feat(:source, nvim_exec): support script-local variables

Based on #13143 (and #11507) with changes:

 - Omit script_type_E. Use sn_name == NULL to determine anon items.
 - Keep SID_STR. Used by anon :source for .lua files (no item).
 - Show SID in get_scriptname output (:verbose set).
 - Factor item creation into new_script_item.
 - Leave sc_seq = 0 (anon scripts don't re-use the same item when re-sourced).
 - Add tests for anon :source.

Co-authored-by: Vikram Pal <vikrampal659@gmail.com>
Co-authored-by: Justin M. Keyes <justinkz@gmail.com>

2 files changed, 37 insertions, 21 deletions

diff --git a/src/nvim/ex_cmds2.c b/src/nvim/ex_cmds2.c
index c3cde2f15a..c421d3991c 100644
--- a/src/nvim/ex_cmds2.c
+++ b/src/nvim/ex_cmds2.c
@@ -1939,6 +1939,29 @@ static char_u *get_str_line(int c, void *cookie, int indent, bool do_concat)
   return ga.ga_data;
 }
 
+/// Create a new script item and allocate script-local vars. @see new_script_vars
+///
+/// @param  name  File name of the script. NULL for anonymous :source.
+/// @param[out]  sid_out  SID of the new item.
+/// @return pointer to the created script item.
+static scriptitem_T *new_script_item(char_u *const name, scid_T *const sid_out)
+{
+  static scid_T last_current_SID = 0;
+  const scid_T sid = ++last_current_SID;
+  if (sid_out != NULL) {
+    *sid_out = sid;
+  }
+  ga_grow(&script_items, (int)(sid - script_items.ga_len));
+  while (script_items.ga_len < sid) {
+    script_items.ga_len++;
+    SCRIPT_ITEM(script_items.ga_len).sn_name = NULL;
+    SCRIPT_ITEM(script_items.ga_len).sn_prof_on = false;
+  }
+  SCRIPT_ITEM(sid).sn_name = name;
+  new_script_vars(sid);  // Allocate the local script variables to use for this script.
+  return &SCRIPT_ITEM(sid);
+}
+
 static int source_using_linegetter(void *cookie, LineGetter fgetline, const char *traceback_name)
 {
   char_u *save_sourcing_name = sourcing_name;
@@ -1955,7 +1978,7 @@ static int source_using_linegetter(void *cookie, LineGetter fgetline, const char
   sourcing_lnum = 0;
 
   const sctx_T save_current_sctx = current_sctx;
-  current_sctx.sc_sid = SID_STR;
+  new_script_item(NULL, &current_sctx.sc_sid);
   current_sctx.sc_seq = 0;
   current_sctx.sc_lnum = save_sourcing_lnum;
   funccal_entry_T entry;
@@ -2036,7 +2059,6 @@ int do_source(char_u *fname, int check_other, int is_vimrc)
   char_u *fname_exp;
   char_u *firstline = NULL;
   int retval = FAIL;
-  static scid_T last_current_SID = 0;
   static int last_current_SID_seq = 0;
   int save_debug_break_level = debug_break_level;
   scriptitem_T *si = NULL;
@@ -2183,15 +2205,7 @@ int do_source(char_u *fname, int check_other, int is_vimrc)
     }
   }
   if (current_sctx.sc_sid == 0) {
-    current_sctx.sc_sid = ++last_current_SID;
-    ga_grow(&script_items, (int)(current_sctx.sc_sid - script_items.ga_len));
-    while (script_items.ga_len < current_sctx.sc_sid) {
-      script_items.ga_len++;
-      SCRIPT_ITEM(script_items.ga_len).sn_name = NULL;
-      SCRIPT_ITEM(script_items.ga_len).sn_prof_on = false;
-    }
-    si = &SCRIPT_ITEM(current_sctx.sc_sid);
-    si->sn_name = fname_exp;
+    si = new_script_item(fname_exp, &current_sctx.sc_sid);
     fname_exp = vim_strsave(si->sn_name);  // used for autocmd
     if (file_id_ok) {
       si->file_id_valid = true;
@@ -2199,9 +2213,6 @@ int do_source(char_u *fname, int check_other, int is_vimrc)
     } else {
       si->file_id_valid = false;
     }
-
-    // Allocate the local script variables to use for this script.
-    new_script_vars(current_sctx.sc_sid);
   }
 
   if (l_do_profiling == PROF_YES) {
@@ -2375,16 +2386,21 @@ char_u *get_scriptname(LastSet last_set, bool *should_free)
   case SID_LUA:
     return (char_u *)_("Lua");
   case SID_API_CLIENT:
-    vim_snprintf((char *)IObuff, IOSIZE,
-                 _("API client (channel id %" PRIu64 ")"),
-                 last_set.channel_id);
+    snprintf((char *)IObuff, IOSIZE, _("API client (channel id %" PRIu64 ")"), last_set.channel_id);
     return IObuff;
   case SID_STR:
     return (char_u *)_("anonymous :source");
-  default:
+  default: {
+    char_u *const sname = SCRIPT_ITEM(last_set.script_ctx.sc_sid).sn_name;
+    if (sname == NULL) {
+      snprintf((char *)IObuff, IOSIZE, _("anonymous :source (script id %d)"),
+               last_set.script_ctx.sc_sid);
+      return IObuff;
+    }
+
     *should_free = true;
-    return home_replace_save(NULL,
-                             SCRIPT_ITEM(last_set.script_ctx.sc_sid).sn_name);
+    return home_replace_save(NULL, sname);
+  }
   }
 }
 
diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index 182e88083a..435949379b 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -335,7 +335,7 @@ EXTERN int garbage_collect_at_exit INIT(= false);
 #define SID_WINLAYOUT   -7      // changing window size
 #define SID_LUA         -8      // for Lua scripts/chunks
 #define SID_API_CLIENT  -9      // for API clients
-#define SID_STR         -10     // for sourcing a string
+#define SID_STR         -10     // for sourcing a string with no script item
 
 // Script CTX being sourced or was sourced to define the current function.
 EXTERN sctx_T current_sctx INIT(= { 0 COMMA 0 COMMA 0 });