patch 8.1.1068: cannot get all the information about current completion

Problem:    Cannot get all the information about current completion.
Solution:   Add complete_info(). (Shougo, Hirohito Higashi, closes #4106)
diff --git a/src/edit.c b/src/edit.c
index f15ee8d..dcead23 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -15,7 +15,9 @@
 
 #ifdef FEAT_INS_EXPAND
 /*
- * definitions used for CTRL-X submode
+ * Definitions used for CTRL-X submode.
+ * Note: If you change CTRL-X submode, you must also maintain ctrl_x_msgs[] and
+ * ctrl_x_mode_names[].
  */
 # define CTRL_X_WANT_IDENT	0x100
 
@@ -40,18 +42,18 @@
 # define CTRL_X_MSG(i) ctrl_x_msgs[(i) & ~CTRL_X_WANT_IDENT]
 # define CTRL_X_MODE_LINE_OR_EVAL(m) ((m) == CTRL_X_WHOLE_LINE || (m) == CTRL_X_EVAL)
 
-/* Message for CTRL-X mode, index is ctrl_x_mode. */
+// Message for CTRL-X mode, index is ctrl_x_mode.
 static char *ctrl_x_msgs[] =
 {
-    N_(" Keyword completion (^N^P)"), /* CTRL_X_NORMAL, ^P/^N compl. */
+    N_(" Keyword completion (^N^P)"), // CTRL_X_NORMAL, ^P/^N compl.
     N_(" ^X mode (^]^D^E^F^I^K^L^N^O^Ps^U^V^Y)"),
-    NULL, /* CTRL_X_SCROLL: depends on state */
+    NULL, // CTRL_X_SCROLL: depends on state
     N_(" Whole line completion (^L^N^P)"),
     N_(" File name completion (^F^N^P)"),
     N_(" Tag completion (^]^N^P)"),
     N_(" Path pattern completion (^N^P)"),
     N_(" Definition completion (^D^N^P)"),
-    NULL, /* CTRL_X_FINISHED */
+    NULL, // CTRL_X_FINISHED
     N_(" Dictionary completion (^K^N^P)"),
     N_(" Thesaurus completion (^T^N^P)"),
     N_(" Command-line completion (^V^N^P)"),
@@ -59,9 +61,30 @@
     N_(" Omni completion (^O^N^P)"),
     N_(" Spelling suggestion (s^N^P)"),
     N_(" Keyword Local completion (^N^P)"),
-    NULL,   /* CTRL_X_EVAL doesn't use msg. */
+    NULL,   // CTRL_X_EVAL doesn't use msg.
 };
 
+static char *ctrl_x_mode_names[] = {
+	"keyword",
+	"ctrl_x",
+	"unknown",	    // CTRL_X_SCROLL
+	"whole_line",
+	"files",
+	"tags",
+	"path_patterns",
+	"path_defines",
+	"unknown",	    // CTRL_X_FINISHED
+	"dictionary",
+	"thesaurus",
+	"cmdline",
+	"function",
+	"omni",
+	"spell",
+	NULL,		    // CTRL_X_LOCAL_MSG only used in "ctrl_x_msgs"
+	"eval"
+    };
+
+
 static char e_hitend[] = N_("Hit end of paragraph");
 # ifdef FEAT_COMPL_FUNC
 static char e_complwin[] = N_("E839: Completion function changed window");
@@ -163,6 +186,7 @@
 static char_u *find_line_end(char_u *ptr);
 static void ins_compl_free(void);
 static void ins_compl_clear(void);
+static char_u *ins_compl_mode(void);
 static int  ins_compl_bs(void);
 static int  ins_compl_need_restart(void);
 static void ins_compl_new_leader(void);
@@ -3525,6 +3549,108 @@
     return compl_started;
 }
 
