vim-patch:8.2.4702: C++ scope labels are hard-coded

Problem:    C++ scope labels are hard-coded.
Solution:   Add 'cinscopedecls' to define the labels. (Tom Praschan,
            closes vim/vim#10109)
https://github.com/vim/vim/commit/3506cf34c17c5eae6c2d1317db1fcd5a8493c288

11 files changed, 100 insertions, 20 deletions

diff --git a/runtime/doc/indent.txt b/runtime/doc/indent.txt
index d0d4ddad32..3992b2d3d7 100644
--- a/runtime/doc/indent.txt
+++ b/runtime/doc/indent.txt
@@ -38,11 +38,12 @@ is not a C compiler: it does not recognize all syntax.  One requirement is
 that toplevel functions have a '{' in the first column.  Otherwise they are
 easily confused with declarations.
 
-These four options control C program indenting:
+These five options control C program indenting:
 'cindent'	Enables Vim to perform C program indenting automatically.
 'cinkeys'	Specifies which keys trigger reindenting in insert mode.
 'cinoptions'	Sets your preferred indent style.
 'cinwords'	Defines keywords that start an extra indent in the next line.
+'cinscopedecls'	Defines strings that are recognized as a C++ scope declaration.
 
 If 'lisp' is not on and 'equalprg' is empty, the "=" operator indents using
 Vim's built-in algorithm rather than calling an external program.
@@ -289,8 +290,9 @@ The examples below assume a 'shiftwidth' of 4.
 <
 							*cino-g*
 	gN    Place C++ scope declarations N characters from the indent of the
-	      block they are in.  (default 'shiftwidth').  A scope declaration
-	      can be "public:", "protected:" or "private:".
+	      block they are in.  (default 'shiftwidth'). By default, a scope 
+	      declaration is "public:", "protected:" or "private:". This can
+	      be adjusted with the 'cinscopedecls' option.
 
 		cino=		    cino=g0 >
 		  {		      {
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index b60b8f8849..123577778f 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1288,10 +1288,20 @@ A jump table for the options with a short description can be found at |Q_op|.
 	matter, include the keyword both the uppercase and lowercase:
 	"if,If,IF".
 
-						*'clipboard'* *'cb'*
+						*'cinscopedecls'* *'cinsd'*
+'cinscopedecls' 'cinsd'	string	(default "public,protected,private")
+			local to buffer
+			{not available when compiled without the |+cindent|
+			feature}
+	Keywords that are interpreted as a C++ scope declaration by |cino-g|.
+	Useful e.g. for working with the Qt framework that defines additional
+	scope declarations "signals", "public slots" and "private slots": >
+		set cinscopedecls+=signals,public\ slots,private\ slots
+
+<						*'clipboard'* *'cb'*
 'clipboard' 'cb'	string	(default "")
 			global
-	This option is a list of comma separated names.
+	This option is a list of comma-separated names.
 	These names are recognized:
 
