patch 8.1.0112: no error when using bad arguments with searchpair()

Problem:    No error when using bad arguments with searchpair().
Solution:   Add error messages.

src/evalfunc.c

@@ -10152,7 +10152,8 @@ searchpair_cmn(typval_T *argvars, pos_T *match_pos)
     long	lnum_stop = 0;
     long	time_limit = 0;
 
-    /* Get the three pattern arguments: start, middle, end. */
+    /* Get the three pattern arguments: start, middle, end. Will result in an
+     * error if not a valid argument. */
     spat = get_tv_string_chk(&argvars[0]);
     mpat = get_tv_string_buf_chk(&argvars[1], nbuf1);
     epat = get_tv_string_buf_chk(&argvars[2], nbuf2);
@@ -10189,19 +10190,26 @@ searchpair_cmn(typval_T *argvars, pos_T *match_pos)
 	    && skip->v_type != VAR_STRING)
 	{
 	    /* Type error */
+	    EMSG2(_(e_invarg2), get_tv_string(&argvars[4]));
 	    goto theend;
 	}
 	if (argvars[5].v_type != VAR_UNKNOWN)
 	{
 	    lnum_stop = (long)get_tv_number_chk(&argvars[5], NULL);
 	    if (lnum_stop < 0)
+	    {
+		EMSG2(_(e_invarg2), get_tv_string(&argvars[5]));
 		goto theend;
+	    }
 #ifdef FEAT_RELTIME
 	    if (argvars[6].v_type != VAR_UNKNOWN)
 	    {
 		time_limit = (long)get_tv_number_chk(&argvars[6], NULL);
 		if (time_limit < 0)
+		{
+		    EMSG2(_(e_invarg2), get_tv_string(&argvars[6]));
 		    goto theend;
+		}
 	    }
 #endif
 	}

src/testdir/test_search.vim

@@ -287,16 +287,26 @@ func Test_searchpair()
   new
   call setline(1, ['other code here', '', '[', '" cursor here', ']'])
   4
-  let a=searchpair('\[','',']','bW')
+  let a = searchpair('\[','',']','bW')
   call assert_equal(3, a)
   set nomagic
   4
-  let a=searchpair('\[','',']','bW')
+  let a = searchpair('\[','',']','bW')
   call assert_equal(3, a)
   set magic
   q!
 endfunc
 
+func Test_searchpair_errors()
+  call assert_fails("call searchpair([0], 'middle', 'end', 'bW', 'skip', 99, 100)", 'E730: using List as a String')
+  call assert_fails("call searchpair('start', {-> 0}, 'end', 'bW', 'skip', 99, 100)", 'E729: using Funcref as a String')
+  call assert_fails("call searchpair('start', 'middle', {'one': 1}, 'bW', 'skip', 99, 100)", 'E731: using Dictionary as a String')
+  call assert_fails("call searchpair('start', 'middle', 'end', 'flags', 'skip', 99, 100)", 'E475: Invalid argument: flags')
+  call assert_fails("call searchpair('start', 'middle', 'end', 'bW', 0, 99, 100)", 'E475: Invalid argument: 0')
+  call assert_fails("call searchpair('start', 'middle', 'end', 'bW', 'func', -99, 100)", 'E475: Invalid argument: -99')
+  call assert_fails("call searchpair('start', 'middle', 'end', 'bW', 'func', 99, -100)", 'E475: Invalid argument: -100')
+endfunc
+
 func Test_searchpair_skip()
     func Zero()
 	return 0
@@ -311,8 +321,6 @@ func Test_searchpair_skip()
     3 | call assert_equal(1, searchpair('{', '', '}', 'bWn', {-> 0}))
     3 | call assert_equal(1, searchpair('{', '', '}', 'bWn', function('Zero')))
     3 | call assert_equal(1, searchpair('{', '', '}', 'bWn', function('Partial', [0])))
-    " invalid argument
-    3 | call assert_equal(0, searchpair('{', '', '}', 'bWn', 0))
     bw!
 endfunc
 

src/version.c

@@ -789,6 +789,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    112,
 /**/
     111,
 /**/