Merge remote-tracking branch 'upstream/master' into usermarksusermarks

1 files changed, 1849 insertions, 1128 deletions

diff --git a/src/nvim/cmdexpand.c b/src/nvim/cmdexpand.c
index e82e98ba4e..be815151ef 100644
--- a/src/nvim/cmdexpand.c
+++ b/src/nvim/cmdexpand.c
@@ -3,9 +3,20 @@
 
 // cmdexpand.c: functions for command-line completion
 
+#include <assert.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "auto/config.h"
+#include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/arglist.h"
 #include "nvim/ascii.h"
+#include "nvim/autocmd.h"
 #include "nvim/buffer.h"
 #include "nvim/charset.h"
 #include "nvim/cmdexpand.h"
@@ -13,27 +24,42 @@
 #include "nvim/drawscreen.h"
 #include "nvim/eval.h"
 #include "nvim/eval/funcs.h"
+#include "nvim/eval/typval.h"
+#include "nvim/eval/typval_defs.h"
 #include "nvim/eval/userfunc.h"
 #include "nvim/ex_cmds.h"
-#include "nvim/ex_cmds2.h"
 #include "nvim/ex_docmd.h"
 #include "nvim/ex_getln.h"
 #include "nvim/garray.h"
 #include "nvim/getchar.h"
+#include "nvim/gettext.h"
+#include "nvim/globals.h"
+#include "nvim/grid.h"
+#include "nvim/hashtab.h"
 #include "nvim/help.h"
+#include "nvim/highlight_defs.h"
 #include "nvim/highlight_group.h"
-#include "nvim/if_cscope.h"
+#include "nvim/keycodes.h"
+#include "nvim/locale.h"
+#include "nvim/log.h"
 #include "nvim/lua/executor.h"
+#include "nvim/macros.h"
 #include "nvim/mapping.h"
+#include "nvim/mbyte.h"
+#include "nvim/memory.h"
 #include "nvim/menu.h"
+#include "nvim/message.h"
 #include "nvim/option.h"
 #include "nvim/os/os.h"
+#include "nvim/path.h"
 #include "nvim/popupmenu.h"
+#include "nvim/pos.h"
 #include "nvim/profile.h"
 #include "nvim/regexp.h"
-#include "nvim/screen.h"
+#include "nvim/runtime.h"
 #include "nvim/search.h"
 #include "nvim/sign.h"
+#include "nvim/statusline.h"
 #include "nvim/strings.h"
 #include "nvim/syntax.h"
 #include "nvim/tag.h"
@@ -47,7 +73,7 @@
 typedef char *(*CompleteListItemGetter)(expand_T *, int);
 
 /// Type used by call_user_expand_func
-typedef void *(*user_expand_func_T)(const char_u *, int, typval_T *);
+typedef void *(*user_expand_func_T)(const char *, int, typval_T *);
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "cmdexpand.c.generated.h"
@@ -63,10 +89,48 @@ static int compl_match_arraysize;
 static int compl_startcol;
 static int compl_selected;
 
+#define SHOW_MATCH(m) (showtail ? showmatches_gettail(matches[m], false) : matches[m])
+
+/// Returns true if fuzzy completion is supported for a given cmdline completion
+/// context.
+static bool cmdline_fuzzy_completion_supported(const expand_T *const xp)
+  FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL FUNC_ATTR_PURE
+{
+  return (wop_flags & WOP_FUZZY)
+         && xp->xp_context != EXPAND_BOOL_SETTINGS
+         && xp->xp_context != EXPAND_COLORS
+         && xp->xp_context != EXPAND_COMPILER
+         && xp->xp_context != EXPAND_DIRECTORIES
+         && xp->xp_context != EXPAND_FILES
+         && xp->xp_context != EXPAND_FILES_IN_PATH
+         && xp->xp_context != EXPAND_FILETYPE
+         && xp->xp_context != EXPAND_HELP
+         && xp->xp_context != EXPAND_LUA
+         && xp->xp_context != EXPAND_OLD_SETTING
+         && xp->xp_context != EXPAND_OWNSYNTAX
+         && xp->xp_context != EXPAND_PACKADD
+         && xp->xp_context != EXPAND_SHELLCMD
+         && xp->xp_context != EXPAND_TAGS
+         && xp->xp_context != EXPAND_TAGS_LISTFILES
+         && xp->xp_context != EXPAND_USER_LIST
+         && xp->xp_context != EXPAND_USER_LUA;
+}
+
+/// Returns true if fuzzy completion for cmdline completion is enabled and
+/// "fuzzystr" is not empty.  If search pattern is empty, then don't use fuzzy
+/// matching.
+bool cmdline_fuzzy_complete(const char *const fuzzystr)
+  FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL FUNC_ATTR_PURE
+{
+  return (wop_flags & WOP_FUZZY) && *fuzzystr != NUL;
+}
+
+/// Sort function for the completion matches.
+/// <SNR> functions should be sorted to the end.
 static int sort_func_compare(const void *s1, const void *s2)
 {
-  char_u *p1 = *(char_u **)s1;
-  char_u *p2 = *(char_u **)s2;
+  char *p1 = *(char **)s1;
+  char *p2 = *(char **)s2;
 
   if (*p1 != '<' && *p2 == '<') {
     return -1;
@@ -74,74 +138,79 @@ static int sort_func_compare(const void *s1, const void *s2)
   if (*p1 == '<' && *p2 != '<') {
     return 1;
   }
-  return STRCMP(p1, p2);
+  return strcmp(p1, p2);
 }
 
