A cargo subcommand for displaying when different versions of a same dependency are pulled in.
Once installed, running cargo duplicates in a project directory looks like the following:
```text $ cargo duplicates Package Versions ------- -------- cfg-if 1.0.0 0.1.10 hex 0.4.2 0.3.2 humantime 2.0.1 1.3.0
cfg-if 1.0.0: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => flate2 1.0.19 => crc32fast 1.2.1 => cfg-if 1.0.0 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => filetime 0.2.13 => cfg-if 1.0.0 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tar 0.4.30 => filetime 0.2.13 => cfg-if 1.0.0 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => flate2 1.0.19 => cfg-if 1.0.0 cfg-if 0.1.10: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => crossbeam-utils 0.7.2 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => ignore 0.4.16 => crossbeam-utils 0.7.2 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tempfile 3.1.0 => rand 0.7.3 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => im-rc 15.0.0 => randcore 0.5.1 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tempfile 3.1.0 => rand 0.7.3 => randcore 0.5.1 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tempfile 3.1.0 => rand 0.7.3 => randchacha 0.2.2 => randcore 0.5.1 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tempfile 3.1.0 => rand 0.7.3 => randhc 0.2.0 => randcore 0.5.1 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => im-rc 15.0.0 => randxoshiro 0.4.0 => randcore 0.5.1 => getrandom 0.1.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => env_logger 0.7.1 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => git2 0.13.12 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => git2-curl 0.14.1 => git2 0.13.12 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => git2-curl 0.14.1 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => ignore 0.4.16 => globset 0.4.6 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => ignore 0.4.16 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => rustfix 0.5.1 => log 0.4.11 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => crypto-hash 0.3.4 => openssl 0.10.30 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => curl 0.4.34 => socket2 0.3.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => crates-io 0.31.1 => curl 0.4.34 => socket2 0.3.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => git2-curl 0.14.1 => curl 0.4.34 => socket2 0.3.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => miow 0.3.5 => socket2 0.3.15 => cfg-if 0.1.10 - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => tempfile 3.1.0 => cfg-if 0.1.10
hex 0.4.2: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => hex 0.4.2 hex 0.3.2: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => crypto-hash 0.3.4 => hex 0.3.2
humantime 2.0.1: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => humantime 2.0.1 humantime 1.3.0: - Because of cargo-duplicates 0.2.1 => cargo 0.48.0 => env_logger 0.7.1 => humantime 1.3.0 ```