feat(rustdoc): diplay env vars in extra verbose mode

This seems to be an overlook

Author: weihanglo

src/cargo/core/compiler/compilation.rs

@@ -199,7 +199,10 @@ impl<'gctx> Compilation<'gctx> {
         unit: &Unit,
         script_meta: Option<Metadata>,
     ) -> CargoResult<ProcessBuilder> {
-        let rustdoc = ProcessBuilder::new(&*self.gctx.rustdoc()?);
+        let mut rustdoc = ProcessBuilder::new(&*self.gctx.rustdoc()?);
+        if self.gctx.extra_verbose() {
+            rustdoc.display_env_vars();
+        }
         let cmd = fill_rustc_tool_env(rustdoc, unit);
         let mut cmd = self.fill_env(cmd, &unit.pkg, script_meta, unit.kind, ToolKind::Rustdoc)?;
         cmd.retry_with_argfile(true);

tests/testsuite/profile_targets.rs

@@ -724,7 +724,7 @@ fn profile_selection_doc() {
 [RUNNING] `[..][ROOT]/foo/target/debug/build/foo-[HASH]/build-script-build`
 [foo 0.0.1] foo custom build PROFILE=debug DEBUG=true OPT_LEVEL=0
 [DOCUMENTING] foo v0.0.1 ([ROOT]/foo)
-[RUNNING] `rustdoc [..]--crate-name foo src/lib.rs [..]
+[RUNNING] `[..] rustdoc [..]--crate-name foo src/lib.rs [..]
 [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
 [GENERATED] [ROOT]/foo/target/doc/foo/index.html