-static void ExpandEscape(expand_T *xp, char_u *str, int numfiles, char **files, int options)
+/// Escape special characters in the cmdline completion matches.
+static void wildescape(expand_T *xp, const char *str, int numfiles, char **files)
 {
-  int i;
-  char_u *p;
+  char *p;
   const int vse_what = xp->xp_context == EXPAND_BUFFERS ? VSE_BUFFER : VSE_NONE;
 
-  // May change home directory back to "~"
-  if (options & WILD_HOME_REPLACE) {
-    tilde_replace(str, numfiles, files);
-  }
-
-  if (options & WILD_ESCAPE) {
-    if (xp->xp_context == EXPAND_FILES
-        || xp->xp_context == EXPAND_FILES_IN_PATH
-        || xp->xp_context == EXPAND_SHELLCMD
-        || xp->xp_context == EXPAND_BUFFERS
-        || xp->xp_context == EXPAND_DIRECTORIES) {
-      // Insert a backslash into a file name before a space, \, %, #
-      // and wildmatch characters, except '~'.
-      for (i = 0; i < numfiles; i++) {
-        // for ":set path=" we need to escape spaces twice
-        if (xp->xp_backslash == XP_BS_THREE) {
-          p = vim_strsave_escaped((char_u *)files[i], (char_u *)" ");
-          xfree(files[i]);
-          files[i] = (char *)p;
+  if (xp->xp_context == EXPAND_FILES
+      || xp->xp_context == EXPAND_FILES_IN_PATH
+      || xp->xp_context == EXPAND_SHELLCMD
+      || xp->xp_context == EXPAND_BUFFERS
+      || xp->xp_context == EXPAND_DIRECTORIES) {
+    // Insert a backslash into a file name before a space, \, %, #
+    // and wildmatch characters, except '~'.
+    for (int i = 0; i < numfiles; i++) {
+      // for ":set path=" we need to escape spaces twice
+      if (xp->xp_backslash == XP_BS_THREE) {
+        p = vim_strsave_escaped(files[i], " ");
+        xfree(files[i]);
+        files[i] = p;
 #if defined(BACKSLASH_IN_FILENAME)
-          p = vim_strsave_escaped(files[i], (char_u *)" ");
-          xfree(files[i]);
-          files[i] = p;
+        p = vim_strsave_escaped(files[i], " ");
+        xfree(files[i]);
+        files[i] = p;
 #endif
-        }
+      }
 #ifdef BACKSLASH_IN_FILENAME
-        p = (char_u *)vim_strsave_fnameescape((const char *)files[i], vse_what);
+      p = vim_strsave_fnameescape(files[i], vse_what);
 #else
-        p = (char_u *)vim_strsave_fnameescape((const char *)files[i],
-                                              xp->xp_shell ? VSE_SHELL : vse_what);
+      p = vim_strsave_fnameescape(files[i], xp->xp_shell ? VSE_SHELL : vse_what);
 #endif
-        xfree(files[i]);
-        files[i] = (char *)p;
+      xfree(files[i]);
+      files[i] = p;
 
-        // If 'str' starts with "\~", replace "~" at start of
-        // files[i] with "\~".
-        if (str[0] == '\\' && str[1] == '~' && files[i][0] == '~') {
-          escape_fname(&files[i]);
-        }
+      // If 'str' starts with "\~", replace "~" at start of
+      // files[i] with "\~".
+      if (str[0] == '\\' && str[1] == '~' && files[i][0] == '~') {
+        escape_fname(&files[i]);
       }
-      xp->xp_backslash = XP_BS_NONE;
+    }
+    xp->xp_backslash = XP_BS_NONE;
 
-      // If the first file starts with a '+' escape it.  Otherwise it
-      // could be seen as "+cmd".
-      if (*files[0] == '+') {
-        escape_fname(&files[0]);
-      }
-    } else if (xp->xp_context == EXPAND_TAGS) {
-      // Insert a backslash before characters in a tag name that
-      // would terminate the ":tag" command.
-      for (i = 0; i < numfiles; i++) {
-        p = vim_strsave_escaped((char_u *)files[i], (char_u *)"\\|\"");
-        xfree(files[i]);
-        files[i] = (char *)p;
-      }
+    // If the first file starts with a '+' escape it.  Otherwise it
+    // could be seen as "+cmd".
+    if (*files[0] == '+') {
+      escape_fname(&files[0]);
+    }
+  } else if (xp->xp_context == EXPAND_TAGS) {
+    // Insert a backslash before characters in a tag name that
+    // would terminate the ":tag" command.
+    for (int i = 0; i < numfiles; i++) {
+      p = vim_strsave_escaped(files[i], "\\|\"");
+      xfree(files[i]);
+      files[i] = p;
     }
   }
 }
 
