vim-patch:8.2.4617: no completion for :scriptnames

Problem:    No completion for :scriptnames.
Solution:   Implement :scriptnames completion. (Yegappan Lakshmanan,
            closes vim/vim#10005)

https://github.com/vim/vim/commit/454ce6737cadb82886f1fc0eb9e8666cc59ae42b

Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>

7 files changed, 92 insertions, 19 deletions

diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index bdbd026a09..ca4518d1cc 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -2983,6 +2983,7 @@ getcompletion({pat}, {type} [, {filtered}])		*getcompletion()*
 		messages	|:messages| suboptions
 		option		options
 		packadd		optional package |pack-add| names
+		scriptnames	sourced script names |:scriptnames|
 		shellcmd	Shell command
 		sign		|:sign| suboptions
 		syntax		syntax file names |'syntax'|
@@ -3002,7 +3003,10 @@ getcompletion({pat}, {type} [, {filtered}])		*getcompletion()*
 
 		If the 'wildoptions' option contains "fuzzy", then fuzzy
 		matching is used to get the completion matches. Otherwise
-		regular expression matching is used.
+		regular expression matching is used.  Thus this function
+		follows the user preference, what happens on the command line.
+		If you do not want this you can make 'wildoptions' empty
+		before calling getcompletion() and restore it afterwards.
 
 		If {type} is "cmdline", then the |cmdline-completion| result is
 		returned.  For example, to complete the possible values after
diff --git a/src/nvim/cmdexpand.c b/src/nvim/cmdexpand.c
index 4f6936958f..b5956d75ab 100644
--- a/src/nvim/cmdexpand.c
+++ b/src/nvim/cmdexpand.c
@@ -1760,6 +1760,22 @@ static const char *set_context_in_breakadd_cmd(expand_T *xp, const char *arg, cm
   return NULL;
 }
 
+static const char *set_context_in_scriptnames_cmd(expand_T *xp, const char *arg)
+{
+  xp->xp_context = EXPAND_NOTHING;
+  xp->xp_pattern = NULL;
+
+  char *p = skipwhite(arg);
+  if (ascii_isdigit(*p)) {
+    return NULL;
+  }
+
+  xp->xp_context = EXPAND_SCRIPTNAMES;
+  xp->xp_pattern = p;
+
+  return NULL;
+}
+
 /// Set the completion context in "xp" for command "cmd" with index "cmdidx".
 /// The argument to the command is "arg" and the argument flags is "argt".
 /// For user-defined commands and for environment variables, "context" has the
@@ -2119,6 +2135,9 @@ static const char *set_context_by_cmdname(const char *cmd, cmdidx_T cmdidx, expa
   case CMD_breakdel:
     return set_context_in_breakadd_cmd(xp, arg, cmdidx);
 
+  case CMD_scriptnames:
+    return set_context_in_scriptnames_cmd(xp, arg);
+
   case CMD_lua:
     xp->xp_context = EXPAND_LUA;
     break;
@@ -2496,6 +2515,19 @@ static char *get_breakadd_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
   return NULL;
 }
 
+/// Function given to ExpandGeneric() to obtain the possible arguments for the
+/// ":scriptnames" command.
+static char *get_scriptnames_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
+{
+  if (!SCRIPT_ID_VALID(idx + 1)) {
+    return NULL;
+  }
+
+  scriptitem_T *si = &SCRIPT_ITEM(idx + 1);
+  home_replace(NULL, si->sn_name, NameBuff, MAXPATHL, true);
+  return NameBuff;
+}
+
 /// Function given to ExpandGeneric() to obtain the possible arguments of the
 /// ":messages {clear}" command.
 static char *get_messages_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
@@ -2581,6 +2613,7 @@ static int ExpandOther(char *pat, expand_T *xp, regmatch_T *rmp, char ***matches
     { EXPAND_USER, get_users, true, false },
     { EXPAND_ARGLIST, get_arglist_name, true, false },
     { EXPAND_BREAKPOINT, get_breakadd_arg, true, true },
+    { EXPAND_SCRIPTNAMES, get_scriptnames_arg, true, false },
     { EXPAND_CHECKHEALTH, get_healthcheck_names, true, false },
   };
   int ret = FAIL;
@@ -2823,11 +2856,22 @@ static void ExpandGeneric(const char *const pat, expand_T *xp, regmatch_T *regma
     return;
   }
 