+
+/*
+ * Get complete information
+ */
+    void
+get_complete_info(list_T *what_list, dict_T *retdict)
+{
+    int		ret = OK;
+    listitem_T	*item;
+#define CI_WHAT_MODE		0x01
+#define CI_WHAT_PUM_VISIBLE	0x02
+#define CI_WHAT_ITEMS		0x04
+#define CI_WHAT_SELECTED	0x08
+#define CI_WHAT_INSERTED	0x10
+#define CI_WHAT_ALL		0xff
+    int		what_flag;
+
+    if (what_list == NULL)
+	what_flag = CI_WHAT_ALL;
+    else
+    {
+	what_flag = 0;
+	for (item = what_list->lv_first; item != NULL; item = item->li_next)
+	{
+	    char_u *what = tv_get_string(&item->li_tv);
+
+	    if (STRCMP(what, "mode") == 0)
+		what_flag |= CI_WHAT_MODE;
+	    else if (STRCMP(what, "pum_visible") == 0)
+		what_flag |= CI_WHAT_PUM_VISIBLE;
+	    else if (STRCMP(what, "items") == 0)
+		what_flag |= CI_WHAT_ITEMS;
+	    else if (STRCMP(what, "selected") == 0)
+		what_flag |= CI_WHAT_SELECTED;
+	    else if (STRCMP(what, "inserted") == 0)
+		what_flag |= CI_WHAT_INSERTED;
+	}
+    }
+
+    if (ret == OK && (what_flag & CI_WHAT_MODE))
+	ret = dict_add_string(retdict, "mode", ins_compl_mode());
+
+    if (ret == OK && (what_flag & CI_WHAT_PUM_VISIBLE))
+	ret = dict_add_number(retdict, "pum_visible", pum_visible());
+
+    if (ret == OK && (what_flag & CI_WHAT_ITEMS))
+    {
+	list_T	    *li;
+	dict_T	    *di;
+	compl_T     *match;
+
+	li = list_alloc();
+	if (li == NULL)
+	    return;
+	ret = dict_add_list(retdict, "items", li);
+	if (ret == OK && compl_first_match != NULL)
+	{
+	    match = compl_first_match;
+	    do
+	    {
+		if (!(match->cp_flags & ORIGINAL_TEXT))
+		{
+		    di = dict_alloc();
+		    if (di == NULL)
+			return;
+		    ret = list_append_dict(li, di);
+		    if (ret != OK)
+			return;
+		    dict_add_string(di, "word", match->cp_str);
+		    dict_add_string(di, "abbr", match->cp_text[CPT_ABBR]);
+		    dict_add_string(di, "menu", match->cp_text[CPT_MENU]);
+		    dict_add_string(di, "kind", match->cp_text[CPT_KIND]);
+		    dict_add_string(di, "info", match->cp_text[CPT_INFO]);
+		    dict_add_string(di, "user_data",
+					    match->cp_text[CPT_USER_DATA]);
+		}
+		match = match->cp_next;
+	    }
+	    while (match != NULL && match != compl_first_match);
+	}
+    }
+
+    if (ret == OK && (what_flag & CI_WHAT_SELECTED))
+	ret = dict_add_number(retdict, "selected", (compl_curr_match != NULL) ?
+			compl_curr_match->cp_number - 1 : -1);
+
+    // TODO
+    // if (ret == OK && (what_flag & CI_WHAT_INSERTED))
+}
+
+/*
+ * Return Insert completion mode name string
+ */
+    static char_u *
+ins_compl_mode(void)
+{
+    if (ctrl_x_mode == CTRL_X_NOT_DEFINED_YET || compl_started)
+	return (char_u *)ctrl_x_mode_names[ctrl_x_mode & ~CTRL_X_WANT_IDENT];
+
+    return (char_u *)"";
+}
+
 /*
  * Delete one character before the cursor and show the subset of the matches
  * that match the word that is now before the cursor.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index c1a32f3..6aff499 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -113,6 +113,7 @@
 static void f_complete(typval_T *argvars, typval_T *rettv);
 static void f_complete_add(typval_T *argvars, typval_T *rettv);
 static void f_complete_check(typval_T *argvars, typval_T *rettv);
+static void f_complete_info(typval_T *argvars, typval_T *rettv);
 #endif
 static void f_confirm(typval_T *argvars, typval_T *rettv);
 static void f_copy(typval_T *argvars, typval_T *rettv);
@@ -593,6 +594,7 @@
     {"complete",	2, 2, f_complete},
     {"complete_add",	1, 1, f_complete_add},
     {"complete_check",	0, 0, f_complete_check},
+    {"complete_info",	0, 1, f_complete_info},
 #endif
     {"confirm",		1, 4, f_confirm},
     {"copy",		1, 1, f_copy},
@@ -2600,6 +2602,29 @@
     rettv->vval.v_number = compl_interrupted;
     RedrawingDisabled = saved;
 }
+
+/*
+ * "complete_info()" function
+ */
+    static void
+f_complete_info(typval_T *argvars, typval_T *rettv)
+{
+    list_T	*what_list = NULL;
+
+    if (rettv_dict_alloc(rettv) != OK)
+	return;
+
+    if (argvars[0].v_type != VAR_UNKNOWN)
+    {
+	if (argvars[0].v_type != VAR_LIST)
+	{
+	    emsg(_(e_listreq));
+	    return;
+	}
+	what_list = argvars[0].vval.v_list;
+    }
+    get_complete_info(what_list, rettv->vval.v_dict);
+}
 #endif
 
