vim-patch:8.2.1398: autoload script sourced twice if sourced directly (#22622)

Problem:    Autoload script sourced twice if sourced directly.
Solution:   Do not source an autoload script again. (issue vim/vim#6644)

https://github.com/vim/vim/commit/daa2f36573db3e1df7eb1fdbc3a09a2815644048

Cherry-pick ret_sid changes from patch 8.2.0149.
Use do_in_runtimepath() as that's what source_runtime() calls in Nvim.

Co-authored-by: Bram Moolenaar <Bram@vim.org>

7 files changed, 59 insertions, 49 deletions

diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index 0f27040fd3..315ccd13e6 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -579,7 +579,7 @@ ArrayOf(String) nvim__get_runtime(Array pat, Boolean all, Dict(runtime) *opts, E
   if (source) {
     for (size_t i = 0; i < res.size; i++) {
       String name = res.items[i].data.string;
-      (void)do_source(name.data, false, DOSO_NONE);
+      (void)do_source(name.data, false, DOSO_NONE, NULL);
     }
   }
 
diff --git a/src/nvim/ex_session.c b/src/nvim/ex_session.c
index 8e3e68d9b7..855a5f7538 100644
--- a/src/nvim/ex_session.c
+++ b/src/nvim/ex_session.c
@@ -909,7 +909,7 @@ void ex_loadview(exarg_T *eap)
     return;
   }
 
-  if (do_source(fname, false, DOSO_NONE) == FAIL) {
+  if (do_source(fname, false, DOSO_NONE, NULL) == FAIL) {
     semsg(_(e_notopen), fname);
   }
   xfree(fname);
diff --git a/src/nvim/lua/executor.c b/src/nvim/lua/executor.c
index 078bc4fea9..11a02ea402 100644
--- a/src/nvim/lua/executor.c
+++ b/src/nvim/lua/executor.c
@@ -2061,10 +2061,15 @@ void nlua_set_sctx(sctx_T *current)
     break;
   }
   char *source_path = fix_fname(info->source + 1);
-  get_current_script_id(&source_path, current);
-  xfree(source_path);
-  current->sc_lnum = info->currentline;
+  int sid = find_script_by_name(source_path);
+  if (sid > 0) {
+    xfree(source_path);
+  } else {
+    new_script_item(source_path, &sid);
+  }
+  current->sc_sid = sid;
   current->sc_seq = -1;
+  current->sc_lnum = info->currentline;
 
 cleanup:
   xfree(info);
diff --git a/src/nvim/main.c b/src/nvim/main.c
index be1714b207..ea5f511fc6 100644
--- a/src/nvim/main.c
+++ b/src/nvim/main.c
@@ -1937,7 +1937,7 @@ static void do_system_initialization(void)
         dir_len += 1;
       }
       memcpy(vimrc + dir_len, path_tail, sizeof(path_tail));
-      if (do_source(vimrc, false, DOSO_NONE) != FAIL) {
+      if (do_source(vimrc, false, DOSO_NONE, NULL) != FAIL) {
         xfree(vimrc);
         xfree(config_dirs);
         return;
@@ -1949,7 +1949,7 @@ static void do_system_initialization(void)
 
 #ifdef SYS_VIMRC_FILE
   // Get system wide defaults, if the file name is defined.
-  (void)do_source(SYS_VIMRC_FILE, false, DOSO_NONE);
+  (void)do_source(SYS_VIMRC_FILE, false, DOSO_NONE, NULL);
 #endif
 }
 
@@ -1978,7 +1978,7 @@ static bool do_user_initialization(void)
 
   // init.lua
   if (os_path_exists(init_lua_path)
-      && do_source(init_lua_path, true, DOSO_VIMRC)) {
+      && do_source(init_lua_path, true, DOSO_VIMRC, NULL)) {
     if (os_path_exists(user_vimrc)) {
       semsg(_("E5422: Conflicting configs: \"%s\" \"%s\""), init_lua_path,
             user_vimrc);
@@ -1992,7 +1992,7 @@ static bool do_user_initialization(void)
   xfree(init_lua_path);
 
