cmd: Fix "PATH=value" command.

programs/cmd/builtins.c

@@ -2371,7 +2371,7 @@ void WCMD_setshow_path (const WCHAR *command) {
   static const WCHAR pathW[] = {'P','A','T','H','\0'};
   static const WCHAR pathEqW[] = {'P','A','T','H','=','\0'};
 
-  if (strlenW(param1) == 0) {
+  if (strlenW(param1) == 0 && strlenW(param2) == 0) {
     status = GetEnvironmentVariableW(pathW, string, sizeof(string)/sizeof(WCHAR));
     if (status != 0) {
       WCMD_output_asis ( pathEqW);

programs/cmd/tests/test_builtins.cmd

@@ -1530,6 +1530,17 @@ if d==d goto dest4
 :dest4@space@
 echo goto with a following space worked
 
+echo ------------ Testing PATH ------------
+set backup_path=%path%
+set path=original
+path
+path try2
+path
+path=try3
+path
+set path=%backup_path%
+set backup_path=
+
 echo ------------ Testing combined CALLs/GOTOs ------------
 echo @echo off>foo.cmd
 echo goto :eof>>foot.cmd

programs/cmd/tests/test_builtins.cmd.exp

@@ -825,6 +825,10 @@ goto with no leading space worked
 goto with a leading space worked
 goto with a leading tab worked
 goto with a following space worked
+------------ Testing PATH ------------
+PATH=original
+PATH=try2
+PATH=try3
 ------------ Testing combined CALLs/GOTOs ------------
 world
 cheball