patch 9.0.1262: the did_set_string_option function is too long

Problem:    The did_set_string_option function is too long.
Solution:   Split off functionality to individual functions.  (Yegappan
            Lakshmanan, Lewis Russell, closes #11904)

src/gui_xim.c

@@ -73,16 +73,22 @@ xim_log(char *s, ...)
 static callback_T imaf_cb;	    // 'imactivatefunc' callback function
 static callback_T imsf_cb;	    // 'imstatusfunc' callback function
 
-    int
+    char *
 set_imactivatefunc_option(void)
 {
-    return option_set_callback_func(p_imaf, &imaf_cb);
+    if (option_set_callback_func(p_imaf, &imaf_cb) == FAIL)
+	return e_invalid_argument;
+
+    return NULL;
 }
 
-    int
+    char *
 set_imstatusfunc_option(void)
 {
-    return option_set_callback_func(p_imsf, &imsf_cb);
+    if (option_set_callback_func(p_imsf, &imsf_cb) == FAIL)
+	return e_invalid_argument;
+
+    return NULL;
 }
 
     static void

src/insexpand.c

@@ -2545,16 +2545,15 @@ copy_global_to_buflocal_cb(callback_T *globcb, callback_T *bufcb)
  * name of a function (string), or function(<name>) or funcref(<name>) or a
  * lambda expression.
  */
-    int
+    char *
 set_completefunc_option(void)
 {
-    int	retval;
+    if (option_set_callback_func(curbuf->b_p_cfu, &cfu_cb) == FAIL)
+	return e_invalid_argument;
 
-    retval = option_set_callback_func(curbuf->b_p_cfu, &cfu_cb);
-    if (retval == OK)
-	set_buflocal_cfu_callback(curbuf);
+    set_buflocal_cfu_callback(curbuf);
 
-    return retval;
+    return NULL;
 }
 
 /*
@@ -2575,16 +2574,14 @@ set_buflocal_cfu_callback(buf_T *buf UNUSED)
  * name of a function (string), or function(<name>) or funcref(<name>) or a
  * lambda expression.
  */
-    int
+    char *
 set_omnifunc_option(void)
 {
-    int	retval;
+    if (option_set_callback_func(curbuf->b_p_ofu, &ofu_cb) == FAIL)
+	return e_invalid_argument;
 
-    retval = option_set_callback_func(curbuf->b_p_ofu, &ofu_cb);
-    if (retval == OK)
-	set_buflocal_ofu_callback(curbuf);
-
-    return retval;
+    set_buflocal_ofu_callback(curbuf);
+    return NULL;
 }
 
 /*
@@ -2605,7 +2602,7 @@ set_buflocal_ofu_callback(buf_T *buf UNUSED)
  * name of a function (string), or function(<name>) or funcref(<name>) or a
  * lambda expression.
  */
-    int
+    char *
 set_thesaurusfunc_option(void)
 {
     int	retval;
@@ -2622,7 +2619,7 @@ set_thesaurusfunc_option(void)
 	retval = option_set_callback_func(p_tsrfu, &tsrfu_cb);
     }
 
-    return retval;
+    return retval == FAIL ? e_invalid_argument : NULL;
 }
 
 /*

src/ops.c

@@ -3405,10 +3405,13 @@ static callback_T opfunc_cb;
  * Process the 'operatorfunc' option value.
  * Returns OK or FAIL.
  */
-    int
+    char *
 set_operatorfunc_option(void)
 {
-    return option_set_callback_func(p_opfunc, &opfunc_cb);
+    if (option_set_callback_func(p_opfunc, &opfunc_cb) == FAIL)
+	return e_invalid_argument;
+
+    return NULL;
 }
 
