Merge #15293 Vimscript "method" syntax

Port VimL's method call syntax - vim-patch:8.1.{1638,1800,1803,1807,1809,1816,1820,1821,1828,1834,1835,1861,1863,1878,1879,1888,1909,1911,1912}

4 files changed, 164 insertions, 63 deletions

diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index 4e409cca50..8a1258efd4 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -175,6 +175,53 @@ const VimLFuncDef *find_internal_func(const char *const name)
   return find_internal_func_gperf(name, len);
 }
 
+int call_internal_func(const char_u *const fname, const int argcount,
+                       typval_T *const argvars, typval_T *const rettv)
+  FUNC_ATTR_NONNULL_ALL
+{
+  const VimLFuncDef *const fdef = find_internal_func((const char *)fname);
+  if (fdef == NULL) {
+    return ERROR_UNKNOWN;
+  } else if (argcount < fdef->min_argc) {
+    return ERROR_TOOFEW;
+  } else if (argcount > fdef->max_argc) {
+    return ERROR_TOOMANY;
+  }
+  argvars[argcount].v_type = VAR_UNKNOWN;
+  fdef->func(argvars, rettv, fdef->data);
+  return ERROR_NONE;
+}
+
+/// Invoke a method for base->method().
+int call_internal_method(const char_u *const fname, const int argcount,
+                         typval_T *const argvars, typval_T *const rettv,
+                         typval_T *const basetv)
+  FUNC_ATTR_NONNULL_ALL
+{
+  const VimLFuncDef *const fdef = find_internal_func((const char *)fname);
+  if (fdef == NULL) {
+    return ERROR_UNKNOWN;
+  } else if (fdef->base_arg == BASE_NONE) {
+    return ERROR_NOTMETHOD;
+  } else if (argcount + 1 < fdef->min_argc) {
+    return ERROR_TOOFEW;
+  } else if (argcount + 1 > fdef->max_argc) {
+    return ERROR_TOOMANY;
+  }
+
+  typval_T argv[MAX_FUNC_ARGS + 1];
+  const ptrdiff_t base_index
+      = fdef->base_arg == BASE_LAST ? argcount : fdef->base_arg - 1;
+  memcpy(argv, argvars, base_index * sizeof(typval_T));
+  argv[base_index] = *basetv;
+  memcpy(argv + base_index + 1, argvars + base_index,
+         (argcount - base_index) * sizeof(typval_T));
+  argv[argcount + 1].v_type = VAR_UNKNOWN;
+
+  fdef->func(argv, rettv, fdef->data);
+  return ERROR_NONE;
+}
+
 /*
  * Return TRUE for a non-zero Number and a non-empty String.
  */
@@ -9420,7 +9467,6 @@ static int item_compare2(const void *s1, const void *s2, bool keep_zero)
   int res;
   typval_T rettv;
   typval_T argv[3];
-  int dummy;
   const char *func_name;
   partial_T *partial = sortinfo->item_compare_partial;
 
@@ -9444,10 +9490,11 @@ static int item_compare2(const void *s1, const void *s2, bool keep_zero)
   tv_copy(TV_LIST_ITEM_TV(si2->item), &argv[1]);
 
   rettv.v_type = VAR_UNKNOWN;  // tv_clear() uses this
-  res = call_func((const char_u *)func_name,
-                  -1,
-                  &rettv, 2, argv, NULL, 0L, 0L, &dummy, true,
-                  partial, sortinfo->item_compare_selfdict);
+  funcexe_T funcexe = FUNCEXE_INIT;
+  funcexe.evaluate = true;
+  funcexe.partial = partial;
+  funcexe.selfdict = sortinfo->item_compare_selfdict;
+  res = call_func((const char_u *)func_name, -1, &rettv, 2, argv, &funcexe);
   tv_clear(&argv[0]);
   tv_clear(&argv[1]);
 
diff --git a/src/nvim/eval/funcs.h b/src/nvim/eval/funcs.h
index a343290734..c6a0cb959e 100644
--- a/src/nvim/eval/funcs.h
+++ b/src/nvim/eval/funcs.h
@@ -9,11 +9,16 @@ typedef void (*FunPtr)(void);
 /// Prototype of C function that implements VimL function
 typedef void (*VimLFunc)(typval_T *args, typval_T *rvar, FunPtr data);
 