   // init.vim
-  if (do_source(user_vimrc, true, DOSO_VIMRC) != FAIL) {
+  if (do_source(user_vimrc, true, DOSO_VIMRC, NULL) != FAIL) {
     do_exrc = p_exrc;
     if (do_exrc) {
       do_exrc = (path_full_compare(VIMRC_FILE, user_vimrc, false, true) != kEqualFiles);
@@ -2018,7 +2018,7 @@ static bool do_user_initialization(void)
       memmove(vimrc, dir, dir_len);
       vimrc[dir_len] = PATHSEP;
       memmove(vimrc + dir_len + 1, path_tail, sizeof(path_tail));
-      if (do_source(vimrc, true, DOSO_VIMRC) != FAIL) {
+      if (do_source(vimrc, true, DOSO_VIMRC, NULL) != FAIL) {
         do_exrc = p_exrc;
         if (do_exrc) {
           do_exrc = (path_full_compare(VIMRC_FILE, vimrc, false, true) != kEqualFiles);
@@ -2084,7 +2084,7 @@ static void source_startup_scripts(const mparm_T *const parmp)
         || strequal(parmp->use_vimrc, "NORC")) {
       // Do nothing.
     } else {
-      if (do_source(parmp->use_vimrc, false, DOSO_NONE) != OK) {
+      if (do_source(parmp->use_vimrc, false, DOSO_NONE, NULL) != OK) {
         semsg(_("E282: Cannot read from \"%s\""), parmp->use_vimrc);
       }
     }
diff --git a/src/nvim/runtime.c b/src/nvim/runtime.c
index c316b61082..c9667d58ed 100644
--- a/src/nvim/runtime.c
+++ b/src/nvim/runtime.c
@@ -78,6 +78,8 @@ garray_T script_items = { 0, 0, sizeof(scriptitem_T *), 20, NULL };
 /// The names of packages that once were loaded are remembered.
 static garray_T ga_loaded = { 0, 0, sizeof(char *), 4, NULL };
 
+static int last_current_SID_seq = 0;
+
 /// Initialize the execution stack.
 void estack_init(void)
 {
@@ -266,7 +268,7 @@ void set_context_in_runtime_cmd(expand_T *xp, const char *arg)
 
 static void source_callback(char *fname, void *cookie)
 {
-  (void)do_source(fname, false, DOSO_NONE);
+  (void)do_source(fname, false, DOSO_NONE, cookie);
 }
 
 /// Find the file "name" in all directories in "path" and invoke
@@ -855,7 +857,7 @@ static void source_all_matches(char *pat)
   }
 
   for (int i = 0; i < num_files; i++) {
-    (void)do_source(files[i], false, DOSO_NONE);
+    (void)do_source(files[i], false, DOSO_NONE, NULL);
   }
   FreeWild(num_files, files);
 }
@@ -1701,7 +1703,7 @@ static void cmd_source(char *fname, exarg_T *eap)
                || eap->cstack->cs_idx >= 0);
 
     // ":source" read ex commands
-  } else if (do_source(fname, false, DOSO_NONE) == FAIL) {
+  } else if (do_source(fname, false, DOSO_NONE, NULL) == FAIL) {
     semsg(_(e_notopen), fname);
   }
 }
@@ -1954,9 +1956,12 @@ int do_source_str(const char *cmd, const char *traceback_name)
 /// @param fname
 /// @param check_other  check for .vimrc and _vimrc
 /// @param is_vimrc     DOSO_ value
+/// @param ret_sid      if not NULL and we loaded the script before, don't load it again
 ///
 /// @return  FAIL if file could not be opened, OK otherwise
-int do_source(char *fname, int check_other, int is_vimrc)
+///
+/// If a scriptitem_T was found or created "*ret_sid" is set to the SID.
+int do_source(char *fname, int check_other, int is_vimrc, int *ret_sid)
 {
   struct source_cookie cookie;
   char *p;
@@ -1982,6 +1987,15 @@ int do_source(char *fname, int check_other, int is_vimrc)
     goto theend;
   }
 
