vim-patch:8.2.{0695,0725,0734,0753,0818,0819,0822} (#23075)

vim-patch:8.2.0695: Vim9: cannot define a function inside a function

Problem:    Vim9: cannot define a function inside a function.
Solution:   Initial support for :def inside :def.

https://github.com/vim/vim/commit/04b12697838b232b8b17c553ccc74cf1f1bdb81c

vim-patch:8.2.0725: Vim9: cannot call a function declared later in Vim9 script

Problem:    Vim9: cannot call a function declared later in Vim9 script.
Solution:   Make two passes through the script file.

https://github.com/vim/vim/commit/09689a02840be40fa7bb10b1921fb5bc5b2908f1

vim-patch:8.2.0734: Vim9: leaking memory when using :finish

Problem:    Vim9: leaking memory when using :finish.
Solution:   Do not check for next line in third pass.

https://github.com/vim/vim/commit/04816717dfea6e2469ff4c9d40f68b59aaf03724

vim-patch:8.2.0753: Vim9: expressions are evaluated in the discovery phase

Problem:    Vim9: expressions are evaluated in the discovery phase.
Solution:   Bail out if an expression is not a constant.  Require a type for
            declared constants.

https://github.com/vim/vim/commit/32e351179eacfc84f64cd5029e221582d400bb38

vim-patch:8.2.0818: Vim9: using a discovery phase doesn't work well

Problem:    Vim9: using a discovery phase doesn't work well.
Solution:   Remove the discovery phase, instead compile a function only when
            it is used.  Add :defcompile to compile def functions earlier.

https://github.com/vim/vim/commit/822ba24743af9ee1b5e7f656a7a61a38f3638bca

vim-patch:8.2.0819: compiler warning for unused variable

Problem:    Compiler warning for unused variable.
Solution:   Remove the variable.

https://github.com/vim/vim/commit/f40e51a880a95f94dbbbecc9476559506c2cc345

vim-patch:8.2.0822: Vim9: code left over from discovery phase

Problem:    Vim9: code left over from discovery phase.
Solution:   Remove the dead code.

https://github.com/vim/vim/commit/2eec37926db6d31beb36f162ac00357a30c093c8

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

3 files changed, 22 insertions, 24 deletions

diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index 7f224f371c..52e38b73ba 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -1550,7 +1550,7 @@ static void f_eval(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   const char *const expr_start = s;
-  if (s == NULL || eval1((char **)&s, rettv, true) == FAIL) {
+  if (s == NULL || eval1((char **)&s, rettv, EVAL_EVALUATE) == FAIL) {
     if (expr_start != NULL && !aborting()) {
       semsg(_(e_invexpr2), expr_start);
     }
diff --git a/src/nvim/eval/userfunc.c b/src/nvim/eval/userfunc.c
index f09da6b79b..f82ab08d2d 100644
--- a/src/nvim/eval/userfunc.c
+++ b/src/nvim/eval/userfunc.c
@@ -152,7 +152,7 @@ static int get_function_args(char **argp, char endchar, garray_T *newargs, int *
         p = skipwhite(p) + 1;
         p = skipwhite(p);
         char *expr = p;
-        if (eval1(&p, &rettv, false) != FAIL) {
+        if (eval1(&p, &rettv, 0) != FAIL) {
           ga_grow(default_args, 1);
 
           // trim trailing whitespace
@@ -463,7 +463,8 @@ int get_func_tv(const char *name, int len, typval_T *rettv, char **arg, funcexe_
     if (*argp == ')' || *argp == ',' || *argp == NUL) {
       break;
     }
-    if (eval1(&argp, &argvars[argcount], funcexe->fe_evaluate) == FAIL) {
+    if (eval1(&argp, &argvars[argcount],
+              funcexe->fe_evaluate ? EVAL_EVALUATE : 0) == FAIL) {
       ret = FAIL;
       break;
     }
@@ -972,7 +973,7 @@ void call_user_func(ufunc_T *fp, int argcount, typval_T *argvars, typval_T *rett
 