-  // Sort the results.  Keep menu's in the specified order.
-  if (!fuzzy && xp->xp_context != EXPAND_MENUNAMES && xp->xp_context != EXPAND_MENUS) {
-    if (xp->xp_context == EXPAND_EXPRESSION
-        || xp->xp_context == EXPAND_FUNCTIONS
-        || xp->xp_context == EXPAND_USER_FUNC) {
+  // Sort the matches when using regular expression matching and sorting
+  // applies to the completion context. Menus and scriptnames should be kept
+  // in the specified order.
+  const bool sort_matches = !fuzzy
+                            && xp->xp_context != EXPAND_MENUNAMES
+                            && xp->xp_context != EXPAND_MENUS
+                            && xp->xp_context != EXPAND_SCRIPTNAMES;
+
+  // <SNR> functions should be sorted to the end.
+  const bool funcsort = xp->xp_context == EXPAND_EXPRESSION
+                        || xp->xp_context == EXPAND_FUNCTIONS
+                        || xp->xp_context == EXPAND_USER_FUNC;
+
+  // Sort the matches.
+  if (sort_matches) {
+    if (funcsort) {
       // <SNR> functions should be sorted to the end.
       qsort(ga.ga_data, (size_t)ga.ga_len, sizeof(char *), sort_func_compare);
     } else {
@@ -2839,15 +2883,6 @@ static void ExpandGeneric(const char *const pat, expand_T *xp, regmatch_T *regma
     *matches = ga.ga_data;
     *numMatches = ga.ga_len;
   } else {
-    bool funcsort = false;
-
-    if (xp->xp_context == EXPAND_EXPRESSION
-        || xp->xp_context == EXPAND_FUNCTIONS
-        || xp->xp_context == EXPAND_USER_FUNC) {
-      // <SNR> functions should be sorted to the end.
-      funcsort = true;
-    }
-
     fuzzymatches_to_strmatches(ga.ga_data, matches, ga.ga_len, funcsort);
     *numMatches = ga.ga_len;
   }
diff --git a/src/nvim/ex_cmds.lua b/src/nvim/ex_cmds.lua
index 68db03bd7d..c8b6ceab69 100644
--- a/src/nvim/ex_cmds.lua
+++ b/src/nvim/ex_cmds.lua
@@ -2387,7 +2387,7 @@ module.cmds = {
   },
   {
     command='scriptnames',
-    flags=bit.bor(BANG, RANGE, COUNT, TRLBAR, CMDWIN, LOCK_OK),
+    flags=bit.bor(BANG, FILES, RANGE, COUNT, TRLBAR, CMDWIN, LOCK_OK),
     addr_type='ADDR_OTHER',
     func='ex_scriptnames',
   },
diff --git a/src/nvim/runtime.c b/src/nvim/runtime.c
index ea975042ed..321023bce2 100644
--- a/src/nvim/runtime.c
+++ b/src/nvim/runtime.c
@@ -2160,12 +2160,17 @@ scriptitem_T *get_current_script_id(char **fnamep, sctx_T *ret_sctx)
 /// ":scriptnames"
 void ex_scriptnames(exarg_T *eap)
 {
-  if (eap->addr_count > 0) {
+  if (eap->addr_count > 0 || *eap->arg != NUL) {
     // :script {scriptId}: edit the script
-    if (eap->line2 < 1 || eap->line2 > script_items.ga_len) {
+    if (eap->addr_count > 0 && !SCRIPT_ID_VALID(eap->line2)) {
       emsg(_(e_invarg));
     } else {
-      eap->arg = SCRIPT_ITEM(eap->line2).sn_name;
+      if (eap->addr_count > 0) {
+        eap->arg = SCRIPT_ITEM(eap->line2).sn_name;
+      } else {
+        expand_env(eap->arg, NameBuff, MAXPATHL);
+        eap->arg = NameBuff;
+      }
       do_exedit(eap, NULL);
     }
     return;
diff --git a/src/nvim/testdir/test_cmdline.vim b/src/nvim/testdir/test_cmdline.vim
index ea7bfae639..ebcbc8177e 100644
--- a/src/nvim/testdir/test_cmdline.vim
+++ b/src/nvim/testdir/test_cmdline.vim
@@ -3378,6 +3378,33 @@ func Test_cmdline_complete_breakdel()
   call assert_equal("\"breakdel here ", @:)
 endfunc
 
