vim-patch:8.2.0953: spell checking doesn't work for CamelCased words

Problem:    Spell checking doesn't work for CamelCased words.
Solution:   Add the "camel" value in the new option 'spelloptions'.
            (closes vim/vim#1235)
362b44bd4a

runtime/doc/options.txt

@@ -5672,6 +5672,14 @@ A jump table for the options with a short description can be found at |Q_op|.
 	up to the first character that is not an ASCII letter or number and
 	not a dash.  Also see |set-spc-auto|.
 
+						*'spelloptions'* *'spo'*
+'spelloptions' 'spo'	string	(default "")
+			local to buffer
+	A comma separated list of options for spell checking:
+	   camel	When a word is CamelCased, assume "Cased" is a
+			separate word: every upper-case character in a word
+			that comes after a lower case character indicates the
+			start of a new word.
 
 						*'spellsuggest'* *'sps'*
 'spellsuggest' 'sps'	string	(default "best")

runtime/doc/spell.txt

@@ -187,6 +187,9 @@ When there is a line break right after a sentence the highlighting of the next
 line may be postponed.  Use |CTRL-L| when needed.  Also see |set-spc-auto| for
 how it can be set automatically when 'spelllang' is set.
 
+The 'spelloptions' option has a few more flags that influence the way spell
+checking works.
+
 Vim counts the number of times a good word is encountered.  This is used to
 sort the suggestions: words that have been seen before get a small bonus,
 words that have been seen often get a bigger bonus.  The COMMON item in the

src/nvim/buffer.c

@@ -1941,6 +1941,7 @@ void free_buf_options(buf_T *buf, int free_p_ff)
   vim_regfree(buf->b_s.b_cap_prog);
   buf->b_s.b_cap_prog = NULL;
   clear_string_option(&buf->b_s.b_p_spl);
+  clear_string_option(&buf->b_s.b_p_spo);
   clear_string_option(&buf->b_p_sua);
   clear_string_option(&buf->b_p_ft);
   clear_string_option(&buf->b_p_cink);

src/nvim/option.c

@@ -174,6 +174,7 @@ static char_u   *p_syn;
 static char_u   *p_spc;
 static char_u   *p_spf;
 static char_u   *p_spl;
+static char_u   *p_spo;
 static long p_ts;
 static long p_tw;
 static int p_udf;
@@ -2285,6 +2286,7 @@ void check_buf_options(buf_T *buf)
   check_string_option(&buf->b_s.b_p_spc);
   check_string_option(&buf->b_s.b_p_spf);
   check_string_option(&buf->b_s.b_p_spl);
+  check_string_option(&buf->b_s.b_p_spo);
   check_string_option(&buf->b_p_sua);
   check_string_option(&buf->b_p_cink);
   check_string_option(&buf->b_p_cino);
@@ -3090,6 +3092,10 @@ ambw_end:
   } else if (varp == &(curwin->w_s->b_p_spc)) {
     // When 'spellcapcheck' is set compile the regexp program.
     errmsg = compile_cap_prog(curwin->w_s);
+  } else if (varp == &(curwin->w_s->b_p_spo)) {  // 'spelloptions'
+    if (**varp != NUL && STRCMP("camel", *varp) != 0) {
+      errmsg = e_invarg;
+    }
   } else if (varp == &p_sps) {  // 'spellsuggest'
     if (spell_check_sps() != OK) {
       errmsg = e_invarg;
@@ -5896,6 +5902,7 @@ static char_u *get_varp(vimoption_T *p)
   case PV_SPC:    return (char_u *)&(curwin->w_s->b_p_spc);
   case PV_SPF:    return (char_u *)&(curwin->w_s->b_p_spf);
   case PV_SPL:    return (char_u *)&(curwin->w_s->b_p_spl);
+  case PV_SPO:    return (char_u *)&(curwin->w_s->b_p_spo);
   case PV_SW:     return (char_u *)&(curbuf->b_p_sw);
   case PV_TFU:    return (char_u *)&(curbuf->b_p_tfu);
   case PV_TS:     return (char_u *)&(curbuf->b_p_ts);
@@ -6175,6 +6182,7 @@ void buf_copy_options(buf_T *buf, int flags)
       (void)compile_cap_prog(&buf->b_s);
       buf->b_s.b_p_spf = vim_strsave(p_spf);
       buf->b_s.b_p_spl = vim_strsave(p_spl);
+      buf->b_s.b_p_spo = vim_strsave(p_spo);
       buf->b_p_inde = vim_strsave(p_inde);
       buf->b_p_indk = vim_strsave(p_indk);
       buf->b_p_fp = empty_option;

src/nvim/option_defs.h

@@ -787,6 +787,7 @@ enum {
   , BV_SPC
   , BV_SPF
   , BV_SPL
+  , BV_SPO
   , BV_STS
   , BV_SUA
   , BV_SW

src/nvim/options.lua

@@ -2319,6 +2319,16 @@ return {
       varname='p_sps',
       defaults={if_true={vi="best"}}
     },
+    {
+      full_name='spelloptions', abbreviation='spo',
+      type='string', list='onecomma', scope={'buffer'},
+      deny_duplicates=true,
+      secure=true,
+      vi_def=true,
+      expand=true,
+      varname='p_spo',
+      defaults={if_true={vi="", vim=""}}
+    },
     {
       full_name='splitbelow', abbreviation='sb',
       type='bool', scope={'global'},

src/nvim/testdir/test_spell.vim

@@ -79,6 +79,11 @@ func Test_spellbadword()
   call assert_equal(['bycycle', 'bad'],  spellbadword('My bycycle.'))
   call assert_equal(['another', 'caps'], spellbadword('A sentence. another sentence'))
 
+  call assert_equal(['TheCamelWord', 'bad'], spellbadword('TheCamelWord asdf'))
+  set spelloptions=camel
+  call assert_equal(['asdf', 'bad'], spellbadword('TheCamelWord asdf'))
+  set spelloptions=
+
   set spelllang=en
   call assert_equal(['', ''],            spellbadword('centre'))
   call assert_equal(['', ''],            spellbadword('center'))