Test unused_crate_dependencies in CI

To make sure we don't have any unnecessary dependencies in Cargo.toml,
this commit adds a command line that checks with the
unused_crate_dependencies lint.

This commit also adds command lines that build with all combinations of
features to catch possible build errors that do not happen with the
check command.

Some test commands are removed from check-extra.sh because they are
already run in check.sh.

.github/workflows/rust.yml

@@ -19,8 +19,6 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: Swatinem/rust-cache@v2
-    - name: Build
-      run: cargo build
     - name: Run basic tests
       run: ./check.sh -v
   clippy:

check-extra.sh

@@ -4,8 +4,6 @@ if [ "$*" = "" ]; then quiet='--quiet'; else quiet=''; fi
 
 set -x
 
-cargo check
-
 cargo tomlfmt --dryrun --path Cargo.toml
 cargo tomlfmt --dryrun --path yash/Cargo.toml
 cargo tomlfmt --dryrun --path yash-arith/Cargo.toml
@@ -16,12 +14,29 @@ cargo tomlfmt --dryrun --path yash-quote/Cargo.toml
 cargo tomlfmt --dryrun --path yash-semantics/Cargo.toml
 cargo tomlfmt --dryrun --path yash-syntax/Cargo.toml
 
-cargo test --package 'yash-arith' -- $quiet
-cargo test --package 'yash-builtin' -- $quiet
+# Make sure we don't have any unnecessary dependencies in Cargo.toml.
+RUSTFLAGS='-D unused_crate_dependencies' cargo check --lib --all-features
+
+# Make sure the crates can be built with all combinations of features.
+cargo build --package 'yash' --all-targets
+cargo build --package 'yash-arith' --all-targets
+cargo build --package 'yash-builtin' --all-targets
+cargo build --package 'yash-builtin' --all-targets --no-default-features
+cargo build --package 'yash-env' --all-targets
+cargo build --package 'yash-fnmatch' --all-targets
+cargo build --package 'yash-quote' --all-targets
+cargo build --package 'yash-semantics' --all-targets
+cargo build --package 'yash-syntax' --all-targets
+cargo build --package 'yash-syntax' --all-targets --features annotate-snippets
+
+# Test with non-default feature configurations.
+#cargo test --package 'yash' -- $quiet
+#cargo test --package 'yash-arith' -- $quiet
+#cargo test --package 'yash-builtin' -- $quiet
 cargo test --package 'yash-builtin' --no-default-features -- $quiet
-cargo test --package 'yash-env' -- $quiet
-cargo test --package 'yash-fnmatch' -- $quiet
-cargo test --package 'yash-quote' -- $quiet
-cargo test --package 'yash-semantics' -- $quiet
-cargo test --package 'yash-syntax' -- $quiet
+#cargo test --package 'yash-env' -- $quiet
+#cargo test --package 'yash-fnmatch' -- $quiet
+#cargo test --package 'yash-quote' -- $quiet
+#cargo test --package 'yash-semantics' -- $quiet
+#cargo test --package 'yash-syntax' -- $quiet
 cargo test --package 'yash-syntax' --features annotate-snippets -- $quiet