patch 8.0.0186: confusing error message from assert_notequal()

Problem:    The error message from assert_notequal() is confusing.
Solution:   Only mention the expected value.

Author: brammool

src/eval.c

@@ -9256,6 +9256,8 @@ fill_assert_error(
     {
 	if (atype == ASSERT_MATCH || atype == ASSERT_NOTMATCH)
 	    ga_concat(gap, (char_u *)"Pattern ");
+	else if (atype == ASSERT_NOTEQUAL)
+	    ga_concat(gap, (char_u *)"Expected not equal to ");
 	else
 	    ga_concat(gap, (char_u *)"Expected ");
 	if (exp_str == NULL)
@@ -9265,16 +9267,17 @@ fill_assert_error(
 	}
 	else
 	    ga_concat_esc(gap, exp_str);
-	if (atype == ASSERT_MATCH)
-	    ga_concat(gap, (char_u *)" does not match ");
-	else if (atype == ASSERT_NOTMATCH)
-	    ga_concat(gap, (char_u *)" does match ");
-	else if (atype == ASSERT_NOTEQUAL)
-	    ga_concat(gap, (char_u *)" differs from ");
-	else
-	    ga_concat(gap, (char_u *)" but got ");
-	ga_concat_esc(gap, tv2string(got_tv, &tofree, numbuf, 0));
-	vim_free(tofree);
+	if (atype != ASSERT_NOTEQUAL)
+	{
+	    if (atype == ASSERT_MATCH)
+		ga_concat(gap, (char_u *)" does not match ");
+	    else if (atype == ASSERT_NOTMATCH)
+		ga_concat(gap, (char_u *)" does match ");
+	    else
+		ga_concat(gap, (char_u *)" but got ");
+	    ga_concat_esc(gap, tv2string(got_tv, &tofree, numbuf, 0));
+	    vim_free(tofree);
+	}
     }
 }
 

src/testdir/test_assert.vim

@@ -32,7 +32,7 @@ func Test_assert_notequal()
   call assert_notequal([1, 2, 3], s)
 
   call assert_notequal('foo', s)
-  call assert_match("Expected 'foo' differs from 'foo'", v:errors[0])
+  call assert_match("Expected not equal to 'foo'", v:errors[0])
   call remove(v:errors, 0)
 endfunc
 

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    186,
 /**/
     185,
 /**/