feat(python)!: Change data orientation inference logic for DataFrame construction and warn when row orientation is inferred

[stinodego]

Closes #16818

Changes

• No longer inspect data types to infer data orientation. Data orientation is inferred based on the data and schema dimensions. This is a breaking change. See example below.
• If row orientation is inferred, issue a DataOrientationWarning. This attends the user that they are relying on 'implicit' behavior and that explicitly setting the orientation may be beneficial.

This is a bit of a hit in ergonomics in favor of explicitness.

We can infer the data orientation in some cases but not others (e.g. when number of rows/columns is equal). This ended up with surprising behavior in certain cases (see linked issue).

Our solution is to issue a warning whenever row-orientation is inferred. The user must explicitly pass orient="row" to silence the warning.

Example

Before:

>>> data = [[1, "a"], [2, "b"]]
>>> pl.DataFrame(data)
shape: (2, 2)
┌──────────┬──────────┐
│ column_0 ┆ column_1 │
│ ---      ┆ ---      │
│ i64      ┆ str      │
╞══════════╪══════════╡
│ 1        ┆ a        │
│ 2        ┆ b        │
└──────────┴──────────┘

After:

>>> pl.DataFrame(data)
Traceback (most recent call last):
...
TypeError: unexpected value while building Series of type Int64; found value of type String: "a"

Hint: Try setting `strict=False` to allow passing data with mixed types.

Use instead:

>>> pl.DataFrame(data, orient="row")
shape: (2, 2)
┌──────────┬──────────┐
│ column_0 ┆ column_1 │
│ ---      ┆ ---      │
│ i64      ┆ str      │
╞══════════╪══════════╡
│ 1        ┆ a        │
│ 2        ┆ b        │
└──────────┴──────────┘

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.03%. Comparing base (308df5d) to head (49e1b6c).

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16976      +/-   ##
==========================================
+ Coverage   81.02%   81.03%   +0.01%     
==========================================
  Files        1446     1446              
  Lines      190424   190421       -3     
  Branches     2709     2708       -1     
==========================================
+ Hits       154295   154314      +19     
+ Misses      35632    35610      -22     
  Partials      497      497              

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