lib: allow process kill by signal number

This brings the behaviour in line with the documentation. PR-URL: #16944 Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: sam-github

lib/internal/process.js

@@ -158,8 +158,8 @@ function setupKillAndExit(){
 }
 
 // preserve null signal
-if(0===sig){
-err=process._kill(pid,0);
+if(sig===(sig|0)){
+err=process._kill(pid,sig);
 }else{
 sig=sig||'SIGTERM';
 if(constants[sig]){

test/parallel/test-process-kill-pid.js

@@ -57,16 +57,19 @@ assert.throws(function(){process.kill(1 / 0)},
 assert.throws(function(){process.kill(-1/0);},
 invalidPidArgument);
 
-// Test that kill throws an error for invalid signal
-constunknownSignal=common.expectsError({
+// Test that kill throws an error for unknown signal names
+common.expectsError(()=>process.kill(0,'test'),{
 code: 'ERR_UNKNOWN_SIGNAL',
 type: TypeError,
 message: 'Unknown signal: test'
 });
 
-
-assert.throws(function(){process.kill(1,'test');},
-unknownSignal);
+// Test that kill throws an error for invalid signal numbers
+common.expectsError(()=>process.kill(0,987),{
+code: 'EINVAL',
+type: Error,
+message: 'kill EINVAL'
+});
 
 // Test kill argument processing in valid cases.
 //
@@ -99,6 +102,11 @@ kill(0, undefined, 0, 15);
 kill('0','SIGHUP',0,1);
 kill('0',undefined,0,15);
 
+// Confirm that numeric signal arguments are supported
+
+kill(0,1,0,1);
+kill(0,15,0,15);
+
 // negative numbers are meaningful on unix
 kill(-1,'SIGHUP',-1,1);
 kill(-1,undefined,-1,15);