+/// Escape special characters in the cmdline completion matches.
+static void ExpandEscape(expand_T *xp, char *str, int numfiles, char **files, int options)
+{
+  // May change home directory back to "~"
+  if (options & WILD_HOME_REPLACE) {
+    tilde_replace(str, numfiles, files);
+  }
+
+  if (options & WILD_ESCAPE) {
+    wildescape(xp, str, numfiles, files);
+  }
+}
+
 /// Return FAIL if this is not an appropriate context in which to do
 /// completion of anything, return OK if it is (even if there are no matches).
 /// For the caller, this means that the character is just passed through like a
@@ -153,8 +222,8 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
 {
   CmdlineInfo *const ccline = get_cmdline_info();
   int i, j;
-  char_u *p1;
-  char_u *p2;
+  char *p1;
+  char *p2;
   int difflen;
 
   if (xp->xp_numfiles == -1) {
@@ -171,34 +240,43 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
     return FAIL;
   }
 
-  if (!(ui_has(kUICmdline) || ui_has(kUIWildmenu))) {
+  // If cmd_silent is set then don't show the dots, because redrawcmd() below
+  // won't remove them.
+  if (!cmd_silent && !(ui_has(kUICmdline) || ui_has(kUIWildmenu))) {
     msg_puts("...");  // show that we are busy
     ui_flush();
   }
 
-  i = (int)((char_u *)xp->xp_pattern - ccline->cmdbuff);
+  i = (int)(xp->xp_pattern - ccline->cmdbuff);
   assert(ccline->cmdpos >= i);
   xp->xp_pattern_len = (size_t)ccline->cmdpos - (size_t)i;
 
-  if (type == WILD_NEXT || type == WILD_PREV) {
+  if (type == WILD_NEXT || type == WILD_PREV
+      || type == WILD_PAGEUP || type == WILD_PAGEDOWN
+      || type == WILD_PUM_WANT) {
     // Get next/previous match for a previous expanded pattern.
     p2 = ExpandOne(xp, NULL, NULL, 0, type);
   } else {
+    if (cmdline_fuzzy_completion_supported(xp)) {
+      // If fuzzy matching, don't modify the search string
+      p1 = xstrdup(xp->xp_pattern);
+    } else {
+      p1 = addstar(xp->xp_pattern, xp->xp_pattern_len, xp->xp_context);
+    }
     // Translate string into pattern and expand it.
-    p1 = addstar((char_u *)xp->xp_pattern, xp->xp_pattern_len, xp->xp_context);
     const int use_options = (options
                              | WILD_HOME_REPLACE
                              | WILD_ADD_SLASH
                              | WILD_SILENT
                              | (escape ? WILD_ESCAPE : 0)
                              | (p_wic ? WILD_ICASE : 0));
-    p2 = ExpandOne(xp, p1, vim_strnsave(&ccline->cmdbuff[i], xp->xp_pattern_len),
+    p2 = ExpandOne(xp, p1, xstrnsave(&ccline->cmdbuff[i], xp->xp_pattern_len),
                    use_options, type);
     xfree(p1);
 
     // xp->xp_pattern might have been modified by ExpandOne (for example,
     // in lua completion), so recompute the pattern index and length
-    i = (int)((char_u *)xp->xp_pattern - ccline->cmdbuff);
+    i = (int)(xp->xp_pattern - ccline->cmdbuff);
     xp->xp_pattern_len = (size_t)ccline->cmdpos - (size_t)i;
 
     // Longest match: make sure it is not shorter, happens with :help.
@@ -209,23 +287,23 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
           break;
         }
       }
-      if ((int)STRLEN(p2) < j) {
+      if ((int)strlen(p2) < j) {
         XFREE_CLEAR(p2);
       }
     }
   }
 
   if (p2 != NULL && !got_int) {
-    difflen = (int)STRLEN(p2) - (int)(xp->xp_pattern_len);
+    difflen = (int)strlen(p2) - (int)(xp->xp_pattern_len);
     if (ccline->cmdlen + difflen + 4 > ccline->cmdbufflen) {
       realloc_cmdbuff(ccline->cmdlen + difflen + 4);
-      xp->xp_pattern = (char *)ccline->cmdbuff + i;
+      xp->xp_pattern = ccline->cmdbuff + i;
     }
     assert(ccline->cmdpos <= ccline->cmdlen);
     memmove(&ccline->cmdbuff[ccline->cmdpos + difflen],
             &ccline->cmdbuff[ccline->cmdpos],
             (size_t)ccline->cmdlen - (size_t)ccline->cmdpos + 1);
-    memmove(&ccline->cmdbuff[i], p2, STRLEN(p2));
+    memmove(&ccline->cmdbuff[i], p2, strlen(p2));
     ccline->cmdlen += difflen;
     ccline->cmdpos += difflen;
   }
@@ -250,19 +328,54 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
   return OK;
 }
 