 /*
diff --git a/src/proto/edit.pro b/src/proto/edit.pro
index 3a1573f..3f82bff 100644
--- a/src/proto/edit.pro
+++ b/src/proto/edit.pro
@@ -18,6 +18,7 @@
 char_u *find_word_start(char_u *ptr);
 char_u *find_word_end(char_u *ptr);
 int ins_compl_active(void);
+void get_complete_info(list_T *what_list, dict_T *retdict);
 int ins_compl_add_tv(typval_T *tv, int dir);
 void ins_compl_check_keys(int frequency, int in_compl_func);
 int get_literal(void);
diff --git a/src/testdir/test_popup.vim b/src/testdir/test_popup.vim
index 663a6a8..c69c3b0 100644
--- a/src/testdir/test_popup.vim
+++ b/src/testdir/test_popup.vim
@@ -896,4 +896,105 @@
   endtry
 endfunc
 
+func Test_popup_complete_info_01()
+  new
+  inoremap <buffer><F5> <C-R>=complete_info().mode<CR>
+  func s:complTestEval() abort
+    call complete(1, ['aa', 'ab'])
+    return ''
+  endfunc
+  inoremap <buffer><F6> <C-R>=s:complTestEval()<CR>
+  call writefile([
+        \ 'dummy	dummy.txt	1',
+        \], 'Xdummy.txt')
+  setlocal tags=Xdummy.txt
+  setlocal dictionary=Xdummy.txt
+  setlocal thesaurus=Xdummy.txt
+  setlocal omnifunc=syntaxcomplete#Complete
+  setlocal completefunc=syntaxcomplete#Complete
+  setlocal spell
+  for [keys, mode_name] in [
+        \ ["", ''],
+        \ ["\<C-X>", 'ctrl_x'],
+        \ ["\<C-X>\<C-N>", 'keyword'],
+        \ ["\<C-X>\<C-P>", 'keyword'],
+        \ ["\<C-X>\<C-L>", 'whole_line'],
+        \ ["\<C-X>\<C-F>", 'files'],
+        \ ["\<C-X>\<C-]>", 'tags'],
+        \ ["\<C-X>\<C-D>", 'path_defines'],
+        \ ["\<C-X>\<C-I>", 'path_patterns'],
+        \ ["\<C-X>\<C-K>", 'dictionary'],
+        \ ["\<C-X>\<C-T>", 'thesaurus'],
+        \ ["\<C-X>\<C-V>", 'cmdline'],
+        \ ["\<C-X>\<C-U>", 'function'],
+        \ ["\<C-X>\<C-O>", 'omni'],
+        \ ["\<C-X>s", 'spell'],
+        \ ["\<F6>", 'eval'],
+        \]
+    call feedkeys("i" . keys . "\<F5>\<Esc>", 'tx')
+    call assert_equal(mode_name, getline('.'))
+    %d
+  endfor
+  call delete('Xdummy.txt')
+  bwipe!
+endfunc
+
+func UserDefinedComplete(findstart, base)
+  if a:findstart
+    return 0
+  else
+    return [
+          \   { 'word': 'Jan', 'menu': 'January' },
+          \   { 'word': 'Feb', 'menu': 'February' },
+          \   { 'word': 'Mar', 'menu': 'March' },
+          \   { 'word': 'Apr', 'menu': 'April' },
+          \   { 'word': 'May', 'menu': 'May' },
+          \ ]
+  endif
+endfunc
+
+func GetCompleteInfo()
+  if empty(g:compl_what)
+    let g:compl_info = complete_info()
+  else
+    let g:compl_info = complete_info(g:compl_what)
+  endif
+  return ''
+endfunc
+
+func Test_popup_complete_info_02()
+  new
+  inoremap <buffer><F5> <C-R>=GetCompleteInfo()<CR>
+  setlocal completefunc=UserDefinedComplete
+
+  let d = {
+    \   'mode': 'function',
+    \   'pum_visible': 1,
+    \   'items': [
+    \     {'word': 'Jan', 'menu': 'January', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''},
+    \     {'word': 'Feb', 'menu': 'February', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''},
+    \     {'word': 'Mar', 'menu': 'March', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''},
+    \     {'word': 'Apr', 'menu': 'April', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''},
+    \     {'word': 'May', 'menu': 'May', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}
+    \   ],
+    \   'selected': 0,
+    \ }
+
+  let g:compl_what = []
+  call feedkeys("i\<C-X>\<C-U>\<F5>", 'tx')
+  call assert_equal(d, g:compl_info)
+
+  let g:compl_what = ['mode', 'pum_visible', 'selected']
+  call remove(d, 'items')
+  call feedkeys("i\<C-X>\<C-U>\<F5>", 'tx')
+  call assert_equal(d, g:compl_info)
+
+  let g:compl_what = ['mode']
+  call remove(d, 'selected')
+  call remove(d, 'pum_visible')
+  call feedkeys("i\<C-X>\<C-U>\<F5>", 'tx')
+  call assert_equal(d, g:compl_info)
+  bwipe!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index b1d79b9..ff18ac5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -776,6 +776,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1068,
+/**/
     1067,
 /**/
     1066,