Merge pull request #23944 from neovim/backport-23943-to-release-0.9

[Backport release-0.9] fix(events): don't expand non-file as file name

src/nvim/autocmd.c

@@ -1751,6 +1751,7 @@ bool apply_autocmds_group(event_T event, char *fname, char *fname_io, bool force
 
   // Save the autocmd_* variables and info about the current buffer.
   char *save_autocmd_fname = autocmd_fname;
+  bool save_autocmd_fname_full = autocmd_fname_full;
   int save_autocmd_bufnr = autocmd_bufnr;
   char *save_autocmd_match = autocmd_match;
   int save_autocmd_busy = autocmd_busy;
@@ -1779,6 +1780,7 @@ bool apply_autocmds_group(event_T event, char *fname, char *fname_io, bool force
     // Allocate MAXPATHL for when eval_vars() resolves the fullpath.
     autocmd_fname = xstrnsave(autocmd_fname, MAXPATHL);
   }
+  autocmd_fname_full = false;  // call FullName_save() later
 
   // Set the buffer number to be used for <abuf>.
   if (buf == NULL) {
@@ -1826,6 +1828,7 @@ bool apply_autocmds_group(event_T event, char *fname, char *fname_io, bool force
         || event == EVENT_USER || event == EVENT_WINCLOSED
         || event == EVENT_WINRESIZED || event == EVENT_WINSCROLLED) {
       fname = xstrdup(fname);
+      autocmd_fname_full = true;  // don't expand it later
     } else {
       fname = FullName_save(fname, false);
     }
@@ -1959,6 +1962,7 @@ bool apply_autocmds_group(event_T event, char *fname, char *fname_io, bool force
   estack_pop();
   xfree(autocmd_fname);
   autocmd_fname = save_autocmd_fname;
+  autocmd_fname_full = save_autocmd_fname_full;
   autocmd_bufnr = save_autocmd_bufnr;
   autocmd_match = save_autocmd_match;
   current_sctx = save_current_sctx;

src/nvim/eval.c

@@ -8192,6 +8192,7 @@ typval_T eval_call_provider(char *provider, char *method, list_T *arguments, boo
     .es_entry = ((estack_T *)exestack.ga_data)[exestack.ga_len - 1],
     .autocmd_fname = autocmd_fname,
     .autocmd_match = autocmd_match,
+    .autocmd_fname_full = autocmd_fname_full,
     .autocmd_bufnr = autocmd_bufnr,
     .funccalp = (void *)get_current_funccal()
   };

src/nvim/eval/funcs.c

@@ -6604,6 +6604,7 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 
   sctx_T save_current_sctx;
   char *save_autocmd_fname, *save_autocmd_match;
+  bool save_autocmd_fname_full;
   int save_autocmd_bufnr;
   funccal_entry_T funccal_entry;
 
@@ -6613,6 +6614,7 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     save_current_sctx = current_sctx;
     save_autocmd_fname = autocmd_fname;
     save_autocmd_match = autocmd_match;
+    save_autocmd_fname_full = autocmd_fname_full;
     save_autocmd_bufnr = autocmd_bufnr;
     save_funccal(&funccal_entry);
 
@@ -6621,6 +6623,7 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     ((estack_T *)exestack.ga_data)[exestack.ga_len++] = provider_caller_scope.es_entry;
     autocmd_fname = provider_caller_scope.autocmd_fname;
     autocmd_match = provider_caller_scope.autocmd_match;
+    autocmd_fname_full = provider_caller_scope.autocmd_fname_full;
     autocmd_bufnr = provider_caller_scope.autocmd_bufnr;
     set_current_funccal((funccall_T *)(provider_caller_scope.funccalp));
   }
@@ -6638,6 +6641,7 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     exestack.ga_len--;
     autocmd_fname = save_autocmd_fname;
     autocmd_match = save_autocmd_match;
+    autocmd_fname_full = save_autocmd_fname_full;
     autocmd_bufnr = save_autocmd_bufnr;
     restore_funccal();
   }

src/nvim/ex_docmd.c

@@ -6864,12 +6864,10 @@ char *eval_vars(char *src, const char *srcstart, size_t *usedlen, linenr_T *lnum
       break;
 
