patch 8.0.1051: cannot run terminal with spaces in argument

Problem:    Cannot run terminal with spaces in argument.
Solution:   Accept backslash to escape space and other characters. (closes
            #1999)

src/os_unix.c

@@ -4094,8 +4094,17 @@ mch_parse_cmd(char_u *cmd, int use_shcf, char ***argv, int *argc)
 	    ++*argc;
 	    while (*p != NUL && (inquote || (*p != ' ' && *p != TAB)))
 	    {
-		if (*p == '"')
+		if (p[0] == '"')
 		    inquote = !inquote;
+		else if (p[0] == '\\' && p[1] != NUL)
+		{
+		    /* First pass: skip over "\ " and "\"".
+		     * Second pass: Remove the backslash. */
+		    if (i == 1)
+			mch_memmove(p, p + 1, STRLEN(p));
+		    else
+			++p;
+		}
 		++p;
 	    }
 	    if (*p == NUL)

src/testdir/test_terminal.vim

@@ -293,6 +293,8 @@ func Test_terminal_size()
   let size = term_getsize('')
   bwipe!
   call assert_equal([7, 27], size)
+
+  call delete('Xtext')
 endfunc
 
 func Test_terminal_curwin()
@@ -325,7 +327,7 @@ func Test_terminal_curwin()
 
   split dummy
   bwipe!
-
+  call delete('Xtext')
 endfunc
 
 func Test_finish_open_close()
@@ -555,3 +557,19 @@ func Test_terminal_no_cmd()
   call assert_equal('look here', term_getline(buf, 1))
   bwipe!
 endfunc
+
+func Test_terminal_special_chars()
+  " this file name only works on Unix
+  if !has('unix')
+    return
+  endif
+  call mkdir('Xdir with spaces')
+  call writefile(['x'], 'Xdir with spaces/quoted"file')
+  term ls Xdir\ with\ spaces/quoted\"file
+  call WaitFor('term_getline("", 1) =~ "quoted"')
+  call assert_match('quoted"file', term_getline('', 1))
+  call term_wait('')
+
+  call delete('Xdir with spaces', 'rf')
+  bwipe
+endfunc

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1051,
 /**/
     1050,
 /**/