+" Test for :scriptnames argument completion
+func Test_cmdline_complete_scriptnames()
+  set wildmenu
+  call writefile(['let a = 1'], 'Xa1b2c3.vim')
+  source Xa1b2c3.vim
+  call feedkeys(":script \<Tab>\<Left>\<Left>\<C-B>\"\<CR>", 'tx')
+  call assert_match("\"script .*Xa1b2c3.vim$", @:)
+  call feedkeys(":script    \<Tab>\<Left>\<Left>\<C-B>\"\<CR>", 'tx')
+  call assert_match("\"script .*Xa1b2c3.vim$", @:)
+  call feedkeys(":script b2c3\<Tab>\<C-B>\"\<CR>", 'tx')
+  call assert_equal("\"script b2c3", @:)
+  call feedkeys(":script 2\<Tab>\<C-B>\"\<CR>", 'tx')
+  call assert_match("\"script 2\<Tab>$", @:)
+  call feedkeys(":script \<Tab>\<Left>\<Left> \<Tab>\<C-B>\"\<CR>", 'tx')
+  call assert_match("\"script .*Xa1b2c3.vim $", @:)
+  call feedkeys(":script \<Tab>\<Left>\<C-B>\"\<CR>", 'tx')
+  call assert_equal("\"script ", @:)
+  call assert_match('Xa1b2c3.vim$', getcompletion('.*Xa1b2.*', 'scriptnames')[0])
+  call assert_equal([], getcompletion('Xa1b2', 'scriptnames'))
+  new
+  call feedkeys(":script \<Tab>\<Left>\<Left>\<CR>", 'tx')
+  call assert_equal('Xa1b2c3.vim', fnamemodify(@%, ':t'))
+  bw!
+  call delete('Xa1b2c3.vim')
+  set wildmenu&
+endfunc
+
 " this was going over the end of IObuff
 func Test_report_error_with_composing()
   let caught = 'no'
diff --git a/src/nvim/usercmd.c b/src/nvim/usercmd.c
index 22e092781c..9c4fdd4ead 100644
--- a/src/nvim/usercmd.c
+++ b/src/nvim/usercmd.c
@@ -96,6 +96,7 @@ static const char *command_complete[] = {
   [EXPAND_USER] = "user",
   [EXPAND_USER_VARS] = "var",
   [EXPAND_BREAKPOINT] = "breakpoint",
+  [EXPAND_SCRIPTNAMES] = "scriptnames",
 };
 
 /// List of names of address types.  Must be alphabetical for completion.
diff --git a/src/nvim/vim.h b/src/nvim/vim.h
index 0ab9d96173..c4baa911f1 100644
--- a/src/nvim/vim.h
+++ b/src/nvim/vim.h
@@ -155,6 +155,7 @@ enum {
   EXPAND_ARGLIST,
   EXPAND_DIFF_BUFFERS,
   EXPAND_BREAKPOINT,
+  EXPAND_SCRIPTNAMES,
   EXPAND_CHECKHEALTH,
   EXPAND_LUA,
 };