+/// Special flags for base_arg @see VimLFuncDef
+#define BASE_NONE 0          ///< Not a method (no base argument).
+#define BASE_LAST UINT8_MAX  ///< Use the last argument as the method base.
+
 /// Structure holding VimL function definition
 typedef struct fst {
   char *name;        ///< Name of the function.
   uint8_t min_argc;  ///< Minimal number of arguments.
   uint8_t max_argc;  ///< Maximal number of arguments.
+  uint8_t base_arg;  ///< Method base arg # (1-indexed), BASE_NONE or BASE_LAST.
   VimLFunc func;     ///< Function implementation.
   FunPtr data;       ///< Userdata for function implementation.
 } VimLFuncDef;
diff --git a/src/nvim/eval/userfunc.c b/src/nvim/eval/userfunc.c
index deddec413b..4184e4d922 100644
--- a/src/nvim/eval/userfunc.c
+++ b/src/nvim/eval/userfunc.c
@@ -414,12 +414,7 @@ get_func_tv(
     int len,                // length of "name" or -1 to use strlen()
     typval_T *rettv,
     char_u **arg,           // argument, pointing to the '('
-    linenr_T firstline,     // first line of range
-    linenr_T lastline,      // last line of range
-    int *doesrange,         // return: function handled range
-    int evaluate,
-    partial_T *partial,     // for extra arguments
-    dict_T *selfdict        // Dictionary for "self"
+    funcexe_T *funcexe      // various values
 )
 {
   char_u      *argp;
@@ -431,12 +426,13 @@ get_func_tv(
    * Get the arguments.
    */
   argp = *arg;
-  while (argcount < MAX_FUNC_ARGS - (partial == NULL ? 0 : partial->pt_argc)) {
+  while (argcount < MAX_FUNC_ARGS
+         - (funcexe->partial == NULL ? 0 : funcexe->partial->pt_argc)) {
     argp = skipwhite(argp + 1);             // skip the '(' or ','
     if (*argp == ')' || *argp == ',' || *argp == NUL) {
       break;
     }
-    if (eval1(&argp, &argvars[argcount], evaluate) == FAIL) {
+    if (eval1(&argp, &argvars[argcount], funcexe->evaluate) == FAIL) {
       ret = FAIL;
       break;
     }
@@ -463,9 +459,7 @@ get_func_tv(
         ((typval_T **)funcargs.ga_data)[funcargs.ga_len++] = &argvars[i];
       }
     }
-    ret = call_func(name, len, rettv, argcount, argvars, NULL,
-                    firstline, lastline, doesrange, evaluate,
-                    partial, selfdict);
+    ret = call_func(name, len, rettv, argcount, argvars, funcexe);
 
     funcargs.ga_len -= i;
   } else if (!aborting()) {
@@ -1367,7 +1361,6 @@ int func_call(char_u *name, typval_T *args, partial_T *partial,
 {
   typval_T argv[MAX_FUNC_ARGS + 1];
   int argc = 0;
-  int dummy;
   int r = 0;
 
   TV_LIST_ITER(args->vval.v_list, item, {
@@ -1380,9 +1373,13 @@ int func_call(char_u *name, typval_T *args, partial_T *partial,
     tv_copy(TV_LIST_ITEM_TV(item), &argv[argc++]);
   });
 
