PR for #2006 to test in AppVeyor.

[garethsb]

PR for #2006 to test in AppVeyor as requested by @t-b.

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Pull request checklist

Read the Contribution Guidelines for detailed information.

• Changes are described in the pull request, or an existing issue is referenced.
• The test suite compiles and runs without error.
• Code coverage is 100%. Test cases can be added by editing the test suite.
• The source code is amalgamated; that is, after making changes to the sources in the include/nlohmann directory, run make amalgamate to create the single-header file single_include/nlohmann/json.hpp. The whole process is described here.

[garethsb]

Sure enough, the AppVeyor Visual Studio 2015 build and test job passed. Either the tests are not sufficient to demonstrate the original problem, or it has been independently fixed by other changes (or a VS 2015 update?).

[t-b]

Looking at https://ci.appveyor.com/project/nlohmann/json/builds/31680408/job/s1dryqoqfjcehkln gives Microsoft (R) Build Engine version 16.5.0+d4cbfca49 for .NET Framework which shows that this indeed fixes the issue.

So I think this is ready to go.

[dota17]

I had checked and tested in my fork repo.
After merging this PR, the Appveyor CI will pass.

[emmenlau]

I can confirm that this fixes the issue for us, so we can build 3.7.3 after applying this PR with VS2019 release 5.2. Thanks!

[emmenlau]

Dear admins, I think the Travis build report is incorrect. In the details I see all jobs as completed and one failed. However this page still lists Travis as "pending".
Is there something that needs to be done?

[nlohmann]

Looks good to me.

[nlohmann]

Thanks!

[nlohmann]

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🔖 Release item

This issue/PR will be part of the next release of the library. This template helps preparing the release notes.

Type

• ✨ New Feature
• 🐛 Bug Fix
• ⚡️ Improvement
• 🔨 Further Change
• 🔥 Deprecated function

Description

• Fixed implicit cast to std::string in VS2019. Implicit cast to std::string broken again with VS2019 16.5.0 #2006 PR for #2006 to test in AppVeyor. #2008 Compiler Errors under VS2019 in Appveyor CI #2009

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