Add signal() test

lib/libexec.sh

@@ -119,15 +119,17 @@ sleep_wait() {
   esac
 }
 
-
-if $SHELLSPEC_KILL -0 $$ 2>/dev/null; then
-  signal() {
-    "$SHELLSPEC_KILL" "$1" "$2"
-  }
-else
-  signal() {
-    "$SHELLSPEC_KILL" -s "${1#-}" "$2"
-  }
-fi
+signal() {
+  if $SHELLSPEC_KILL -0 $$ 2>/dev/null; then
+    signal() {
+      "$SHELLSPEC_KILL" "$1" "$2"
+    }
+  else
+    signal() {
+      "$SHELLSPEC_KILL" -s "${1#-}" "$2"
+    }
+  fi
+  signal "$@"
+}
 
 use puts putsn

spec/libexec_spec.sh

@@ -84,4 +84,21 @@ Describe 'libexec.sh'
       The lines of stdout should eq 2
     End
   End
+
+  Describe "signal()"
+    posix_kill() { eval SHELLSPEC_KILL=echo && true; }
+    non_posix_kill() { eval SHELLSPEC_KILL=echo && false; }
+
+    It "calls kill (posix)"
+      BeforeCall SHELLSPEC_KILL=posix_kill
+      When call signal -TERM 0
+      The stdout should eq "-TERM 0"
+    End
+
+    It "calls kill (non-posix)"
+      BeforeCall SHELLSPEC_KILL=non_posix_kill
+      When call signal -TERM 0
+      The stdout should eq "-s TERM 0"
+    End
+  End
 End