patch 9.0.1973: Clean up cmdline option completion code

Problem:  Clean up cmdline option completion code
Solution: Fix various minor problems

- Fix manual array size calculations to just use `ARRAY_LENGTH()`.
- Fix unintentional typo in comments due to copy-paste error.
- Fix assert_equal() usages to pass the expected value to first
  parameter instead of 2nd one to avoid confusion.
- Fix signed vs unsigned warnings
- Correct misplaced comments about set_op_T and set_prefix_T
  and fix a typo in another comment

closes: #13249
closes: #13237

Signed-off-by: Christian Brabandt <[email protected]>
Co-authored-by: Yee Cheng Chin <[email protected]>
Co-authored-by: zeertzjq <[email protected]>

Author: 2 people

src/move.c

@@ -3587,7 +3587,7 @@ do_check_cursorbind(void)
     FOR_ALL_WINDOWS(curwin)
     {
 	curbuf = curwin->w_buffer;
-	// skip original window  and windows with 'noscrollbind'
+	// skip original window and windows with 'nocursorbind'
 	if (curwin != old_curwin && curwin->w_p_crb)
 	{
 # ifdef FEAT_DIFF

src/option.c

@@ -1312,7 +1312,7 @@ ex_set(exarg_T *eap)
 }
 
 /*
- * :set operator types
+ * :set boolean option prefix
  */
 typedef enum {
     PREFIX_NO = 0,	// "no" prefix
@@ -1830,7 +1830,7 @@ stropt_get_newval(
 					     &(options[opt_idx]), OPT_GLOBAL));
     else
     {
-	++arg;	// joption_value2stringump to after the '=' or ':'
+	++arg;	// jump to after the '=' or ':'
 
 	// Set 'keywordprg' to ":help" if an empty
 	// value was passed to :set by the user.
@@ -7991,7 +7991,7 @@ ExpandSettingSubtract(
 	    return FAIL;
 	}
 
-	int num_flags = STRLEN(option_val);
+	size_t num_flags = STRLEN(option_val);
 	if (num_flags == 0)
 	    return FAIL;