Fix issue 241 (handle case where bash is not installed)

server/src/util/__tests__/sh.test.ts

@@ -1,6 +1,19 @@
 /* eslint-disable no-useless-escape */
 import * as sh from '../sh'
 
+describe('execShellScript', () => {
+  it('resolves if childprocess sends close signal', async () => {
+    return expect(sh.execShellScript('echo')).resolves
+  })
+
+  it('rejects if childprocess sends error signal', async () => {
+    // an error is sent if child_process cant spawn 'some-nonexistant-command'
+    return expect(
+      sh.execShellScript('something', 'some-nonexistant-command'),
+    ).rejects.toBe('Failed to execute something')
+  })
+})
+
 describe('getDocumentation', () => {
   it('returns null for an unknown builtin', async () => {
     const result = await sh.getShellDocumentation({ word: 'foobar' })

server/src/util/sh.ts

@@ -3,24 +3,27 @@ import * as ChildProcess from 'child_process'
 /**
  * Execute the following sh program.
  */
-export function execShellScript(body: string): Promise<string> {
+export function execShellScript(body: string, cmd = 'bash'): Promise<string> {
   const args = ['-c', body]
-  const process = ChildProcess.spawn('bash', args)
+  const process = ChildProcess.spawn(cmd, args)
 
   return new Promise((resolve, reject) => {
     let output = ''
 
-    process.stdout.on('data', buffer => {
-      output += buffer
-    })
-
-    process.on('close', returnCode => {
+    const handleClose = (returnCode: number | Error) => {
       if (returnCode === 0) {
         resolve(output)
       } else {
         reject(`Failed to execute ${body}`)
       }
+    }
+
+    process.stdout.on('data', buffer => {
+      output += buffer
     })
+
+    process.on('close', handleClose)
+    process.on('error', handleClose)
   })
 }