CI type check `mypy` is failing

[ToastCheng]

Describe the issue

When uploading the PR #7655, I found this failure that is irrelevant to my change.

cirq-core/cirq/transformers/heuristic_decompositions/two_qubit_gate_tabulation.py:112: error: Need type annotation for "inner_gates"  [var-annotated]
cirq-core/cirq/linalg/transformations.py:85: error: Argument "key" to "max" has incompatible type "Callable[[tuple[Any, ...]], ndarray[tuple[Any, ...], dtype[floating[Any]]]]"; expected "Callable[[tuple[Any, ...]], SupportsDunderLT[Any] | SupportsDunderGT[Any]]"  [arg-type]
cirq-core/cirq/linalg/transformations.py:85: error: Incompatible return value type (got "ndarray[tuple[Any, ...], dtype[floating[Any]]]", expected "SupportsDunderLT[Any] | SupportsDunderGT[Any]")  [return-value]
cirq-core/cirq/ops/clifford_gate.py:642: error: Argument "key" to "max" has incompatible type "Callable[[tuple[Any, ...]], ndarray[tuple[Any, ...], dtype[floating[Any]]]]"; expected "Callable[[tuple[Any, ...]], SupportsDunderLT[Any] | SupportsDunderGT[Any]]"  [arg-type]
cirq-core/cirq/ops/clifford_gate.py:642: error: Incompatible return value type (got "ndarray[tuple[Any, ...], dtype[floating[Any]]]", expected "SupportsDunderLT[Any] | SupportsDunderGT[Any]")  [return-value]
cirq-core/cirq/sim/clifford/stabilizer_state_ch_form.py:291: error: Unused "type: ignore" comment  [unused-ignore]
cirq-core/cirq/sim/clifford/stabilizer_state_ch_form.py:292: error: Unused "type: ignore" comment  [unused-ignore]
cirq-core/cirq/sim/clifford/stabilizer_state_ch_form.py:293: error: Unused "type: ignore" comment  [unused-ignore]
cirq-core/cirq/sim/clifford/stabilizer_state_ch_form.py:294: error: Unused "type: ignore" comment  [unused-ignore]
cirq-core/cirq/sim/state_vector_simulation_state_test.py:120: error: Argument "dtype" to "StateVectorSimulationState" has incompatible type "dtype[Any]"; expected "type[complexfloating[Any, Any]]"  [arg-type]
cirq-core/cirq/sim/state_vector_simulation_state_test.py:139: error: Argument "dtype" to "StateVectorSimulationState" has incompatible type "dtype[Any]"; expected "type[complexfloating[Any, Any]]"  [arg-type]
Found 11 errors in 5 files (checked 1126 source files)

This failure can be reproduced locally as well, and I don't see any recent changes on the failing files, CI configuration etc.

One thing to note is that the type check only fails in the latest CI run on my PR, it's PASS in the previous round:

• FAIL: https://github.com/quantumlib/Cirq/actions/runs/17844613705/job/50741471717
• PASS: https://github.com/quantumlib/Cirq/actions/runs/17834763837/job/50709006575

The difference between the two commit is just the commit message.

Explain how to reproduce the bug or problem

It is failing on CI, and also locally:

./check/mypy

Put long logs in HTML details blocks like this.

Tell us the version of Cirq where this happens

From latest source code

python -c 'import cirq; print(cirq.__version__)'
1.6.1

[ToastCheng]

I found that it's similar to #7323, so I checked the dependencies version between the passing log and failing log:

• Passed log from CI
• Failed log from CI

The numpy version did changed from 2.2.6 to 2.3.3. Trying to verify if this is the root cause, I modified the cirq-core/requirements.txt to use the old version, and reinstall numpy:

numpy==2.2.6

Now check/mypy can pass locally.

[mhucka]

@ToastCheng a change (#7661) merged by @pavoljuhas into the main branch today should fix this issue. I will close this issue; however, if you still experience problems, please feel free to reopen this.