60)
-    assert os.environ["POLARS_FMT_MAX_ROWS"] == "60"
+
+def test_tbl_cols(environ: None) -> None:
+    df = pl.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]})
+
+    pl.Config.set_tbl_cols(1)
+    assert str(df).split("\n")[2] == "│ a   ┆ ... │"
+    pl.Config.set_tbl_cols(2)
+    assert str(df).split("\n")[2] == "│ a   ┆ ... ┆ c   │"
+    pl.Config.set_tbl_cols(3)
+    assert str(df).split("\n")[2] == "│ a   ┆ b   ┆ c   │"
+
+
+@pytest.mark.skip("not correctly implemented at the moment")
+def test_set_tbl_rows(environ: None) -> None:
+    # df = pl.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]})
+    pass
+    #
+    # pl.Config.set_tbl_rows(3)
 
 
-@pytest.mark.skip("how to test this")
 def test_string_cache(environ: None) -> None:
+
+    df1 = pl.DataFrame({"a": ["foo", "bar", "ham"], "b": [1, 2, 3]})
+    df2 = pl.DataFrame({"a": ["foo", "spam", "eggs"], "c": [3, 2, 2]})
+
+    # ensure cache is off when casting to categorical; the join will fail
+    pl.Config.unset_global_string_cache()
+    df1a = df1.with_column(pl.col("a").cast(pl.Categorical))
+    df2a = df2.with_column(pl.col("a").cast(pl.Categorical))
+    with pytest.raises(RuntimeError):
+        _ = df1a.join(df2a, on="a", how="inner")
+
+    # now turn on the cache
     pl.Config.set_global_string_cache()
+    df1b = df1.with_column(pl.col("a").cast(pl.Categorical))
+    df2b = df2.with_column(pl.col("a").cast(pl.Categorical))
+    out = df1b.join(df2b, on="a", how="inner")
+    assert out.frame_equal(pl.DataFrame({"a": ["foo"], "b": [1], "c": [3]}))
+
+    # turn off again so we do not break other tests (TODO: environ fixture does not roll this back?)
+    pl.Config.unset_global_string_cache()