lib: fix: propagate exit codes from spawned processes (#3)

The run-shared-scripts tool spawned child processes but never waited
for them to complete or captured their exit codes, causing all scripts
to appear successful even when they failed. This made it impossible for
CI systems and build pipelines to detect failures.

The run() function now returns a Promise that resolves with the child
process exit code, and the bin script awaits this result and sets
process.exitCode accordingly.

- Modified lib/index.js: wrap spawn in Promise, resolve with exit code
- Modified bin/rss.js: await run() and set process.exitCode
- Return 0 for successful execution and dry-run mode
- Return 1 when script name not found in rss configuration
- Added example test scripts to verify exit code propagation

Signed-off-by: Eric Wheeler <[email protected]>
Co-authored-by: Eric Wheeler <[email protected]>

Author: KJ7LNW

bin/rss.js

@@ -41,4 +41,5 @@ const cli = meow(
 
 const cmd = cli.input[0] || process.env.npm_lifecycle_event
 
-run(cmd, args, cli.flags)
+const exitCode = await run(cmd, args, cli.flags)
+process.exitCode = exitCode

example/package.json

@@ -19,6 +19,12 @@
     "test": {
       "file": "./scripts/test.js"
     },
+    "test-success": {
+      "file": "./scripts/test-success.js"
+    },
+    "test-failure": {
+      "file": "./scripts/test-failure.js"
+    },
     "pretest": "run-s -s clean:coverage",
     "start:1": "server --port {1}",
     "start:2": "server -a {1} --port {2}",

example/scripts/test-failure.js

@@ -0,0 +1,4 @@
+#!/usr/bin/env node
+
+console.log('test-failure: exiting with code 42')
+process.exit(42)

example/scripts/test-success.js

@@ -0,0 +1,4 @@
+#!/usr/bin/env node
+
+console.log('test-success: exiting with code 0')
+process.exit(0)

lib/index.js

@@ -131,13 +131,20 @@ export async function run(task, args, options) {
         ? fixFilePath(root, main)
         : await makeExecFile(root, task, main)
 
-      const child = spawn(exe, isFile ? args : [], { stdio: 'inherit' })
-
-      if (!isFile) {
-        child.on('exit', () => { fse.rm(exe) })
-      }
+      return new Promise((resolve) => {
+        const child = spawn(exe, isFile ? args : [], { stdio: 'inherit' })
+
+        child.on('exit', (code) => {
+          if (!isFile) {
+            fse.rm(exe)
+          }
+          resolve(code ?? 0)
+        })
+      })
     }
-  } else {
-    console.error(`unknown script: [${task}]`)
+    return 0
   }
+
+  console.error(`unknown script: [${task}]`)
+  return 1
 }