+/// Create and display a cmdline completion popup menu with items from
+/// "matches".
+static int cmdline_pum_create(CmdlineInfo *ccline, expand_T *xp, char **matches, int numMatches,
+                              int showtail)
+{
+  assert(numMatches >= 0);
+  // Add all the completion matches
+  compl_match_arraysize = numMatches;
+  compl_match_array = xmalloc(sizeof(pumitem_T) * (size_t)compl_match_arraysize);
+  for (int i = 0; i < numMatches; i++) {
+    compl_match_array[i] = (pumitem_T){
+      .pum_text = SHOW_MATCH(i),
+      .pum_info = NULL,
+      .pum_extra = NULL,
+      .pum_kind = NULL,
+    };
+  }
+
+  // Compute the popup menu starting column
+  char *endpos = showtail ? showmatches_gettail(xp->xp_pattern, true) : xp->xp_pattern;
+  if (ui_has(kUICmdline)) {
+    compl_startcol = (int)(endpos - ccline->cmdbuff);
+  } else {
+    compl_startcol = cmd_screencol((int)(endpos - ccline->cmdbuff));
+  }
+
+  // no default selection
+  compl_selected = -1;
+
+  cmdline_pum_display(true);
+
+  return EXPAND_OK;
+}
+
 void cmdline_pum_display(bool changed_array)
 {
   pum_display(compl_match_array, compl_match_arraysize, compl_selected,
               changed_array, compl_startcol);
 }
 
+/// Returns true if the cmdline completion popup menu is being displayed.
 bool cmdline_pum_active(void)
 {
   // compl_match_array != NULL should already imply pum_visible() in Nvim.
   return compl_match_array != NULL;
 }
 
-/// Remove the cmdline completion popup menu
+/// Remove the cmdline completion popup menu (if present), free the list of items.
 void cmdline_pum_remove(void)
 {
   pum_undisplay(true);
@@ -275,7 +388,420 @@ void cmdline_pum_cleanup(CmdlineInfo *cclp)
   wildmenu_cleanup(cclp);
 }
 