-  r = call_func(name, -1, rettv, argc, argv, NULL,
-                curwin->w_cursor.lnum, curwin->w_cursor.lnum,
-                &dummy, true, partial, selfdict);
+  funcexe_T funcexe = FUNCEXE_INIT;
+  funcexe.firstline = curwin->w_cursor.lnum;
+  funcexe.lastline = curwin->w_cursor.lnum;
+  funcexe.evaluate = true;
+  funcexe.partial = partial;
+  funcexe.selfdict = selfdict;
+  r = call_func(name, -1, rettv, argc, argv, &funcexe);
 
 func_call_skip_call:
   // Free the arguments.
@@ -1402,6 +1399,9 @@ static void user_func_error(int error, const char_u *name)
     case ERROR_UNKNOWN:
       emsg_funcname(N_("E117: Unknown function: %s"), name);
       break;
+    case ERROR_NOTMETHOD:
+      emsg_funcname(N_("E276: Cannot use function as a method: %s"), name);
+      break;
     case ERROR_DELETED:
       emsg_funcname(N_("E933: Function was deleted: %s"), name);
       break;
@@ -1423,12 +1423,25 @@ static void user_func_error(int error, const char_u *name)
   }
 }
 
+/// Used by call_func to add a method base (if any) to a function argument list
+/// as the first argument. @see call_func
+static void argv_add_base(typval_T *const basetv, typval_T **const argvars,
+                          int *const argcount, typval_T *const new_argvars,
+                          int *const argv_base)
+  FUNC_ATTR_NONNULL_ARG(2, 3, 4, 5)
+{
+  if (basetv != NULL) {
+    // Method call: base->Method()
+    memmove(&new_argvars[1], *argvars, sizeof(typval_T) * (*argcount));
+    new_argvars[0] = *basetv;
+    (*argcount)++;
+    *argvars = new_argvars;
+    *argv_base = 1;
+  }
+}
+
 /// Call a function with its resolved parameters
 ///
-/// "argv_func", when not NULL, can be used to fill in arguments only when the
-/// invoked function uses them. It is called like this:
-///   new_argcount = argv_func(current_argcount, argv, called_func_argcount)
-///
 /// @return FAIL if function cannot be called, else OK (even if an error
 ///         occurred while executing the function! Set `msg_list` to capture
 ///         the error, see do_cmdline()).
@@ -1440,15 +1453,9 @@ call_func(
     int argcount_in,                // number of "argvars"
     typval_T *argvars_in,           // vars for arguments, must have "argcount"
                                     // PLUS ONE elements!
-    ArgvFunc argv_func,             // function to fill in argvars
-    linenr_T firstline,             // first line of range
-    linenr_T lastline,              // last line of range
-    int *doesrange,                 // [out] function handled range
-    bool evaluate,
-    partial_T *partial,             // optional, can be NULL
-    dict_T *selfdict_in             // Dictionary for "self"
+    funcexe_T *funcexe              // more arguments
 )
-  FUNC_ATTR_NONNULL_ARG(1, 3, 5, 9)
+  FUNC_ATTR_NONNULL_ARG(1, 3, 5, 6)
 {
   int ret = FAIL;
   int error = ERROR_NONE;
@@ -1459,9 +1466,12 @@ call_func(
   char_u *name = NULL;
   int argcount = argcount_in;
   typval_T *argvars = argvars_in;
-  dict_T *selfdict = selfdict_in;
-  typval_T argv[MAX_FUNC_ARGS + 1];  // used when "partial" is not NULL
+  dict_T *selfdict = funcexe->selfdict;
+  typval_T argv[MAX_FUNC_ARGS + 1];  // used when "partial" or
+                                     // "funcexe->basetv" is not NULL
   int argv_clear = 0;
+  int argv_base = 0;
+  partial_T *partial = funcexe->partial;
 
   // Initialize rettv so that it is safe for caller to invoke clear_tv(rettv)
   // even when call_func() returns FAIL.
@@ -1480,14 +1490,15 @@ call_func(
     fname = fname_trans_sid(name, fname_buf, &tofree, &error);
   }
 
