Conf macro improvements

[camsteffen]

changelog: Allow default_trait_access in macros

Mainly this is a change to use serde as in Manually implementing Deserialize for a struct, which opens the door for a cleaner implementation overall.

• Allow default_trait_access in macros (tangential, but used in this PR)
• Deserialize into TryConf { conf, errors } instead of using a global ERRORS variable.
• Improve the define_Conf! macro
  • Remove the redundant string literal (name, "name", ..)
  • Support deprecated configs with #[conf_deprecated(message)]. Message shows in error.
  • Make the default value optional. Use Default::default() if omitted.
• Invalid config value error now shows the key (see test output)
• Cleaner impl Default for Conf (no toml::from_str(""))

[rust-highfive]

r? @llogiq

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[llogiq]

Thank you, that is a solid improvement!

@bors r+

[bors]

📌 Commit 1e22e56 has been approved by llogiq

[bors]

⌛ Testing commit 1e22e56 with merge 019dfb9...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: llogiq
Pushing 019dfb9 to master...

[flip1995]

This broke the documentation generation script. The script works with regexes. I assume the change from , to = is the problem here. See commit 0ae8be3

Also cc @xFrednet making you aware that the conf macro changed a bit, since I think you already have started / finished work on this for the metadata collection monster.

[xFrednet]

Yup, my implementation will be slightly effected by this change, but still very manageable. The ping was definitely good! <3

@camsteffen Could you also adapt the documentation with the new configuration syntax. I think the only effected area should be this: Adding configuration to a lint

[camsteffen]

Whoops. Yes I can fix those two things.

[flip1995]

@camsteffen When working on the documentation, I recommend using cargo dev serve which live-updates the documentation page in your browser when change something.