-/// Do wildcard expansion on the string 'str'.
+/// Return the number of characters that should be skipped in the wildmenu
+/// These are backslashes used for escaping.  Do show backslashes in help tags.
+static int skip_wildmenu_char(expand_T *xp, char *s)
+{
+  if ((rem_backslash(s) && xp->xp_context != EXPAND_HELP)
+      || ((xp->xp_context == EXPAND_MENUS || xp->xp_context == EXPAND_MENUNAMES)
+          && (s[0] == '\t' || (s[0] == '\\' && s[1] != NUL)))) {
+#ifndef BACKSLASH_IN_FILENAME
+    // TODO(bfredl): Why in the actual fuck are we special casing the
+    // shell variety deep in the redraw logic? Shell special snowflakiness
+    // should already be eliminated multiple layers before reaching the
+    // screen infracstructure.
+    if (xp->xp_shell && csh_like_shell() && s[1] == '\\' && s[2] == '!') {
+      return 2;
+    }
+#endif
+    return 1;
+  }
+  return 0;
+}
+
+/// Get the length of an item as it will be shown in the status line.
+static int wildmenu_match_len(expand_T *xp, char *s)
+{
+  int len = 0;
+
+  int emenu = (xp->xp_context == EXPAND_MENUS
+               || xp->xp_context == EXPAND_MENUNAMES);
+
+  // Check for menu separators - replace with '|'.
+  if (emenu && menu_is_separator(s)) {
+    return 1;
+  }
+
+  while (*s != NUL) {
+    s += skip_wildmenu_char(xp, s);
+    len += ptr2cells(s);
+    MB_PTR_ADV(s);
+  }
+
+  return len;
+}
+
+/// Show wildchar matches in the status line.
+/// Show at least the "match" item.
+/// We start at item "first_match" in the list and show all matches that fit.
+///
+/// If inversion is possible we use it. Else '=' characters are used.
+///
+/// @param matches  list of matches
+static void redraw_wildmenu(expand_T *xp, int num_matches, char **matches, int match, int showtail)
+{
+  int row;
+  char *buf;
+  int len;
+  int clen;                     // length in screen cells
+  int fillchar;
+  int attr;
+  int i;
+  bool highlight = true;
+  char *selstart = NULL;
+  int selstart_col = 0;
+  char *selend = NULL;
+  static int first_match = 0;
+  bool add_left = false;
+  char *s;
+  int emenu;
+  int l;
+
+  if (matches == NULL) {        // interrupted completion?
+    return;
+  }
+
+  buf = xmalloc((size_t)Columns * MB_MAXBYTES + 1);
+
+  if (match == -1) {    // don't show match but original text
+    match = 0;
+    highlight = false;
+  }
+  // count 1 for the ending ">"
+  clen = wildmenu_match_len(xp, SHOW_MATCH(match)) + 3;
+  if (match == 0) {
+    first_match = 0;
+  } else if (match < first_match) {
+    // jumping left, as far as we can go
+    first_match = match;
+    add_left = true;
+  } else {
+    // check if match fits on the screen
+    for (i = first_match; i < match; i++) {
+      clen += wildmenu_match_len(xp, SHOW_MATCH(i)) + 2;
+    }
+    if (first_match > 0) {
+      clen += 2;
+    }
+    // jumping right, put match at the left
+    if ((long)clen > Columns) {
+      first_match = match;
+      // if showing the last match, we can add some on the left
+      clen = 2;
+      for (i = match; i < num_matches; i++) {
+        clen += wildmenu_match_len(xp, SHOW_MATCH(i)) + 2;
+        if ((long)clen >= Columns) {
+          break;
+        }
+      }
+      if (i == num_matches) {
+        add_left = true;
+      }
+    }
+  }
+  if (add_left) {
+    while (first_match > 0) {
+      clen += wildmenu_match_len(xp, SHOW_MATCH(first_match - 1)) + 2;
+      if ((long)clen >= Columns) {
+        break;
+      }
+      first_match--;
+    }
+  }
+
+  fillchar = fillchar_status(&attr, curwin);
+
+  if (first_match == 0) {
+    *buf = NUL;
+    len = 0;
+  } else {
+    STRCPY(buf, "< ");
+    len = 2;
+  }
+  clen = len;
+
+  i = first_match;
+  while (clen + wildmenu_match_len(xp, SHOW_MATCH(i)) + 2 < Columns) {
+    if (i == match) {
+      selstart = buf + len;
+      selstart_col = clen;
+    }
+
+    s = SHOW_MATCH(i);
+    // Check for menu separators - replace with '|'
+    emenu = (xp->xp_context == EXPAND_MENUS
+             || xp->xp_context == EXPAND_MENUNAMES);
+    if (emenu && menu_is_separator(s)) {
+      STRCPY(buf + len, transchar('|'));
+      l = (int)strlen(buf + len);
+      len += l;
+      clen += l;
+    } else {
+      for (; *s != NUL; s++) {
+        s += skip_wildmenu_char(xp, s);
+        clen += ptr2cells(s);
+        if ((l = utfc_ptr2len(s)) > 1) {
+          strncpy(buf + len, s, (size_t)l);  // NOLINT(runtime/printf)
+          s += l - 1;
+          len += l;
+        } else {
+          STRCPY(buf + len, transchar_byte((uint8_t)(*s)));
+          len += (int)strlen(buf + len);
+        }
+      }
+    }
+    if (i == match) {
+      selend = buf + len;
+    }
+
+    *(buf + len++) = ' ';
+    *(buf + len++) = ' ';
+    clen += 2;
+    if (++i == num_matches) {
+      break;
+    }
+  }
+
+  if (i != num_matches) {
+    *(buf + len++) = '>';
+    clen++;
+  }
+
+  buf[len] = NUL;
+
+  row = cmdline_row - 1;
+  if (row >= 0) {
+    if (wild_menu_showing == 0 || wild_menu_showing == WM_LIST) {
+      if (msg_scrolled > 0) {
+        // Put the wildmenu just above the command line.  If there is
+        // no room, scroll the screen one line up.
+        if (cmdline_row == Rows - 1) {
+          msg_scroll_up(false, false);
+          msg_scrolled++;
+        } else {
+          cmdline_row++;
+          row++;
+        }
+        wild_menu_showing = WM_SCROLLED;
+      } else {
+        // Create status line if needed by setting 'laststatus' to 2.
+        // Set 'winminheight' to zero to avoid that the window is
+        // resized.
+        if (lastwin->w_status_height == 0 && global_stl_height() == 0) {
+          save_p_ls = (int)p_ls;
+          save_p_wmh = (int)p_wmh;
+          p_ls = 2;
+          p_wmh = 0;
+          last_status(false);
+        }
+        wild_menu_showing = WM_SHOWN;
+      }
+    }
+
+    // Tricky: wildmenu can be drawn either over a status line, or at empty
+    // scrolled space in the message output
+    ScreenGrid *grid = (wild_menu_showing == WM_SCROLLED)
+                        ? &msg_grid_adj : &default_grid;
+
+    grid_puts(grid, buf, row, 0, attr);
+    if (selstart != NULL && highlight) {
+      *selend = NUL;
+      grid_puts(grid, selstart, row, selstart_col, HL_ATTR(HLF_WM));
+    }
+
+    grid_fill(grid, row, row + 1, clen, Columns,
+              fillchar, fillchar, attr);
+  }
+
+  win_redraw_last_status(topframe);
+  xfree(buf);
+}
+
+/// Get the next or prev cmdline completion match. The index of the match is set
+/// in "p_findex"
+static char *get_next_or_prev_match(int mode, expand_T *xp, int *p_findex, char *orig_save)
+{
+  if (xp->xp_numfiles <= 0) {
+    return NULL;
+  }
+
+  int findex = *p_findex;
+
+  if (mode == WILD_PREV) {
+    if (findex == -1) {
+      findex = xp->xp_numfiles;
