QuickRust documentation

How to see the warnings, errors and full log of a build

This guide shows you how to read everything a build printed, after QuickRust has summed it up in a terminal.

In this section

In a terminal, QuickRust shows every error in full as it arrives, but only counts warnings:

OK   Built: 1 compiled [100ms]
WARN 2 warnings in demo (bin): dead_code x1, unused_variables x1; `qrust warnings` shows them

Nothing is lost: the whole output of every build QuickRust rendered is stored with its run.

Show the warnings

qrust warnings

prints every warning of the latest build as rustc wrote it. To narrow it down:

qrust warnings --crate demo
qrust warnings --lint dead_code
qrust warnings --crate demo --lint unused_variables

If nothing matches, it says so (No warnings in run <id> matching the filter.).

Show the errors again

qrust errors
qrust errors --crate demo

This is useful when the errors have scrolled away, or to pipe them somewhere:

qrust errors | less -R

Show everything, in order

qrust log            # Cargo's lines and rustc's messages, as a plain build would have printed them
qrust log --raw      # the stored stream as Cargo emitted it, including its JSON messages

Look at an earlier build

Every one of these commands takes --run:

qrust warnings --run latest~1        # the build before the latest
qrust log --run 01M4SFQZ             # a run id, or a unique prefix or suffix of one

qrust runs lists the recorded runs of the workspace with their ids.

Get Cargo’s own output instead

If you want Cargo to print a build itself, line by line:

  • for one command, pass -v (also -q, --message-format, or --color): QuickRust leaves Cargo’s output untouched;
  • for one shell, export QRUST_OUTPUT=cargo;
  • for good, output = "cargo" in ~/.qrust/config.toml or the project’s .qrust/config.toml.

Output written to a pipe or a file is always Cargo’s own, so cargo build 2>&1 | tee build.log and CI logs need nothing.

If the output was not stored

FAIL this run's output was not stored: it was not rendered by QuickRust (not a terminal, or output = "cargo"), or its raw events were pruned

Output is stored only for builds QuickRust rendered in a terminal, and only for the most recent runs (measurement.keep-raw-events, 20 by default). A build whose output went to a pipe, ran with -v, or ran with output = "cargo" printed Cargo’s output directly. Run the build again in a terminal, or read the log you captured.