 						*clipboard-unnamed*
diff --git a/runtime/doc/quickref.txt b/runtime/doc/quickref.txt
index e36eb2359f..c3badd5401 100644
--- a/runtime/doc/quickref.txt
+++ b/runtime/doc/quickref.txt
@@ -638,6 +638,7 @@ Short explanation of each option:		*option-list*
 'cinkeys'	  'cink'    keys that trigger indent when 'cindent' is set
 'cinoptions'	  'cino'    how to do indenting when 'cindent' is set
 'cinwords'	  'cinw'    words where 'si' and 'cin' add an indent
+'cinscopedecls'	  'cinsd'   words that are recognized by 'cino-g' 
 'clipboard'	  'cb'	    use the clipboard as the unnamed register
 'cmdheight'	  'ch'	    number of lines to use for the command-line
 'cmdwinheight'	  'cwh'     height of the command-line window
diff --git a/runtime/optwin.vim b/runtime/optwin.vim
index c873252909..0e3f2d935e 100644
--- a/runtime/optwin.vim
+++ b/runtime/optwin.vim
@@ -870,6 +870,9 @@ if has("cindent")
   call append("$", "cinwords\tlist of words that cause more C-indent")
   call append("$", "\t(local to buffer)")
   call <SID>OptionL("cinw")
+  call append("$", "cinscopedecls\tlist of scope declaration names used by cino-g")
+  call append("$", "\t(local to buffer)")
+  call <SID>OptionL("cinsd")
   call append("$", "indentexpr\texpression used to obtain the indent of a line")
   call append("$", "\t(local to buffer)")
   call <SID>OptionL("inde")
diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index bf592a626d..b65fa77660 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -1938,6 +1938,7 @@ void free_buf_options(buf_T *buf, int free_p_ff)
   clear_string_option(&buf->b_p_cink);
   clear_string_option(&buf->b_p_cino);
   clear_string_option(&buf->b_p_cinw);
+  clear_string_option(&buf->b_p_cinsd);
   clear_string_option(&buf->b_p_cpt);
   clear_string_option(&buf->b_p_cfu);
   clear_string_option(&buf->b_p_ofu);
diff --git a/src/nvim/buffer_defs.h b/src/nvim/buffer_defs.h
index 422741cc2f..2bb45e9fa0 100644
--- a/src/nvim/buffer_defs.h
+++ b/src/nvim/buffer_defs.h
@@ -696,6 +696,7 @@ struct file_buffer {
   char_u *b_p_cino;             ///< 'cinoptions'
   char_u *b_p_cink;             ///< 'cinkeys'
   char_u *b_p_cinw;             ///< 'cinwords'
+  char_u *b_p_cinsd;            ///< 'cinscopedecls'
   char_u *b_p_com;              ///< 'comments'
   char_u *b_p_cms;              ///< 'commentstring'
   char_u *b_p_cpt;              ///< 'complete'
diff --git a/src/nvim/indent_c.c b/src/nvim/indent_c.c
index 7f483d02ab..d26a27c1c2 100644
--- a/src/nvim/indent_c.c
+++ b/src/nvim/indent_c.c
@@ -512,24 +512,27 @@ static int cin_isdefault(const char_u *s)
          && s[1] != ':';
 }
 
-/*
- * Recognize a "public/private/protected" scope declaration label.
- */
-bool cin_isscopedecl(const char_u *s)
+/// Recognize a scope declaration label set in 'cinscopedecls'.
+bool cin_isscopedecl(const char_u *p)
 {
-  int i;
+  const char_u *s = cin_skipcomment(p);
 
-  s = cin_skipcomment(s);
-  if (STRNCMP(s, "public", 6) == 0) {
-    i = 6;
-  } else if (STRNCMP(s, "protected", 9) == 0) {
-    i = 9;
-  } else if (STRNCMP(s, "private", 7) == 0) {
-    i = 7;
-  } else {
-    return false;
+  const size_t cinsd_len = STRLEN(curbuf->b_p_cinsd) + 1;
+  char_u *cinsd_buf = xmalloc(cinsd_len);
+
+  for (char_u *cinsd = curbuf->b_p_cinsd; *cinsd; ) {
+    const size_t len = copy_option_part(&cinsd, cinsd_buf, cinsd_len, ",");
+    if (STRNCMP(s, cinsd_buf, len) == 0) {
+      const char_u *skip = cin_skipcomment(s + len);
+      if (*skip == ':' && skip[1] != ':') {
+        return true;
+      }
+    }
   }
-  return *(s = cin_skipcomment(s + i)) == ':' && s[1] != ':';
+
+  xfree(cinsd_buf);
+
+  return false;
 }
 
