[Json] Remove unnecessary Debug.Asserts

[BrennanConroy]

These Debug.Asserts are over-aggressive. It's perfectly valid to do something like JsonSerializer.Deserialize<JsonArray>("\"str\":\"value\"");. And we will get a JsonException in non-debug builds.

[Copilot]

Pull Request Overview

This PR removes unnecessary Debug.Assert calls from the JsonObjectConverter and JsonArrayConverter, streamlining error handling in debug builds.

• Removed Debug.Assert from JsonObjectConverter to simplify the handling of unexpected token types.
• Removed Debug.Assert from JsonArrayConverter to align behavior with throwing exceptions on invalid token types.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Converters/Node/JsonObjectConverter.cs	Removed a Debug.Assert call in the default case for invalid JSON tokens.
src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Converters/Node/JsonArrayConverter.cs	Removed a Debug.Assert call in the default case for invalid JSON tokens.

Comments suppressed due to low confidence (2)

src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Converters/Node/JsonObjectConverter.cs:71

• The removal of Debug.Assert improves clarity and consistency by relying solely on exception throwing for invalid token types. Ensure that thorough tests cover this error path across build configurations.

                default:

src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Converters/Node/JsonArrayConverter.cs:33

• Removing Debug.Assert here aligns the error handling mechanism with that of JsonObjectConverter. Verify that the associated test coverage for invalid JSON arrays is sufficient in both debug and non-debug builds.

                default:

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[PranavSenthilnathan]

Looks like this case being reachable is intentional, so the assert should be fine to remove.

Based on git history, it looks like initially JsonNodeConverter was used to deserialize JsonArray and ensured only JSON arrays got to the Write method. Later JsonArrayConverter was added to the metadata services so any JSON value can get here if it's being deserialized as a JsonArray.

[stephentoub]

/ba-g dead lettered queue