Add cross-dev binary with target info utilities.

Add `target-info` subcommands. This provides the target info for the
provided targets, or all targets if none are provided.

```bash
cross-dev target-info
cross-dev target-info arm-unknown-linux-gnueabihf
```

`target-info` also accepts the following flags:
- `-v`, `--verbose`: print verbose diagnostic output.
- `--engine`: specify the container engine to use.
- `--registry`: the registry for the image.
- `--repository`: the repository for the image.
- `--tag`: the tag for the image.

Other changes:
- Updated the CI to test building `cross-dev`.
- Add target info support for Dragonfly.

.github/workflows/ci.yml

@@ -249,6 +249,9 @@ jobs:
         if: matrix.deploy
         run: cargo install --path . --force
 
+      - name: Build cross-dev
+        run: cargo build --features=dev
+
       - uses: ./.github/actions/cargo-install-upload-artifacts
         if: matrix.deploy
         with:

CHANGELOG.md

@@ -7,6 +7,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+- #767 - added the `cross-util` and `cross-dev` commands.
 - #741 - added `armv7-unknown-linux-gnueabi` and `armv7-unknown-linux-musleabi` targets.
 - #721 - add support for running doctests on nightly if `CROSS_UNSTABLE_ENABLE_DOCTESTS=true`.
 - #719 - add `--list` to known subcommands.

Cargo.toml

@@ -9,8 +9,13 @@ repository = "https://github.com/cross-rs/cross"
 version = "0.2.1"
 edition = "2021"
 
+[features]
+default = []
+dev = ["serde_yaml"]
+
 [dependencies]
 atty = "0.2"
+clap = { version = "3.1.18", features = ["derive"] }
 color-eyre = "0.6"
 eyre = "0.6"
 home = "0.5"
@@ -20,6 +25,7 @@ which = { version = "4", default_features = false }
 shell-escape = "0.1"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
+serde_yaml = { version = "0.8", optional = true }
 serde_ignored = "0.1.2"
 
 [target.'cfg(not(windows))'.dependencies]
@@ -37,3 +43,8 @@ lto = true
 regex = "1"
 once_cell = "1"
 walkdir = "2"
+
+[[bin]]
+name = "cross-dev"
+path = "cross-dev/main.rs"
+required-features = ["dev"]