Report nested elements in C# XML text

[mristin]

The C# de-serialization threw an InvalidOperationException instead of reporting an error when the content of a primitive started with an element, e.g., <someString><nested/></someString>. XmlReader.ReadContentAs* throws it at an element node, and our catch filters did not cover it. We now check for an element before the conversion in AsText, which all the primitives go through:

if (reader.NodeType == Xml.XmlNodeType.Element)
{
    error = new Reporting.Error(
        $"Expected an XML content representing {typeof(T).Name}, " +
        $"but got a nested element {reader.Name}");
    return default!;
}

The XML-RPC readers of <boolean>, <double> and <string> had the same bug, and get the same check. Moreover, the key of a struct member was coalesced with ?? throw before the error was checked, so any error in a <name> surfaced as an InvalidOperationException. We now check the error first.

We add the live test data some_string_as_nested_element.xml for all the targets, and a C# XML-RPC test with a nested element in <boolean>, <double>, <string> and <name>.

[coveralls]

Coverage Report for CI Build 38185248312

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Coverage remained the same at 90.141%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	50217
Covered Lines:	45266
Line Coverage:	90.14%
Coverage Strength:	2.7 hits per line

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