-  *doesrange = false;
+  if (funcexe->doesrange != NULL) {
+    *funcexe->doesrange = false;
+  }
 
   if (partial != NULL) {
     // When the function has a partial with a dict and there is a dict
     // argument, use the dict argument. That is backwards compatible.
     // When the dict was bound explicitly use the one from the partial.
-    if (partial->pt_dict != NULL
-        && (selfdict_in == NULL || !partial->pt_auto)) {
+    if (partial->pt_dict != NULL && (selfdict == NULL || !partial->pt_auto)) {
       selfdict = partial->pt_dict;
     }
     if (error == ERROR_NONE && partial->pt_argc > 0) {
@@ -1506,7 +1517,7 @@ call_func(
     }
   }
 
-  if (error == ERROR_NONE && evaluate) {
+  if (error == ERROR_NONE && funcexe->evaluate) {
     char_u *rfname = fname;
 
     // Ignore "g:" before a function name.
@@ -1521,7 +1532,12 @@ call_func(
     if (is_luafunc(partial)) {
       if (len > 0) {
         error = ERROR_NONE;
+        argv_add_base(funcexe->basetv, &argvars, &argcount, argv, &argv_base);
         nlua_typval_call((const char *)funcname, len, argvars, argcount, rettv);
+      } else {
+        // v:lua was called directly; show its name in the emsg
+        XFREE_CLEAR(name);
+        funcname = (const char_u *)"v:lua";
       }
     } else if (fp != NULL || !builtin_function((const char *)rfname, -1)) {
       // User defined function.
@@ -1549,13 +1565,16 @@ call_func(
         cfunc_T cb = fp->uf_cb;
         error = (*cb)(argcount, argvars, rettv, fp->uf_cb_state);
       } else if (fp != NULL) {
-        if (argv_func != NULL) {
+        if (funcexe->argv_func != NULL) {
           // postponed filling in the arguments, do it now
-          argcount = argv_func(argcount, argvars, argv_clear,
-                               fp->uf_args.ga_len);
+          argcount = funcexe->argv_func(argcount, argvars, argv_clear,
+                                        fp->uf_args.ga_len);
         }
-        if (fp->uf_flags & FC_RANGE) {
-          *doesrange = true;
+
+        argv_add_base(funcexe->basetv, &argvars, &argcount, argv, &argv_base);
+
+        if (fp->uf_flags & FC_RANGE && funcexe->doesrange != NULL) {
+          *funcexe->doesrange = true;
         }
         if (argcount < fp->uf_args.ga_len - fp->uf_def_args.ga_len) {
           error = ERROR_TOOFEW;
@@ -1565,25 +1584,20 @@ call_func(
           error = ERROR_DICT;
         } else {
           // Call the user function.
-          call_user_func(fp, argcount, argvars, rettv, firstline, lastline,
+          call_user_func(fp, argcount, argvars, rettv, funcexe->firstline,
+                         funcexe->lastline,
                          (fp->uf_flags & FC_DICT) ? selfdict : NULL);
           error = ERROR_NONE;
         }
       }
+    } else if (funcexe->basetv != NULL) {
+      // expr->method(): Find the method name in the table, call its
+      // implementation with the base as one of the arguments.
+      error = call_internal_method(fname, argcount, argvars, rettv,
+                                   funcexe->basetv);
     } else {
       // Find the function name in the table, call its implementation.
-      const VimLFuncDef *const fdef = find_internal_func((const char *)fname);
-      if (fdef != NULL) {
-        if (argcount < fdef->min_argc) {
-          error = ERROR_TOOFEW;
-        } else if (argcount > fdef->max_argc) {
-          error = ERROR_TOOMANY;
-        } else {
-          argvars[argcount].v_type = VAR_UNKNOWN;
-          fdef->func(argvars, rettv, fdef->data);
-          error = ERROR_NONE;
-        }
-      }
+      error = call_internal_func(fname, argcount, argvars, rettv);
     }
     /*
      * The function call (or "FuncUndefined" autocommand sequence) might
@@ -1607,9 +1621,11 @@ theend:
     user_func_error(error, (name != NULL) ? name : funcname);
   }
 
