feat(cli): add --dry-run flag to generate sdl command

[lisa-assistant]

Background

There is a TODO comment in packages/cli/src/commands/generate/sdl/sdlHandler.js at line 243:

// TODO: Add --dry-run command
export const handler = async ({
  model,
  crud,
  force,
  tests,
  typescript,
  docs,
  rollback,
}) => {

What needs to be done

Add a --dry-run (or --dryRun) option to the generate sdl command. When passed, the command should:

1. Run through all the SDL and service file generation logic as normal
2. Print the files that would be created/modified (with their paths and optionally their contents)
3. Exit without writing anything to disk

This pattern already exists in the codebase — packages/cli/src/commands/upgrade/upgradeHandler.ts implements dryRun by passing the flag down and using skip: () => !!dryRun on tasks that write to disk.

Why

The SDL generator creates multiple files (SDL schema, service, tests). A --dry-run flag lets developers preview exactly what would be generated before committing, which is especially useful when exploring a new model or when they're unsure about the --crud flag.

Files to change

• packages/cli/src/commands/generate/sdl/sdl.js — add the yargs option definition (.option('dry-run', { type: 'boolean', default: false, description: 'Print files without writing them' }))
• packages/cli/src/commands/generate/sdl/sdlHandler.js — accept dryRun in the handler signature; pass it to writeFilesTask or skip that Listr task when dryRun is true

References

• packages/cli/src/commands/upgrade/upgradeHandler.ts — existing --dry-run implementation pattern
• packages/cli/src/lib/index.js writeFilesTask — the file-writing step to conditionally skip

[lisa-assistant]

Self-fix confidence: 8/10
The implementation pattern is already established in the upgrade command, and the scope is well-defined. The main uncertainty is whether writeFilesTask has a built-in dry-run hook or needs to be wrapped in a Listr skip condition, which requires a quick read of that helper.

[lisa-assistant]

Implementation Plan

Approach

Follow the pattern already established in upgradeHandler.ts: add the yargs option in the builder, accept dryRun in the handler, and use skip: () => !!dryRun on the file-writing Listr task. When dry-running, print the files that would be written instead of writing them.

---

Changes required

1. packages/cli/src/commands/generate/sdl/sdl.js — add the yargs option

In the builder function, after the existing .option('rollback', ...) block:

.option('dry-run', {
  description:
    'Print files that would be created/modified without writing to disk',
  type: 'boolean',
  default: false,
})

2. packages/cli/src/commands/generate/sdl/sdlHandler.js — accept and use dryRun

Change the handler signature:

export const handler = async ({
  model,
  crud,
  force,
  tests,
  typescript,
  docs,
  rollback,
  dryRun,   // <-- add
}) => {

Add to telemetry:

recordTelemetryAttributes({
  command: 'generate sdl',
  crud, force, tests, typescript, docs, rollback,
  dryRun,   // <-- add
})

Replace the SDL-writing task:

{
  title: 'Generating SDL files...',
  task: async (ctx, task) => {
    const f = await files({ name, tests, crud, typescript, docs })
    if (dryRun) {
      const { base } = getPaths()
      task.output = Object.keys(f)
        .map((filepath) => `  ${path.relative(base, filepath)}`)
        .join('\n')
      return
    }
    return writeFilesTask(f, { overwriteExisting: force })
  },
},

Skip the type-generation task during dry runs (no files were written):

{
  title: 'Generating types ...',
  skip: () => !!dryRun,
  task: async () => { /* existing */ },
},

Guard the rollback setup:

if (rollback && !force && !dryRun) {
  prepareForRollback(tasks)
}

Print a summary after tasks.run():

if (dryRun) {
  console.log(c.info('\nDry run complete. No files were written to disk.'))
}

---

Notes

• writeFilesTask has no built-in dry-run mode — skipping via early return in the task is the correct approach.
• task.output in Listr2 displays below the task title; using it to list the would-be files is consistent with how other tasks show progress.
• dryRun with --force is a no-op for the overwrite check but is harmless — nothing gets written either way.

Files to change

File	Change
packages/cli/src/commands/generate/sdl/sdl.js	Add --dry-run option to builder
packages/cli/src/commands/generate/sdl/sdlHandler.js	Accept dryRun, skip write task, skip type gen, print summary

[lisa-assistant]

Self-fix confidence: 8/10

The pattern is well-established (upgradeHandler.ts does it exactly this way), the scope is two files, and the Listr2 task skip API is straightforward. The 2-point deduction is for needing to verify that task.output renders correctly in the Listr2 version Cedar uses and that the getPaths import is already available in sdlHandler.js (it comes in transitively but may need an explicit import).

[github-actions]

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