cleanup and update test case for job info format

src/job.cpp

@@ -335,17 +335,9 @@ std::string JobObject::formatInfo(JobInfoFormat fmt) const {
       if (i > 0) {
         value.append(prefixLen, ' ');
       }
-      value += ' ';
-      auto &pid = fragments[i].first;
-      value += pid;
-      value.append(pidLen - pid.size(), ' ');
-      value += ' ';
-      auto &state = fragments[i].second;
-      value += state;
-      value.append(stateLen - state.size(), ' ');
-      value += "  ";
-      value += descs[i];
-      value += '\n';
+      auto &[pid, state] = fragments[i];
+      formatTo(value, " %-*s %-*s  %s\n", static_cast<int>(pidLen), pid.c_str(),
+               static_cast<int>(stateLen), state.c_str(), descs[i].c_str());
     }
   }
   return value;

test/exec/cases/base/builtin_jobs.ds

@@ -83,6 +83,16 @@ $out = IFS=$'\n' $(jobs -l $j)
 assert $out.size() == 1
 assert $out[0] == "[1] - ${$j.pid(0)!} Stopped  {\n    while(true 1) {}\n}"
 
+# -l option (pipeline)
+var j3 = while(true) {} | true &
+defer { $j3.raise($SIGKILL); }
+sleep 0.5
+$j3.poll()
+$out = IFS=$'\n' $(jobs -l $j3)
+assert $out.size() == 2
+assert $out[0] =~ $/^\[3\] \+ +[0-9]+ +Running  while\(true\) {} \|$/ : ">> ${$out[0]}"
+assert $out[1] =~ $/^ +[0-9]+ +Done  +true$/ : ">> ${$out[1]}"
+
 # help
 assert help jobs | grep '^jobs: jobs \[-lprs] \[jobspec ...]'
 assert $PIPESTATUS[0] == 0 && $PIPESTATUS[1] == 0