transcript is a CLI tool for snapshot testing command-line programs.

Tests are written in a small, line-oriented format (usually *.cmdt) that captures a shell session: commands, stdout/stderr, and exit codes. The format is designed to be readable in reviews and easy to update when outputs change.

• Record sessions interactively (transcript shell)
• Check transcripts in CI (transcript check)
• Update expectations when outputs change (transcript update)
• Reference external files for large or binary output (1< / 2<)
• Embed transcripts in Go tests via cmdtest.Check

Create a transcript and check it:

cat > demo.cmdt <<EOF
$ echo stdout
1 stdout

$ echo stderr 1>&2
2 stderr

# Non-zero exit codes.
$ false
? 1
EOF

transcript check ./demo.cmdt

go install github.com/deref/transcript@latest

Transcript is not Go-specific, but it is written in Go and can be used in Go test suites via cmdtest.Check.

• User guide
• File format reference
• Go test caching notes
• Editor support