Improve crate_universe debug logging for cargo tree parsing (#2854)

It's much easier to understand what's going on if I can see a standard
`cargo tree` output.

crate_universe/src/cli.rs

@@ -86,7 +86,7 @@ impl LoggingFormatEvent {
 }
 
 /// Initialize logging for one of the cli options.
-pub fn init_logging(name: &str) {
+pub fn init_logging(name: &str, verbose: bool) {
     if !EXPECTED_LOGGER_NAMES.contains(&name) {
         panic!(
             "Unexpected logger name {}, use of one of {:?}",
@@ -98,11 +98,7 @@ pub fn init_logging(name: &str) {
     let subscriber = FmtSubscriber::builder()
         // all spans/events with a level higher than TRACE (e.g, debug, info, warn, etc.)
         // will be written to stdout.
-        .with_max_level(
-            std::env::var("CARGO_BAZEL_DEBUG")
-                .map(|_| Level::DEBUG)
-                .unwrap_or(Level::INFO),
-        )
+        .with_max_level(if verbose { Level::DEBUG } else { Level::INFO })
         .event_format(LoggingFormatEvent::new(name))
         // completes the builder.
         .finish();

crate_universe/src/main.rs

@@ -6,21 +6,23 @@ fn main() -> cli::Result<()> {
     // Parse arguments
     let opt = cli::parse_args();
 
+    let verbose_logging = std::env::var("CARGO_BAZEL_DEBUG").is_ok();
+
     match opt {
         cli::Options::Generate(opt) => {
-            cli::init_logging("Generate");
+            cli::init_logging("Generate", verbose_logging);
             cli::generate(opt)
         }
         cli::Options::Splice(opt) => {
-            cli::init_logging("Splice");
+            cli::init_logging("Splice", verbose_logging);
             cli::splice(opt)
         }
         cli::Options::Query(opt) => {
-            cli::init_logging("Query");
+            cli::init_logging("Query", verbose_logging);
             cli::query(opt)
         }
         cli::Options::Vendor(opt) => {
-            cli::init_logging("Vendor");
+            cli::init_logging("Vendor", verbose_logging);
             cli::vendor(opt)
         }
     }

crate_universe/src/metadata/dependency.rs

@@ -517,7 +517,7 @@ mod test {
                 let pkg = &metadata[&node.id];
                 pkg.name == name
             })
-            .unwrap()
+            .unwrap_or_else(|| panic!("Unable to find node '{}'", name))
     }
 
     #[test]

crate_universe/test_data/metadata/nested_build_dependencies/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "nested_build_dependencies"
+version = "0.0.0"
+edition = "2021"
+
+# Required to satisfy cargo but no `lib.rs` is expected to
+# exist within test data.
+[lib]
+path = "lib.rs"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[build-dependencies]
+num-traits = "0.2.19"
+syn = "2.0.77"
+
+[dev-dependencies]
+proc-macro-error-attr = "=1.0.4"