updated for version 7.3.445

Problem:    Can't properly escape commands for cmd.exe.
Solution:   Default 'shellxquote' to '('.  Append ')' to make '(command)'.
            No need to use "/s" for 'shellcmdflag'.

src/misc2.c

@@ -3230,7 +3230,11 @@ call_shell(cmd, opt)
 	    {
 		STRCPY(ncmd, p_sxq);
 		STRCAT(ncmd, cmd);
-		STRCAT(ncmd, p_sxq);
+		/* When 'shellxquote' is ( append ).
+		 * When 'shellxquote' is "( append )". */
+		STRCAT(ncmd, STRCMP(p_sxq, "(") == 0 ? (char_u *)")"
+			   : STRCMP(p_sxq, "\"(") == 0 ? (char_u *)")\""
+			   : p_sxq);
 		retval = mch_call_shell(ncmd, opt);
 		vim_free(ncmd);
 	    }

src/option.c

@@ -3933,27 +3933,22 @@ set_init_3()
 	 *   my path/to/echo" "my args to echo
 	 * when executed.
 	 *
-	 * To avoid this, use the /s argument in addition to /c to force the
-	 * stripping behavior, and also set shellxquote to automatically
-	 * surround the entire command in quotes (which get stripped as
-	 * noted).
+	 * To avoid this, set shellxquote to surround the command in
+	 * parenthesis.  This appears to make most commands work, without
+	 * breaking commands that worked previously, such as
+	 * '"path with spaces/cmd" "a&b"'.
 	 */
-
-	/* Set shellxquote default to add the quotes to be stripped. */
 	idx3 = findoption((char_u *)"sxq");
 	if (idx3 >= 0 && !(options[idx3].flags & P_WAS_SET))
 	{
-	    p_sxq = (char_u *)"\"";
+	    p_sxq = (char_u *)"(";
 	    options[idx3].def_val[VI_DEFAULT] = p_sxq;
 	}
 
-	/* Set shellcmdflag default to always strip the quotes, note the order
-	 * between /s and /c is important or cmd.exe will treat the /s as part
-	 * of the command to be executed.  */
 	idx3 = findoption((char_u *)"shcf");
 	if (idx3 >= 0 && !(options[idx3].flags & P_WAS_SET))
 	{
-	    p_shcf = (char_u *)"/s /c";
+	    p_shcf = (char_u *)"/c";
 	    options[idx3].def_val[VI_DEFAULT] = p_shcf;
 	}
     }

src/os_win32.c

@@ -3908,8 +3908,13 @@ mch_call_shell(
 	newcmd = lalloc(cmdlen, TRUE);
 	if (newcmd != NULL)
 	{
-	    char_u *cmdbase = (*cmd == '"' ? cmd + 1 : cmd);
+	    char_u *cmdbase = cmd;
 
+	    /* Skip a leading ", ( and "(. */
+	    if (*cmdbase == '"' )
+		++cmdbase;
+	    if (*cmdbase == '(')
+		++cmdbase;
 	    if ((STRNICMP(cmdbase, "start", 5) == 0) && vim_iswhite(cmdbase[5]))
 	    {
 		STARTUPINFO		si;
@@ -3953,16 +3958,26 @@ mch_call_shell(
 		 * empty, keep the double quotes around the command.
 		 * Otherwise remove the double quotes, they aren't needed
 		 * here, because we don't use a shell to run the command. */
-		if (*cmd == '"' && *p_sxq == NUL)
+		if (cmdbase > cmd)
 		{
-		    newcmd[0] = '"';
-		    STRCPY(newcmd + 1, cmdbase);
-		}
-		else
-		{
-		    STRCPY(newcmd, cmdbase);
-		    if (*cmd == '"' && *newcmd != NUL)
-			newcmd[STRLEN(newcmd) - 1] = NUL;
+		    if (STRNCMP(cmd, p_sxq, cmd - cmdbase) != 0)
+		    {
+			STRCPY(newcmd, cmd);
+		    }
+		    else
+		    {
+			char_u *p;
+
+			STRCPY(newcmd, cmdbase);
+			/* Remove a trailing ", ) and )" if they have a match
+			 * at the start of the command. */
+			p = newcmd + STRLEN(newcmd);
+			if (p > newcmd && p[-1] == '"' && *cmd == '"')
+			    *--p = NUL;
+			if (p > newcmd && p[-1] == ')'
+					     && (*cmd =='(' || cmd[1] == '('))
+			    *--p = NUL;
+		    }
 		}
 
 		/*
@@ -3970,7 +3985,7 @@ mch_call_shell(
 		 * inherit our handles which causes unpleasant dangling swap
 		 * files if we exit before the spawned process
 		 */
-		if (CreateProcess (NULL,	// Executable name
+		if (CreateProcess(NULL,		// Executable name
 			newcmd,			// Command to execute
 			NULL,			// Process security attributes
 			NULL,			// Thread security attributes

src/version.c

@@ -714,6 +714,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    445,
 /**/
     444,
 /**/