[Data] Fix: Replace bare raise with TypeError in string concatenation by slfan1989 · Pull Request #60795 · ray-project/ray

slfan1989 · 2026-02-06T01:40:52Z

Description

This PR fixes a bug in _to_pa_string_input() where attempting to concatenate string columns with non-string columns (e.g., numeric types) would raise a bare RuntimeError instead of a descriptive TypeError.

Changes:

Replaced bare raise statement with proper TypeError that includes a clear error message indicating expected vs actual input types
Simplified control flow using early returns
Added unit test test_string_concat_invalid_input_type to verify the fix

Before: Bare raise caused cryptic RuntimeError: No active exception to reraise

After: Clear TypeError: Expected string or string-like pyarrow Array/ChunkedArray for string concatenation, got int64.

Related issues

Link related issues: "Fixes #1234", "Closes #1234", or "Related to #1234".

Additional information

Example of the fixed behavior:

import pyarrow as pa
from ray.data.expressions import col

table = pa.table({"name": ["Alice", "Bob"], "age": [25, 30]})
expr = col("name") + col("age")  # Attempting to concat string with int

# Now raises: TypeError: Expected string or string-like pyarrow Array/ChunkedArray 
# for string concatenation, got int64.

Replace the bare `raise` statement in `_to_pa_string_input()` with a proper TypeError that includes a descriptive error message. This ensures string concatenation operations fail with clear feedback when given non-string inputs (e.g., numeric columns). Changes: - expression_evaluator.py: Add TypeError with descriptive message - test_arithmetic.py: Add test for invalid input type rejection Signed-off-by: slfan1989 <slfan1989@apache.org>

gemini-code-assist

Code Review

This pull request is a solid improvement, replacing a bare raise with a descriptive TypeError for invalid string concatenation operations. The code is also simplified by using early returns. I've added one suggestion to make the error message even more informative by including the specific data type of the invalid input, which aligns with the goal stated in the pull request description. The new unit test is a great addition to prevent regressions.

gemini-code-assist · 2026-02-06T01:48:09Z

+    raise TypeError(
+        "Expected string or string-like pyarrow Array/ChunkedArray for string "
+        f"concatenation, got {type(x).__name__}."
+    )


The error message can be made more specific to better align with the goal stated in the PR description. When x is a pyarrow.Array or pyarrow.ChunkedArray, using x.type instead of type(x).__name__ will provide the underlying data type (e.g., int64), which is more informative for debugging.

Suggested change

raise TypeError(

"Expected string or string-like pyarrow Array/ChunkedArray for string "

f"concatenation, got {type(x).__name__}."

)

type_name = x.type if isinstance(x, (pa.Array, pa.ChunkedArray)) else type(x).__name__

raise TypeError(

"Expected string or string-like pyarrow Array/ChunkedArray for string "

f"concatenation, got {type_name}."

)

cursor

Cursor Bugbot has reviewed your changes and found 1 potential issue.

Replace the bare `raise` statement in `_to_pa_string_input()` with a proper TypeError that includes a descriptive error message. This ensures string concatenation operations fail with clear feedback when given non-string inputs (e.g., numeric columns). Changes: - expression_evaluator.py: Add TypeError with descriptive message - test_arithmetic.py: Add test for invalid input type rejection Signed-off-by: slfan1989 <slfan1989@apache.org>

goutamvenkat-anyscale · 2026-02-06T20:59:49Z

+    if isinstance(x, (pa.Array, pa.ChunkedArray)) and _is_pa_string_like(x):
+        return _pa_decode_dict_string_array(x)
+    if isinstance(x, (pa.Array, pa.ChunkedArray)):
+        actual_type = str(x.type)
    else:
-        raise
-    return x
+        actual_type = type(x).__name__
+    raise TypeError(
+        "Expected string or string-like pyarrow Array/ChunkedArray for string "
+        f"concatenation, got {actual_type}."
+    )


Suggested cleanup:

if isinstance(x, (pa.Array, pa.ChunkedArray)) and _is_pa_string_like(x): return _pa_decode_dict_string_array(x) actual_type = str(x.type) if isinstance(x, (pa.Array, pa.ChunkedArray)) else type(x).__name__ raise TypeError( "Expected string or string-like pyarrow Array/ChunkedArray for string " f"concatenation, got {actual_type}." )

Thanks for the suggestions! I’ve updated the PR accordingly—could you please take another look?

Replace the bare `raise` statement in `_to_pa_string_input()` with a proper TypeError that includes a descriptive error message. This ensures string concatenation operations fail with clear feedback when given non-string inputs (e.g., numeric columns). Changes: - expression_evaluator.py: Add TypeError with descriptive message - test_arithmetic.py: Add test for invalid input type rejection Signed-off-by: slfan1989 <slfan1989@apache.org>

slfan1989 · 2026-02-10T21:15:29Z

@goutamvenkat-anyscale @bveeramani Could you please review this PR again? Thank you very much!

bveeramani · 2026-02-10T23:33:22Z

@goutamvenkat-anyscale @bveeramani Could you please review this PR again? Thank you very much!

Will defer to @goutamvenkat-anyscale since he has more context on this PR

slfan1989 · 2026-02-10T23:39:16Z

@goutamvenkat-anyscale @bveeramani Could you please review this PR again? Thank you very much!

