cli(ux): rename 'node env' → 'NODE_ENV' and show selected --env profile in describe command

[bulgarian-beast]

Q	A
Bug fix?	no (UX clarification)
New feature?	yes (display selected --env profile)
BC breaks?	no
Deprecations?	no
Tests pass?	yes (manual; CI pending)
Fixed tickets	N/A
License	MIT
Doc PR	N/A

Changes

• Rename the misleading label node env → NODE_ENV in pm2 describe.
• Add a new row in pm2 describe: PM2 --env, which shows the ecosystem profile selected with --env <name> (e.g., test, production).
• Persist the selected profile name during env merge as pm2_env_name so the UX layer can display it.

Why

Users often confuse the old “node env” label with PM2’s ecosystem profile. This PR:

• Makes it explicit that the field is the process NODE_ENV.
• Surfaces the active PM2 environment profile chosen via --env, which previously wasn’t visible anywhere in describe.

Output:

# pm2 describe demo

┌───────────────────┬────────────────────────────────────────┐
│ status            │ online                                 │
│ name              │ demo                                   │
│ namespace         │ default                                │
│ version           │ N/A                                    │
│ restarts          │ 4                                      │
│ uptime            │ 7s                                     │
│ script path       │ /private/tmp/pm2-test/app.js           │
│ script args       │ N/A                                    │
│ error log path    │ /Users/sofian/.pm2/logs/demo-error.log │
│ out log path      │ /Users/sofian/.pm2/logs/demo-out.log   │
│ pid path          │ /Users/sofian/.pm2/pids/demo-0.pid     │
│ interpreter       │ node                                   │
│ interpreter args  │ N/A                                    │
│ script id         │ 0                                      │
│ exec cwd          │ /private/tmp/pm2-test                  │
│ exec mode         │ fork_mode                              │
│ node.js version   │ 24.4.1                                 │
│ NODE_ENV          │ production                             │
│ PM2 --env         │ test                                   │
│ watch & reload    │ ✘                                      │
│ unstable restarts │ 0                                      │
│ created at        │ 2025-08-11T11:46:08.234Z               │
└───────────────────┴────────────────────────────────────────┘

How

• lib/Common.js
  When merging environment variables, persist the selected profile name on the process config:

  • Set pm2_env_name = <env_name> (or 'default' when unset).

• lib/API/UX/pm2-describe.js

  • Rename label to NODE_ENV (guarded: shows N/A if unset).
  • Add new row PM2 --env using pm2_env_name (fallback to 'default').

Behavior / Compatibility

• Output-only change (no runtime/process behavior impacted).
• If no --env is provided, PM2 --env shows default.
• If NODE_ENV isn’t set, it shows N/A instead of undefined.
• No JSON schema or programmatic API changes.

Before / After (example)

Before

│ node env          │ N/A │

After

│ NODE_ENV   │ production │
│ PM2 --env  │ test       │

Test plan (manual)

# Link locally (for manual E2E verification)
npm install
npm link

# Minimal repro
mkdir -p /tmp/pm2-ecosystem-test && cd /tmp/pm2-ecosystem-test
printf 'setInterval(() => {}, 1000)\n' > app.js
cat > ecosystem.config.js <<'EOF'
module.exports = {
  apps: [{
    name: 'demo',
    script: 'app.js',
    env:      { NODE_ENV: 'development' },
    env_test: { NODE_ENV: 'production'  }
  }]
};
EOF

# Start with a named ecosystem env
pm2 start ecosystem.config.js --env test -f

# Verify describe output
pm2 describe demo


┌───────────────────┬────────────────────────────────────────┐
│ status            │ online                                 │
│ name              │ demo                                   │
│ namespace         │ default                                │
│ version           │ N/A                                    │
│ restarts          │ 4                                      │
│ uptime            │ 7s                                     │
│ script path       │ /private/tmp/pm2-test/app.js           │
│ script args       │ N/A                                    │
│ error log path    │ /Users/sofian/.pm2/logs/demo-error.log │
│ out log path      │ /Users/sofian/.pm2/logs/demo-out.log   │
│ pid path          │ /Users/sofian/.pm2/pids/demo-0.pid     │
│ interpreter       │ node                                   │
│ interpreter args  │ N/A                                    │
│ script id         │ 0                                      │
│ exec cwd          │ /private/tmp/pm2-test                  │
│ exec mode         │ fork_mode                              │
│ node.js version   │ 24.4.1                                 │
│ NODE_ENV          │ production                             │
│ PM2 --env         │ test                                   │
│ watch & reload    │ ✘                                      │
│ unstable restarts │ 0                                      │
│ created at        │ 2025-08-11T11:46:08.234Z               │
└───────────────────┴────────────────────────────────────────┘

Notes for reviewers

• Small, focused diff (two files).
• Clear UX win with minimal risk.
• Happy to adjust copy/labels if you prefer different wording.

[CLAassistant]

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