 // Maximum number of lines to search back for a "namespace" line.
diff --git a/src/nvim/option.c b/src/nvim/option.c
index 9fd0e0b222..6522454aa5 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -133,6 +133,7 @@ static int p_cin;
 static char_u *p_cink;
 static char_u *p_cino;
 static char_u *p_cinw;
+static char_u *p_cinsd;
 static char_u *p_com;
 static char_u *p_cms;
 static char_u *p_cpt;
@@ -2060,6 +2061,7 @@ void check_buf_options(buf_T *buf)
   parse_cino(buf);
   check_string_option(&buf->b_p_ft);
   check_string_option(&buf->b_p_cinw);
+  check_string_option(&buf->b_p_cinsd);
   check_string_option(&buf->b_p_cpt);
   check_string_option(&buf->b_p_cfu);
   check_string_option(&buf->b_p_ofu);
@@ -6058,6 +6060,8 @@ static char_u *get_varp(vimoption_T *p)
     return (char_u *)&(curbuf->b_p_cink);
   case PV_CINO:
     return (char_u *)&(curbuf->b_p_cino);
+  case PV_CINSD:
+    return (char_u *)&(curbuf->b_p_cinsd);
   case PV_CINW:
     return (char_u *)&(curbuf->b_p_cinw);
   case PV_COM:
@@ -6505,6 +6509,8 @@ void buf_copy_options(buf_T *buf, int flags)
       COPY_OPT_SCTX(buf, BV_CINK);
       buf->b_p_cino = vim_strsave(p_cino);
       COPY_OPT_SCTX(buf, BV_CINO);
+      buf->b_p_cinsd = vim_strsave(p_cinsd);
+      COPY_OPT_SCTX(buf, BV_CINSD);
       // Don't copy 'filetype', it must be detected
       buf->b_p_ft = empty_option;
       buf->b_p_pi = p_pi;
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index 6ce95ea690..bf71b63cc8 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -773,6 +773,7 @@ enum {
   BV_CINK,
   BV_CINO,
   BV_CINW,
+  BV_CINSD,
   BV_CM,
   BV_CMS,
   BV_COM,
diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index e665ffd346..313cace4b2 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -351,6 +351,15 @@ return {
       defaults={if_true="if,else,while,do,for,switch"}
     },
     {
+      full_name='cinscopedecls', abbreviation='cinsd',
+      short_desc=N_("words that are recognized by 'cino-g'"),
+      type='string', list='onecomma', scope={'buffer'},
+      deny_duplicates=true,
+      alloced=true,
+      varname='p_cinsd',
+      defaults={if_true="public,protected,private"}
+    },
+    {
       full_name='clipboard', abbreviation='cb',
       short_desc=N_("use the clipboard as the unnamed register"),
       type='string', list='onecomma', scope={'global'},
diff --git a/src/nvim/testdir/test_cindent.vim b/src/nvim/testdir/test_cindent.vim
index 4b702bf2b8..4d69aed96c 100644
--- a/src/nvim/testdir/test_cindent.vim
+++ b/src/nvim/testdir/test_cindent.vim
@@ -5311,6 +5311,49 @@ func Test_cindent_case()
   bwipe!
 endfunc
 
+func Test_cindent_scopedecls()
+  new
+  setl cindent ts=4 sw=4
+  setl cino=g0
+  setl cinsd+=public\ slots,signals
+
+  let code =<< trim [CODE]
+  class Foo
+  {
+  public:
+  virtual void foo() = 0;
+  public slots:
+  void onBar();
+  signals:
+  void baz();
+  private:
+  int x;
+  };
+  [CODE]
+
+  call append(0, code)
+  normal gg
+  normal ]]=][
+
+  let expected =<< trim [CODE]
+  class Foo
+  {
+  public:
+	virtual void foo() = 0;
+  public slots:
+	void onBar();
+  signals:
+	void baz();
+  private:
+	int x;
+  };
+
+  [CODE]
+
+  call assert_equal(expected, getline(1, '$'))
+  enew! | close
+endfunc
+
 func Test_cindent_pragma()
   new
   setl cindent ts=4 sw=4