 #if defined(EXITFREE) || defined(PROTO)

src/proto/gui_xim.pro

@@ -1,6 +1,6 @@
 /* gui_xim.c */
-int set_imactivatefunc_option(void);
-int set_imstatusfunc_option(void);
+char *set_imactivatefunc_option(void);
+char *set_imstatusfunc_option(void);
 void free_xim_stuff(void);
 int set_ref_in_im_funcs(int copyID);
 void im_set_active(int active);

src/proto/insexpand.pro

@@ -44,11 +44,11 @@ int ins_compl_bs(void);
 void ins_compl_addleader(int c);
 void ins_compl_addfrommatch(void);
 int ins_compl_prep(int c);
-int set_completefunc_option(void);
+char *set_completefunc_option(void);
 void set_buflocal_cfu_callback(buf_T *buf);
-int set_omnifunc_option(void);
+char *set_omnifunc_option(void);
 void set_buflocal_ofu_callback(buf_T *buf);
-int set_thesaurusfunc_option(void);
+char *set_thesaurusfunc_option(void);
 int set_ref_in_insexpand_funcs(int copyID);
 void f_complete(typval_T *argvars, typval_T *rettv);
 void f_complete_add(typval_T *argvars, typval_T *rettv);

src/proto/ops.pro

@@ -17,7 +17,7 @@ void block_prep(oparg_T *oap, struct block_def *bdp, linenr_T lnum, int is_del);
 void op_addsub(oparg_T *oap, linenr_T Prenum1, int g_cmd);
 void clear_oparg(oparg_T *oap);
 void cursor_pos_info(dict_T *dict);
-int set_operatorfunc_option(void);
+char *set_operatorfunc_option(void);
 void free_operatorfunc_option(void);
 int set_ref_in_opfunc(int copyID);
 void do_pending_operator(cmdarg_T *cap, int old_col, int gui_yank);

src/proto/quickfix.pro

@@ -15,7 +15,7 @@ void ex_cclose(exarg_T *eap);
 void ex_copen(exarg_T *eap);
 void ex_cbottom(exarg_T *eap);
 linenr_T qf_current_entry(win_T *wp);
-int qf_process_qftf_option(void);
+char *qf_process_qftf_option(void);
 int grep_internal(cmdidx_T cmdidx);
 void ex_make(exarg_T *eap);
 int qf_get_size(exarg_T *eap);

src/proto/tag.pro

@@ -1,5 +1,5 @@
 /* tag.c */
-int set_tagfunc_option(void);
+char *set_tagfunc_option(void);
 void free_tagfunc_option(void);
 int set_ref_in_tagfunc(int copyID);
 void set_buflocal_tfu_callback(buf_T *buf);

src/quickfix.c

@@ -4533,10 +4533,13 @@ qf_find_buf(qf_info_T *qi)
  * Process the 'quickfixtextfunc' option value.
  * Returns OK or FAIL.
  */
-    int
+    char *
 qf_process_qftf_option(void)
 {
-    return option_set_callback_func(p_qftf, &qftf_cb);
+    if (option_set_callback_func(p_qftf, &qftf_cb) == FAIL)
+	return e_invalid_argument;
+
+    return NULL;
 }
 
 /*

src/spell.c

@@ -4386,7 +4386,7 @@ valid_spellfile(char_u *val)
 }
 
 /*
- * Handle side effects of setting 'spell'.
+ * Handle side effects of setting 'spell' or 'spellfile'
  * Return an error message or NULL for success.
  */
     char *

src/tag.c

@@ -170,7 +170,7 @@ static callback_T tfu_cb;	    // 'tagfunc' callback function
  * Invoked when the 'tagfunc' option is set. The option value can be a name of
  * a function (string), or function(<name>) or funcref(<name>) or a lambda.
  */
-    int
+    char *
 set_tagfunc_option(void)
 {
 #ifdef FEAT_EVAL
@@ -178,15 +178,15 @@ set_tagfunc_option(void)
     free_callback(&curbuf->b_tfu_cb);
 
     if (*curbuf->b_p_tfu == NUL)
-	return OK;
+	return NULL;
 
     if (option_set_callback_func(curbuf->b_p_tfu, &tfu_cb) == FAIL)
-	return FAIL;
+	return e_invalid_argument;
 
     copy_callback(&curbuf->b_tfu_cb, &tfu_cb);
 #endif
 
-    return OK;
+    return NULL;
 }
 #endif
 

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1262,
 /**/
     1261,
 /**/