+    }
+    findex--;
+  } else if (mode == WILD_NEXT) {
+    findex++;
+  } else if (mode == WILD_PAGEUP) {
+    if (findex == 0) {
+      // at the first entry, don't select any entries
+      findex = -1;
+    } else if (findex == -1) {
+      // no entry is selected. select the last entry
+      findex = xp->xp_numfiles - 1;
+    } else {
+      // go up by the pum height
+      int ht = pum_get_height();
+      if (ht > 3) {
+        ht -= 2;
+      }
+      findex -= ht;
+      if (findex < 0) {
+        // few entries left, select the first entry
+        findex = 0;
+      }
+    }
+  } else if (mode == WILD_PAGEDOWN) {
+    if (findex == xp->xp_numfiles - 1) {
+      // at the last entry, don't select any entries
+      findex = -1;
+    } else if (findex == -1) {
+      // no entry is selected. select the first entry
+      findex = 0;
+    } else {
+      // go down by the pum height
+      int ht = pum_get_height();
+      if (ht > 3) {
+        ht -= 2;
+      }
+      findex += ht;
+      if (findex >= xp->xp_numfiles) {
+        // few entries left, select the last entry
+        findex = xp->xp_numfiles - 1;
+      }
+    }
+  } else {  // mode == WILD_PUM_WANT
+    assert(pum_want.active);
+    findex = pum_want.item;
+  }
+
+  // When wrapping around, return the original string, set findex to -1.
+  if (findex < 0) {
+    if (orig_save == NULL) {
+      findex = xp->xp_numfiles - 1;
+    } else {
+      findex = -1;
+    }
+  }
+  if (findex >= xp->xp_numfiles) {
+    if (orig_save == NULL) {
+      findex = 0;
+    } else {
+      findex = -1;
+    }
+  }
+  if (compl_match_array) {
+    compl_selected = findex;
+    cmdline_pum_display(false);
+  } else if (p_wmnu) {
+    redraw_wildmenu(xp, xp->xp_numfiles, xp->xp_files, findex, cmd_showtail);
+  }
+  *p_findex = findex;
+
+  return xstrdup(findex == -1 ? orig_save : xp->xp_files[findex]);
+}
+
+/// Start the command-line expansion and get the matches.
+static char *ExpandOne_start(int mode, expand_T *xp, char *str, int options)
+{
+  int non_suf_match;  // number without matching suffix
+  char *ss = NULL;
+
+  // Do the expansion.
+  if (ExpandFromContext(xp, str, &xp->xp_files, &xp->xp_numfiles, options) == FAIL) {
+#ifdef FNAME_ILLEGAL
+    // Illegal file name has been silently skipped.  But when there
+    // are wildcards, the real problem is that there was no match,
+    // causing the pattern to be added, which has illegal characters.
+    if (!(options & WILD_SILENT) && (options & WILD_LIST_NOTFOUND)) {
+      semsg(_(e_nomatch2), str);
+    }
+#endif
+  } else if (xp->xp_numfiles == 0) {
+    if (!(options & WILD_SILENT)) {
+      semsg(_(e_nomatch2), str);
+    }
+  } else {
+    // Escape the matches for use on the command line.
+    ExpandEscape(xp, str, xp->xp_numfiles, xp->xp_files, options);
+
+    // Check for matching suffixes in file names.
+    if (mode != WILD_ALL && mode != WILD_ALL_KEEP && mode != WILD_LONGEST) {
+      if (xp->xp_numfiles) {
+        non_suf_match = xp->xp_numfiles;
+      } else {
+        non_suf_match = 1;
+      }
+      if ((xp->xp_context == EXPAND_FILES
+           || xp->xp_context == EXPAND_DIRECTORIES)
+          && xp->xp_numfiles > 1) {
+        // More than one match; check suffix.
+        // The files will have been sorted on matching suffix in
+        // expand_wildcards, only need to check the first two.
+        non_suf_match = 0;
+        for (int i = 0; i < 2; i++) {
+          if (match_suffix(xp->xp_files[i])) {
+            non_suf_match++;
+          }
+        }
+      }
+      if (non_suf_match != 1) {
+        // Can we ever get here unless it's while expanding
+        // interactively?  If not, we can get rid of this all
+        // together. Don't really want to wait for this message
+        // (and possibly have to hit return to continue!).
+        if (!(options & WILD_SILENT)) {
+          emsg(_(e_toomany));
+        } else if (!(options & WILD_NO_BEEP)) {
+          beep_flush();
+        }
+      }
+      if (!(non_suf_match != 1 && mode == WILD_EXPAND_FREE)) {
+        ss = xstrdup(xp->xp_files[0]);
+      }
+    }
+  }
+
+  return ss;
+}
+
+/// Return the longest common part in the list of cmdline completion matches.
+static char *find_longest_match(expand_T *xp, int options)
+{
+  size_t len = 0;
+
+  for (size_t mb_len; xp->xp_files[0][len]; len += mb_len) {
+    mb_len = (size_t)utfc_ptr2len(&xp->xp_files[0][len]);
+    int c0 = utf_ptr2char(&xp->xp_files[0][len]);
+    int i;
+    for (i = 1; i < xp->xp_numfiles; i++) {
+      int ci = utf_ptr2char(&xp->xp_files[i][len]);
+
+      if (p_fic && (xp->xp_context == EXPAND_DIRECTORIES
+                    || xp->xp_context == EXPAND_FILES
+                    || xp->xp_context == EXPAND_SHELLCMD
+                    || xp->xp_context == EXPAND_BUFFERS)) {
+        if (mb_tolower(c0) != mb_tolower(ci)) {
+          break;
+        }
+      } else if (c0 != ci) {
+        break;
+      }
+    }
+    if (i < xp->xp_numfiles) {
+      if (!(options & WILD_NO_BEEP)) {
+        vim_beep(BO_WILD);
+      }
+      break;
+    }
+  }
+
+  return xstrndup(xp->xp_files[0], len);
+}
+
+/// Do wildcard expansion on the string "str".
 /// Chars that should not be expanded must be preceded with a backslash.
 /// Return a pointer to allocated memory containing the new string.
 /// Return NULL for failure.
@@ -295,6 +821,11 @@ void cmdline_pum_cleanup(CmdlineInfo *cclp)
 /// mode = WILD_ALL:         return all matches concatenated
 /// mode = WILD_LONGEST:     return longest matched part
 /// mode = WILD_ALL_KEEP:    get all matches, keep matches
+/// mode = WILD_APPLY:       apply the item selected in the cmdline completion
+///                          popup menu and close the menu.
+/// mode = WILD_CANCEL:      cancel and close the cmdline completion popup and
+///                          use the original text.
+/// mode = WILD_PUM_WANT:    use the match at index pum_want.item
 ///
 /// options = WILD_LIST_NOTFOUND:    list entries without a match
 /// options = WILD_HOME_REPLACE:     do home_replace() for buffer names
@@ -309,63 +840,27 @@ void cmdline_pum_cleanup(CmdlineInfo *cclp)
 /// The variables xp->xp_context and xp->xp_backslash must have been set!
 ///
 /// @param orig  allocated copy of original of expanded string
-char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode)
+char *ExpandOne(expand_T *xp, char *str, char *orig, int options, int mode)
 {
-  char_u *ss = NULL;
+  char *ss = NULL;
   static int findex;
-  static char_u *orig_save = NULL;      // kept value of orig
+  static char *orig_save = NULL;      // kept value of orig
   int orig_saved = false;
   int i;
-  int non_suf_match;                    // number without matching suffix
 
