Error message when creating a bin project suggests [bin] section in Cargo.toml instead of [[bin]]

[geauxvirtual]

Problem

When attempting to create project with an invalid name, such as with a leading number instead of a letter, cargo outputs an error with a suggestion to set the name for the binary via a [bin] section being added to Cargo.toml. However, adding a [bin] section to Cargo.toml causes another error to be thrown when trying to compile the project invalid type: map, expected a sequence for key "bin" as the key should be [[bin]] in Cargo.toml.

Steps

1. Run cargo init --bin 1foo
2. Error message suggests adding [bin] section.
3. Add [bin] section and try to compile project results in another error message

Possible Solution(s)

Help message should provide the proper key to be added to Cargo.toml.
[[bin]]

Notes

Output of cargo version: cargo 1.51.0 (43b129a 2021-03-16)

Checking the project, this is still the case in current master branch.

[dswij]

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