     case SPEC_AFILE:  // file name for autocommand
-      if (autocmd_fname != NULL
-          && !path_is_absolute(autocmd_fname)
-          // For CmdlineEnter and related events, <afile> is not a path! #9348
-          && !strequal("/", autocmd_fname)) {
+      if (autocmd_fname != NULL && !autocmd_fname_full) {
         // Still need to turn the fname into a full path.  It was
         // postponed to avoid a delay when <afile> is not used.
+        autocmd_fname_full = true;
         result = FullName_save(autocmd_fname, false);
         // Copy into `autocmd_fname`, don't reassign it. #8165
         xstrlcpy(autocmd_fname, result, MAXPATHL);

src/nvim/globals.h

@@ -336,6 +336,7 @@ EXTERN struct caller_scope {
   sctx_T script_ctx;
   estack_T es_entry;
   char *autocmd_fname, *autocmd_match;
+  bool autocmd_fname_full;
   int autocmd_bufnr;
   void *funccalp;
 } provider_caller_scope;
@@ -759,6 +760,7 @@ EXTERN char *last_cmdline INIT(= NULL);        // last command line (for ":)
 EXTERN char *repeat_cmdline INIT(= NULL);      // command line for "."
 EXTERN char *new_last_cmdline INIT(= NULL);    // new value for last_cmdline
 EXTERN char *autocmd_fname INIT(= NULL);       // fname for <afile> on cmdline
+EXTERN bool autocmd_fname_full INIT(= false);  // autocmd_fname is full path
 EXTERN int autocmd_bufnr INIT(= 0);            // fnum for <abuf> on cmdline
 EXTERN char *autocmd_match INIT(= NULL);       // name for <amatch> on cmdline
 EXTERN bool did_cursorhold INIT(= false);      // set when CursorHold t'gerd

src/nvim/path.c

@@ -2082,17 +2082,17 @@ char *path_shorten_fname(char *full_path, char *dir_name)
   assert(dir_name != NULL);
   size_t len = strlen(dir_name);
 
-  // If dir_name is a path head, full_path can always be made relative.
-  if (len == (size_t)path_head_length() && is_path_head(dir_name)) {
-    return full_path + len;
-  }
-
   // If full_path and dir_name do not match, it's impossible to make one
   // relative to the other.
   if (path_fnamencmp(dir_name, full_path, len) != 0) {
     return NULL;
   }
 
+  // If dir_name is a path head, full_path can always be made relative.
+  if (len == (size_t)path_head_length() && is_path_head(dir_name)) {
+    return full_path + len;
+  }
+
   char *p = full_path + len;
 
   // If *p is not pointing to a path separator, this means that full_path's

test/functional/api/autocmd_spec.lua

@@ -228,23 +228,28 @@ describe('autocmd api', function()
     end)
 
     it('receives an args table', function()
-      local res = exec_lua [[
-        local group_id = vim.api.nvim_create_augroup("TestGroup", {})
-        local autocmd_id = vim.api.nvim_create_autocmd("User", {
+      local group_id = meths.create_augroup("TestGroup", {})
+      -- Having an existing autocmd calling expand("<afile>") shouldn't change args #18964
+      meths.create_autocmd('User', {
+        group = 'TestGroup',
+        pattern = 'Te*',
+        command = 'call expand("<afile>")',
+      })
+
+      local autocmd_id = exec_lua [[
+        return vim.api.nvim_create_autocmd("User", {
           group = "TestGroup",
           pattern = "Te*",
           callback = function(args)
             vim.g.autocmd_args = args
           end,
         })
-
-        return {group_id, autocmd_id}
       ]]
 
       meths.exec_autocmds("User", {pattern = "Test pattern"})
       eq({
-        id = res[2],
-        group = res[1],
+        id = autocmd_id,
+        group = group_id,
         event = "User",
         match = "Test pattern",
         file = "Test pattern",
@@ -252,27 +257,24 @@ describe('autocmd api', function()
       }, meths.get_var("autocmd_args"))
 
       -- Test without a group
-      res = exec_lua [[
-        local autocmd_id = vim.api.nvim_create_autocmd("User", {
+      autocmd_id = exec_lua [[
+        return vim.api.nvim_create_autocmd("User", {
           pattern = "*",
           callback = function(args)
             vim.g.autocmd_args = args
           end,
         })
-
-        return {autocmd_id}
       ]]
 
       meths.exec_autocmds("User", {pattern = "some_pat"})
       eq({
-        id = res[1],
+        id = autocmd_id,
         group = nil,
         event = "User",
         match = "some_pat",
         file = "some_pat",
         buf = 1,
       }, meths.get_var("autocmd_args"))
-
     end)
 
     it('can receive arbitrary data', function()