+  // clear the copies made from the partial
   while (argv_clear > 0) {
-    tv_clear(&argv[--argv_clear]);
+    tv_clear(&argv[--argv_clear + argv_base]);
   }
+
   xfree(tofree);
   xfree(name);
 
@@ -2901,7 +2917,7 @@ void ex_call(exarg_T *eap)
   int len;
   typval_T rettv;
   linenr_T lnum;
-  int doesrange;
+  bool doesrange;
   bool failed = false;
   funcdict_T fudi;
   partial_T *partial = NULL;
@@ -2947,7 +2963,7 @@ void ex_call(exarg_T *eap)
   rettv.v_type = VAR_UNKNOWN;  // tv_clear() uses this.
 
   if (*startarg != '(') {
-    EMSG2(_("E107: Missing parentheses: %s"), eap->arg);
+    EMSG2(_(e_missingparen), eap->arg);
     goto end;
   }
 
@@ -2965,15 +2981,22 @@ void ex_call(exarg_T *eap)
       curwin->w_cursor.coladd = 0;
     }
     arg = startarg;
-    if (get_func_tv(name, -1, &rettv, &arg,
-                    eap->line1, eap->line2, &doesrange,
-                    true, partial, fudi.fd_dict) == FAIL) {
+
+    funcexe_T funcexe = FUNCEXE_INIT;
+    funcexe.firstline = eap->line1;
+    funcexe.lastline = eap->line2;
+    funcexe.doesrange = &doesrange;
+    funcexe.evaluate = true;
+    funcexe.partial = partial;
+    funcexe.selfdict = fudi.fd_dict;
+    if (get_func_tv(name, -1, &rettv, &arg, &funcexe) == FAIL) {
       failed = true;
       break;
     }
 
     // Handle a function returning a Funcref, Dictionary or List.
-    if (handle_subscript((const char **)&arg, &rettv, true, true)
+    if (handle_subscript((const char **)&arg, &rettv, true, true,
+                         (const char_u *)name, (const char_u **)&name)
         == FAIL) {
       failed = true;
       break;
diff --git a/src/nvim/eval/userfunc.h b/src/nvim/eval/userfunc.h
index e8ad0bf1da..3f111343d2 100644
--- a/src/nvim/eval/userfunc.h
+++ b/src/nvim/eval/userfunc.h
@@ -28,11 +28,37 @@ typedef enum {
   ERROR_OTHER,
   ERROR_BOTH,
   ERROR_DELETED,
+  ERROR_NOTMETHOD,
 } FnameTransError;
 
+/// Used in funcexe_T. Returns the new argcount.
 typedef int (*ArgvFunc)(int current_argcount, typval_T *argv, int argskip,
                         int called_func_argcount);
 
+/// Structure passed between functions dealing with function call execution.
+typedef struct {
+  ArgvFunc argv_func;  ///< when not NULL, can be used to fill in arguments only
+                       ///< when the invoked function uses them
+  linenr_T firstline;  ///< first line of range
+  linenr_T lastline;   ///< last line of range
+  bool *doesrange;     ///< [out] if not NULL: function handled range
+  bool evaluate;       ///< actually evaluate expressions
+  partial_T *partial;  ///< for extra arguments
+  dict_T *selfdict;    ///< Dictionary for "self"
+  typval_T *basetv;    ///< base for base->method()
+} funcexe_T;
+
+#define FUNCEXE_INIT (funcexe_T) { \
+  .argv_func = NULL, \
+  .firstline = 0, \
+  .lastline = 0, \
+  .doesrange = NULL, \
+  .evaluate = false, \
+  .partial = NULL, \
+  .selfdict = NULL, \
+  .basetv = NULL, \
+}
+
 #define FUNCARG(fp, j)  ((char_u **)(fp->uf_args.ga_data))[j]
 #define FUNCLINE(fp, j) ((char_u **)(fp->uf_lines.ga_data))[j]