What it does

Lints the Cargo.toml manifest file and make sure everything is alright.

Lints

• Cargo.toml — file is missing.
• Cargo.toml — file is misnamed, maybe "cargo.toml or "CARGO.toml", etc
• package.name — contains characters not allowed
• package.version — does not follow semantic versioning
• package.authors — at least one author required
• package.edition — is unknown
• package.documentation — is http not https
• package.readme — file no found
• package.homepage — is http not https
• package.repository — is http not https
• package.license — is not a SPDX 2.1 license expression
• package.license-file — file not found
• package.keywords — contains invalid letters
• package.keywords — exceeds 5 keywords
• package.categories — exceed 5 categories
• package.categories — the category does not exist
• package.build — file not found
• package.foo — unknown field
• features — feature name starts with "use-", "using-" or "with-"
• chapters are in the wrong order
• fields are in the wrong order
• dependencies are not sorted alphabetically

https://doc.rust-lang.org/cargo/reference/manifest.html