Will defer to @goutamvenkat-anyscale since he has more context on this PR

Thanks a lot for your reply!

goutamvenkat-anyscale

lgtm!

slfan1989 · 2026-02-11T21:08:42Z

@goutamvenkat-anyscale @bveeramani Thank you very much for reviewing the code!

…ray-project#60795) ## Description This PR fixes a bug in `_to_pa_string_input()` where attempting to concatenate string columns with non-string columns (e.g., numeric types) would raise a bare `RuntimeError` instead of a descriptive `TypeError`. **Changes:** - Replaced bare `raise` statement with proper `TypeError` that includes a clear error message indicating expected vs actual input types - Simplified control flow using early returns - Added unit test `test_string_concat_invalid_input_type` to verify the fix **Before:** Bare `raise` caused cryptic `RuntimeError: No active exception to reraise` **After:** Clear `TypeError: Expected string or string-like pyarrow Array/ChunkedArray for string concatenation, got int64.` ## Related issues > Link related issues: "Fixes ray-project#1234", "Closes ray-project#1234", or "Related to ray-project#1234". ## Additional information **Example of the fixed behavior:** ```python import pyarrow as pa from ray.data.expressions import col table = pa.table({"name": ["Alice", "Bob"], "age": [25, 30]}) expr = col("name") + col("age") # Attempting to concat string with int # Now raises: TypeError: Expected string or string-like pyarrow Array/ChunkedArray # for string concatenation, got int64. ``` --------- Signed-off-by: slfan1989 <slfan1989@apache.org> Signed-off-by: Adel Nour <ans9868@nyu.edu>

…ray-project#60795) ## Description This PR fixes a bug in `_to_pa_string_input()` where attempting to concatenate string columns with non-string columns (e.g., numeric types) would raise a bare `RuntimeError` instead of a descriptive `TypeError`. **Changes:** - Replaced bare `raise` statement with proper `TypeError` that includes a clear error message indicating expected vs actual input types - Simplified control flow using early returns - Added unit test `test_string_concat_invalid_input_type` to verify the fix **Before:** Bare `raise` caused cryptic `RuntimeError: No active exception to reraise` **After:** Clear `TypeError: Expected string or string-like pyarrow Array/ChunkedArray for string concatenation, got int64.` ## Related issues > Link related issues: "Fixes ray-project#1234", "Closes ray-project#1234", or "Related to ray-project#1234". ## Additional information **Example of the fixed behavior:** ```python import pyarrow as pa from ray.data.expressions import col table = pa.table({"name": ["Alice", "Bob"], "age": [25, 30]}) expr = col("name") + col("age") # Attempting to concat string with int # Now raises: TypeError: Expected string or string-like pyarrow Array/ChunkedArray # for string concatenation, got int64. ``` --------- Signed-off-by: slfan1989 <slfan1989@apache.org>

slfan1989 requested a review from a team as a code owner February 6, 2026 01:40

gemini-code-assist Bot reviewed Feb 6, 2026

View reviewed changes

cursor Bot reviewed Feb 6, 2026

View reviewed changes

Comment thread python/ray/data/_internal/planner/plan_expression/expression_evaluator.py

ray-gardener Bot added the community-contribution Contributed by the community label Feb 6, 2026

goutamvenkat-anyscale reviewed Feb 6, 2026

View reviewed changes

slfan1989 and others added 2 commits February 7, 2026 07:10

Merge branch 'master' into fix/pa-string-input-typeerror

cd061f6

Merge branch 'master' into fix/pa-string-input-typeerror

9d9e136

goutamvenkat-anyscale approved these changes Feb 11, 2026

View reviewed changes

goutamvenkat-anyscale added go add ONLY when ready to merge, run all tests data Ray Data-related issues labels Feb 11, 2026

bveeramani enabled auto-merge (squash) February 11, 2026 20:02

bveeramani merged commit 12e3e50 into ray-project:master Feb 11, 2026
8 checks passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

[Data] Fix: Replace bare raise with TypeError in string concatenation#60795

[Data] Fix: Replace bare raise with TypeError in string concatenation#60795
bveeramani merged 5 commits into
ray-project:masterfrom
slfan1989:fix/pa-string-input-typeerror

slfan1989 commented Feb 6, 2026

gemini-code-assist Bot left a comment

gemini-code-assist Bot Feb 6, 2026

cursor Bot left a comment

Uh oh!

goutamvenkat-anyscale Feb 6, 2026

slfan1989 Feb 6, 2026

slfan1989 commented Feb 10, 2026

bveeramani commented Feb 10, 2026

slfan1989 commented Feb 10, 2026

goutamvenkat-anyscale left a comment

Uh oh!

slfan1989 commented Feb 11, 2026

Labels

3 participants

Uh oh!

Conversation

slfan1989 commented Feb 6, 2026

Description

Related issues

Additional information

gemini-code-assist Bot left a comment

Choose a reason for hiding this comment

Code Review

gemini-code-assist Bot Feb 6, 2026

Choose a reason for hiding this comment

cursor Bot left a comment

Choose a reason for hiding this comment

Uh oh!

goutamvenkat-anyscale Feb 6, 2026

Choose a reason for hiding this comment

slfan1989 Feb 6, 2026

Choose a reason for hiding this comment

slfan1989 commented Feb 10, 2026

bveeramani commented Feb 10, 2026

slfan1989 commented Feb 10, 2026

goutamvenkat-anyscale left a comment

Choose a reason for hiding this comment

Uh oh!

slfan1989 commented Feb 11, 2026

Labels

3 participants