Fixes two edge cases with the mapping of double types

[michelebastione]

Mirrors PR #886 on the maintenance branch

[gemini-code-assist]

Summary of Changes

Hello @michelebastione, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request refines the handling of double type conversions within the TypeHelper utility. It introduces a more robust parsing mechanism that first attempts culture-specific conversion, then falls back to invariant culture, and finally throws an explicit exception for values that cannot be reliably converted. This change aims to prevent silent data corruption and provide clearer feedback when invalid data is encountered during type mapping.

Highlights

• Improved Double Parsing Logic: The ConvertDynamicToSpecificType method now prioritizes parsing double values using the config.Culture before falling back to CultureInfo.InvariantCulture.
• Enhanced Error Handling for Double Conversion: Unparseable string values that cannot be converted to a double (even with invariant culture) will now throw an InvalidCastException instead of silently returning double.NaN.

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[gemini-code-assist]

Code Review

This pull request addresses two edge cases in mapping double types. It now correctly uses the configured culture for parsing and throws an InvalidCastException on failure, which is more consistent with how other types are handled. The logic is sound. I've provided one suggestion to improve the readability of the new code.

[gemini-code-assist]

The logic here is correct, but the nested structure combined with a ternary expression using throw can be a bit dense and harder to read. Refactoring this to a more standard if-else structure would improve code clarity and maintainability without altering the functionality.

                if (double.TryParse(Convert.ToString(itemValue, config.Culture), NumberStyles.Any, config.Culture, out var doubleValue))
                {
                    newValue = doubleValue;
                }
                else
                {
                    var invariantString = Convert.ToString(itemValue, CultureInfo.InvariantCulture);
                    if (double.TryParse(invariantString, NumberStyles.Any, CultureInfo.InvariantCulture, out var value))
                    {
                        newValue = value;
                    }
                    else
                    {
                        throw new InvalidCastException($"Value \"{itemValue}\" cannot be cast to double");
                    }
                }