Creating a reusable test-writing command
Reviewing auth.ts revealed that the session functions aren't tested yet—likely your next task. Since you'll be writing similar Vitest tests across the codebase, automate the workflow with a custom slash command. Save the common instructions in .claude/commands/write_tests.md using a $ARGUMENTS placeholder, then run /write_tests path/to/file.ts whenever you need tests for a file.
Note: Newer Claude Code versions pick up new commands automatically without a restart. The version used in this exercise environment still requires the /exit and restart shown here.
This exercise is part of the course
Claude Code in Action
Exercise instructions
- Start Claude Code with
claude. - Ask Claude to create a custom command at
.claude/commands/write_tests.mdthat uses$ARGUMENTSto write Vitest tests for the file the learner names. - Type
/exitto exit Claude Code.
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