   // first handle the case of using an old match
-  if (mode == WILD_NEXT || mode == WILD_PREV) {
-    if (xp->xp_numfiles > 0) {
-      if (mode == WILD_PREV) {
-        if (findex == -1) {
-          findex = xp->xp_numfiles;
-        }
-        findex--;
-      } else {  // mode == WILD_NEXT
-        findex++;
-      }
-
-      // When wrapping around, return the original string, set findex to
-      // -1.
-      if (findex < 0) {
-        if (orig_save == NULL) {
-          findex = xp->xp_numfiles - 1;
-        } else {
-          findex = -1;
-        }
-      }
-      if (findex >= xp->xp_numfiles) {
-        if (orig_save == NULL) {
-          findex = 0;
-        } else {
-          findex = -1;
-        }
-      }
-      if (compl_match_array) {
-        compl_selected = findex;
-        cmdline_pum_display(false);
-      } else if (p_wmnu) {
-        redraw_wildmenu(xp, xp->xp_numfiles, xp->xp_files, findex, cmd_showtail);
-      }
-      if (findex == -1) {
-        return vim_strsave(orig_save);
-      }
-      return vim_strsave((char_u *)xp->xp_files[findex]);
-    } else {
-      return NULL;
-    }
+  if (mode == WILD_NEXT || mode == WILD_PREV
+      || mode == WILD_PAGEUP || mode == WILD_PAGEDOWN
+      || mode == WILD_PUM_WANT) {
+    return get_next_or_prev_match(mode, xp, &findex, orig_save);
   }
 
