feat(tvix/cli): add toplevel progress span

This gives some better feedback something is going on, gives a (named)
root for all the progress children we're drawing, and also counts the
time we are in eval.

Change-Id: Ibe81dcebf0a2b59bb0680da62e206eb5270f9d3c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11798
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: aspen <root@gws.fyi>

tvix/Cargo.lock

@@ -4203,6 +4203,7 @@ dependencies = [
  "tikv-jemallocator",
  "tokio",
  "tracing",
+ "tracing-indicatif",
  "tvix-build",
  "tvix-castore",
  "tvix-eval",

tvix/Cargo.nix

@@ -13305,6 +13305,10 @@ rec {
             name = "tracing";
             packageId = "tracing";
           }
+          {
+            name = "tracing-indicatif";
+            packageId = "tracing-indicatif";
+          }
           {
             name = "tvix-build";
             packageId = "tvix-build";

tvix/cli/Cargo.toml

@@ -23,6 +23,7 @@ rnix = "0.11.0"
 thiserror = "1.0.38"
 tokio = "1.28.0"
 tracing = "0.1.40"
+tracing-indicatif = "0.3.6"
 
 [dependencies.wu-manber]
 git = "https://github.com/tvlfyi/wu-manber.git"

tvix/cli/src/main.rs

@@ -4,7 +4,8 @@ use clap::Parser;
 use repl::Repl;
 use std::rc::Rc;
 use std::{fs, path::PathBuf};
-use tracing::Level;
+use tracing::{instrument, Level, Span};
+use tracing_indicatif::span_ext::IndicatifSpanExt;
 use tvix_build::buildservice;
 use tvix_eval::builtins::impure_builtins;
 use tvix_eval::observer::{DisassemblingObserver, TracingObserver};
@@ -152,6 +153,7 @@ struct IncompleteInput;
 /// Interprets the given code snippet, printing out warnings, errors
 /// and the result itself. The return value indicates whether
 /// evaluation succeeded.
+#[instrument(skip_all, fields(indicatif.pb_show=1))]
 fn interpret(
     tvix_store_io: Rc<TvixStoreIO>,
     code: &str,
@@ -160,6 +162,11 @@ fn interpret(
     explain: bool,
     allow_incomplete: AllowIncomplete,
 ) -> Result<bool, IncompleteInput> {
+    let span = Span::current();
+    span.pb_start();
+    span.pb_set_style(&tvix_tracing::PB_SPINNER_STYLE);
+    span.pb_set_message("Setting up evaluator…");
+
     let mut eval = tvix_eval::Evaluation::new(
         Box::new(TvixIO::new(tvix_store_io.clone() as Rc<dyn EvalIO>)) as Box<dyn EvalIO>,
         true,
@@ -187,6 +194,7 @@ fn interpret(
             eval.runtime_observer = Some(&mut runtime_observer);
         }
 
+        span.pb_set_message("Evaluating…");
         eval.evaluate(code, path)
     };