+  // See if we loaded this script before.
+  int sid = find_script_by_name(fname_exp);
+  if (sid > 0 && ret_sid != NULL) {
+    // Already loaded and no need to load again, return here.
+    *ret_sid = sid;
+    retval = OK;
+    goto theend;
+  }
+
   // Apply SourceCmd autocommands, they should get the file and source it.
   if (has_autocmd(EVENT_SOURCECMD, fname_exp, NULL)
       && apply_autocmds(EVENT_SOURCECMD, fname_exp, fname_exp,
@@ -2080,7 +2094,24 @@ int do_source(char *fname, int check_other, int is_vimrc)
   save_funccal(&funccalp_entry);
 
   const sctx_T save_current_sctx = current_sctx;
-  si = get_current_script_id(&fname_exp, &current_sctx);
+
+  current_sctx.sc_lnum = 0;
+
+  // Always use a new sequence number.
+  current_sctx.sc_seq = ++last_current_SID_seq;
+
+  if (sid > 0) {
+    // loading the same script again
+    si = SCRIPT_ITEM(sid);
+  } else {
+    // It's new, generate a new SID.
+    si = new_script_item(fname_exp, &sid);
+    fname_exp = xstrdup(si->sn_name);  // used for autocmd
+    if (ret_sid != NULL) {
+      *ret_sid = sid;
+    }
+  }
+  current_sctx.sc_sid = sid;
 
   // Keep the sourcing name/lnum, for recursive calls.
   estack_push(ETYPE_SCRIPT, si->sn_name, 0);
@@ -2192,7 +2223,7 @@ theend:
 
 /// Find an already loaded script "name".
 /// If found returns its script ID.  If not found returns -1.
-static int find_script_by_name(char *name)
+int find_script_by_name(char *name)
 {
   assert(script_items.ga_len >= 0);
   for (int sid = script_items.ga_len; sid > 0; sid--) {
@@ -2209,35 +2240,6 @@ static int find_script_by_name(char *name)
   return -1;
 }
 
-/// Check if fname was sourced before to finds its SID.
-/// If it's new, generate a new SID.
-///
-/// @param[in,out] fnamep  pointer to file path of script
-/// @param[out] ret_sctx   sctx of this script
-scriptitem_T *get_current_script_id(char **fnamep, sctx_T *ret_sctx)
-{
-  static int last_current_SID_seq = 0;
-
-  scriptitem_T *si;
-  int sid = find_script_by_name(*fnamep);
-  if (sid > 0) {
-    si = SCRIPT_ITEM(sid);
-  } else {
-    si = new_script_item(*fnamep, &sid);
-    *fnamep = xstrdup(si->sn_name);
-  }
-
-  sctx_T script_sctx = { .sc_seq = ++last_current_SID_seq,
-                         .sc_lnum = 0,
-                         .sc_sid = sid };
-
-  if (ret_sctx != NULL) {
-    *ret_sctx = script_sctx;
-  }
-
-  return si;
-}
-
 /// ":scriptnames"
 void ex_scriptnames(exarg_T *eap)
 {
@@ -2704,7 +2706,9 @@ bool script_autoload(const char *const name, const size_t name_len, const bool r
     }
 
     // Try loading the package from $VIMRUNTIME/autoload/<name>.vim
-    if (source_runtime(scriptname, 0) == OK) {
+    // Use "ret_sid" to avoid loading the same script again.
+    int ret_sid;
+    if (do_in_runtimepath(scriptname, 0, source_callback, &ret_sid) == OK) {
       ret = true;
     }
   }
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index d4161b9ca2..14fef19399 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -4026,7 +4026,7 @@ static void syn_cmd_include(exarg_T *eap, int syncing)
   prev_toplvl_grp = curwin->w_s->b_syn_topgrp;
   curwin->w_s->b_syn_topgrp = sgl_id;
   if (source
-      ? do_source(eap->arg, false, DOSO_NONE) == FAIL
+      ? do_source(eap->arg, false, DOSO_NONE, NULL) == FAIL
       : source_runtime(eap->arg, DIP_ALL) == FAIL) {
     semsg(_(e_notopen), eap->arg);
   }
diff --git a/test/old/testdir/sautest/autoload/sourced.vim b/test/old/testdir/sautest/autoload/sourced.vim
index f69f00cb53..aac96b11ce 100644
--- a/test/old/testdir/sautest/autoload/sourced.vim
+++ b/test/old/testdir/sautest/autoload/sourced.vim
@@ -1,3 +1,4 @@
 let g:loaded_sourced_vim += 1
-func! sourced#something()
+func sourced#something()
 endfunc
+call sourced#something()