   if (mode == WILD_CANCEL) {
-    ss = vim_strsave(orig_save ? orig_save : (char_u *)"");
+    ss = xstrdup(orig_save ? orig_save : "");
   } else if (mode == WILD_APPLY) {
-    ss =  vim_strsave(findex == -1 ? (orig_save ? orig_save : (char_u *)"") :
-                      (char_u *)xp->xp_files[findex]);
+    ss = xstrdup(findex == -1
+                 ? (orig_save ? orig_save : "")
+                 : xp->xp_files[findex]);
   }
 
   // free old names
@@ -373,6 +868,11 @@ char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode
     FreeWild(xp->xp_numfiles, xp->xp_files);
     xp->xp_numfiles = -1;
     XFREE_CLEAR(orig_save);
+
+    // The entries from xp_files may be used in the PUM, remove it.
+    if (compl_match_array != NULL) {
+      cmdline_pum_remove();
+    }
   }
   findex = 0;
 
@@ -385,93 +885,12 @@ char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode
     orig_save = orig;
     orig_saved = true;
 
-    // Do the expansion.
-    if (ExpandFromContext(xp, str, &xp->xp_numfiles, &xp->xp_files, options) == FAIL) {
-#ifdef FNAME_ILLEGAL
-      // Illegal file name has been silently skipped.  But when there
-      // are wildcards, the real problem is that there was no match,
-      // causing the pattern to be added, which has illegal characters.
-      if (!(options & WILD_SILENT) && (options & WILD_LIST_NOTFOUND)) {
-        semsg(_(e_nomatch2), str);
-      }
-#endif
-    } else if (xp->xp_numfiles == 0) {
-      if (!(options & WILD_SILENT)) {
-        semsg(_(e_nomatch2), str);
-      }
-    } else {
-      // Escape the matches for use on the command line.
-      ExpandEscape(xp, str, xp->xp_numfiles, xp->xp_files, options);
-
-      // Check for matching suffixes in file names.
-      if (mode != WILD_ALL && mode != WILD_ALL_KEEP
-          && mode != WILD_LONGEST) {
-        if (xp->xp_numfiles) {
-          non_suf_match = xp->xp_numfiles;
-        } else {
-          non_suf_match = 1;
-        }
-        if ((xp->xp_context == EXPAND_FILES
-             || xp->xp_context == EXPAND_DIRECTORIES)
-            && xp->xp_numfiles > 1) {
-          // More than one match; check suffix.
-          // The files will have been sorted on matching suffix in
-          // expand_wildcards, only need to check the first two.
-          non_suf_match = 0;
-          for (i = 0; i < 2; i++) {
-            if (match_suffix((char_u *)xp->xp_files[i])) {
-              non_suf_match++;
-            }
-          }
-        }
-        if (non_suf_match != 1) {
-          // Can we ever get here unless it's while expanding
-          // interactively?  If not, we can get rid of this all
-          // together. Don't really want to wait for this message
-          // (and possibly have to hit return to continue!).
-          if (!(options & WILD_SILENT)) {
-            emsg(_(e_toomany));
-          } else if (!(options & WILD_NO_BEEP)) {
-            beep_flush();
-          }
-        }
-        if (!(non_suf_match != 1 && mode == WILD_EXPAND_FREE)) {
-          ss = vim_strsave((char_u *)xp->xp_files[0]);
-        }
-      }
-    }
+    ss = ExpandOne_start(mode, xp, str, options);
   }
 
   // Find longest common part
   if (mode == WILD_LONGEST && xp->xp_numfiles > 0) {
-    size_t len = 0;
-
-    for (size_t mb_len; xp->xp_files[0][len]; len += mb_len) {
-      mb_len = (size_t)utfc_ptr2len(&xp->xp_files[0][len]);
-      int c0 = utf_ptr2char(&xp->xp_files[0][len]);
-      for (i = 1; i < xp->xp_numfiles; i++) {
-        int ci = utf_ptr2char(&xp->xp_files[i][len]);
-
-        if (p_fic && (xp->xp_context == EXPAND_DIRECTORIES
-                      || xp->xp_context == EXPAND_FILES
-                      || xp->xp_context == EXPAND_SHELLCMD
-                      || xp->xp_context == EXPAND_BUFFERS)) {
-          if (mb_tolower(c0) != mb_tolower(ci)) {
-            break;
-          }
-        } else if (c0 != ci) {
-          break;
-        }
-      }
-      if (i < xp->xp_numfiles) {
-        if (!(options & WILD_NO_BEEP)) {
-          vim_beep(BO_WILD);
-        }
-        break;
-      }
-    }
-
-    ss = (char_u *)xstrndup(xp->xp_files[0], len);
+    ss = find_longest_match(xp, options);
     findex = -1;  // next p_wc gets first one
   }
 
@@ -481,7 +900,7 @@ char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode
   if (mode == WILD_ALL && xp->xp_numfiles > 0 && !got_int) {
     size_t len = 0;
     for (i = 0; i < xp->