fix(hosting-cli): make ScaleParams.as_json() side-effect free

[BABTUNA]

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Type of change

• Bug fix (non-breaking change which fixes an issue)

Changes To Core Features:

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Description

ScaleParams.as_json() was mutating self.type when the type was unset:

• previous behavior: if self.type is None: self.type = ScaleType.REGION

This made serialization stateful and introduced side effects for callers reusing the same ScaleParams object.

This patch makes serialization pure by using a local effective_type variable:

• effective_type = self.type or ScaleType.REGION

No object fields are mutated during as_json().

Tests

Added regression test:

• test_scale_params_as_json_is_pure_when_type_is_unspecified

The test verifies:

• repeated as_json() calls are idempotent
• scale_params.type remains None after serialization

Validation

• uv run ruff check packages/reflex-hosting-cli/src/reflex_cli/utils/hosting.py tests/units/reflex_cli/utils/test_hosting.py
• uv run pytest tests/units/reflex_cli/utils/test_hosting.py -q
• uv run pytest tests/units/reflex_cli/v2/test_apps.py -k scale -q

Follow-up to #6369

[greptile-apps]

Greptile Summary

This PR fixes a side-effect in ScaleParams.as_json() that mutated self.type to ScaleType.REGION when it was None, making the method non-idempotent and surprising for callers reusing the same instance. The fix introduces a local effective_type variable so serialization is now pure. A focused regression test validates both idempotency and that the field is left unmutated.

Confidence Score: 5/5

Safe to merge — minimal, targeted fix with a direct regression test and no logic changes beyond removing the mutation.

The change is a one-line, obviously correct substitution of a local variable for a mutating assignment. The regression test directly exercises both properties (immutability of the field, idempotency of output). No other code paths are affected.

No files require special attention.

Important Files Changed

Filename	Overview
packages/reflex-hosting-cli/src/reflex_cli/utils/hosting.py	Replaces in-place mutation of self.type with a local effective_type variable, making as_json() side-effect free.
tests/units/reflex_cli/utils/test_hosting.py	Adds a regression test verifying that as_json() is idempotent and leaves ScaleParams.type unmutated when it is None.

Sequence Diagram

sequenceDiagram
    participant Caller
    participant ScaleParams

    Note over Caller,ScaleParams: Before fix (mutating)
    Caller->>ScaleParams: as_json() [type=None]
    ScaleParams->>ScaleParams: self.type = ScaleType.REGION
    ScaleParams-->>Caller: {"type": "region", ...}
    Caller->>ScaleParams: as_json() [type=REGION now!]
    ScaleParams-->>Caller: {"type": "region", ...}

    Note over Caller,ScaleParams: After fix (pure)
    Caller->>ScaleParams: as_json() [type=None]
    ScaleParams->>ScaleParams: effective_type = REGION (local only)
    ScaleParams-->>Caller: {"type": "region", ...}
    Caller->>ScaleParams: as_json() [type=None still]
    ScaleParams->>ScaleParams: effective_type = REGION (local only)
    ScaleParams-->>Caller: {"type": "region", ...}

Loading

_{Reviews (1): Last reviewed commit: "fix(hosting-cli): keep ScaleParams.as_js..." | Re-trigger Greptile}

[codspeed-hq]

Merging this PR will not alter performance

✅ 9 untouched benchmarks

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_{Comparing BABTUNA:fix-hosting-cli-scaleparams-pure (ff48f3a) with main (8f7ad9a)}