         default_expr = ((char **)(fp->uf_def_args.ga_data))
                        [ai + fp->uf_def_args.ga_len];
-        if (eval1(&default_expr, &def_rettv, true) == FAIL) {
+        if (eval1(&default_expr, &def_rettv, EVAL_EVALUATE) == FAIL) {
           default_arg_err = true;
           break;
         }
@@ -1109,7 +1110,7 @@ void call_user_func(ufunc_T *fp, int argcount, typval_T *argvars, typval_T *rett
     // A Lambda always has the command "return {expr}".  It is much faster
     // to evaluate {expr} directly.
     ex_nesting_level++;
-    (void)eval1(&p, rettv, true);
+    (void)eval1(&p, rettv, EVAL_EVALUATE);
     ex_nesting_level--;
   } else {
     // call do_cmdline() to execute the lines
@@ -2953,7 +2954,7 @@ void ex_return(exarg_T *eap)
 
   eap->nextcmd = NULL;
   if ((*arg != NUL && *arg != '|' && *arg != '\n')
-      && eval0(arg, &rettv, &eap->nextcmd, !eap->skip) != FAIL) {
+      && eval0(arg, &rettv, &eap->nextcmd, eap->skip ? 0 : EVAL_EVALUATE) != FAIL) {
     if (!eap->skip) {
       returning = do_return(eap, false, true, &rettv);
     } else {
@@ -3004,7 +3005,7 @@ void ex_call(exarg_T *eap)
     // instead to skip to any following command, e.g. for:
     //   :if 0 | call dict.foo().bar() | endif.
     emsg_skip++;
-    if (eval0(eap->arg, &rettv, &eap->nextcmd, false) != FAIL) {
+    if (eval0(eap->arg, &rettv, &eap->nextcmd, 0) != FAIL) {
       tv_clear(&rettv);
     }
     emsg_skip--;
@@ -3071,7 +3072,7 @@ void ex_call(exarg_T *eap)
     }
 
     // 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, EVAL_EVALUATE, true)
         == FAIL) {
       failed = true;
       break;
diff --git a/src/nvim/eval/vars.c b/src/nvim/eval/vars.c
index 9120cc4471..a3dc0cfc04 100644
--- a/src/nvim/eval/vars.c
+++ b/src/nvim/eval/vars.c
@@ -175,21 +175,13 @@ static list_T *heredoc_get(exarg_T *eap, char *cmd)
 /// ":let var ..= expr" assignment command.
 /// ":let [var1, var2] = expr" unpack list.
 /// ":let [name, ..., ; lastname] = expr" unpack list.
-void ex_let(exarg_T *eap)
-{
-  ex_let_const(eap, false);
-}
-
+///
 /// ":cons[t] var = expr1" define constant
 /// ":cons[t] [name1, name2, ...] = expr1" define constants unpacking list
 /// ":cons[t] [name, ..., ; lastname] = expr" define constants unpacking list
-void ex_const(exarg_T *eap)
-{
-  ex_let_const(eap, true);
-}
-
-static void ex_let_const(exarg_T *eap, const bool is_const)
+void ex_let(exarg_T *eap)
 {
+  const bool is_const = eap->cmdidx == CMD_const;
   char *arg = eap->arg;
   char *expr = NULL;
   typval_T rettv;
@@ -208,8 +200,10 @@ static void ex_let_const(exarg_T *eap, const bool is_const)
     argend--;
   }
   expr = skipwhite(argend);
-  if (*expr != '=' && !((vim_strchr("+-*/%.", (uint8_t)(*expr)) != NULL
-                         && expr[1] == '=') || strncmp(expr, "..=", 3) == 0)) {
+  bool concat = strncmp(expr, "..=", 3) == 0;
+  bool has_assign = *expr == '=' || (vim_strchr("+-*/%.", (uint8_t)(*expr)) != NULL
+                                     && expr[1] == '=');
+  if (!has_assign && !concat) {
     // ":let" without "=": list variables
     if (*arg == '[') {
       emsg(_(e_invarg));
@@ -240,6 +234,8 @@ static void ex_let_const(exarg_T *eap, const bool is_const)
       tv_clear(&rettv);
     }
   } else {
+    rettv.v_type = VAR_UNKNOWN;
+
     op[0] = '=';
     op[1] = NUL;
     if (*expr != '=') {
@@ -259,7 +255,8 @@ static void ex_let_const(exarg_T *eap, const bool is_const)
     if (eap->skip) {
       emsg_skip++;
     }
-    i = eval0(expr, &rettv, &eap->nextcmd, !eap->skip);
+    int eval_flags = eap->skip ? 0 : EVAL_EVALUATE;
+    i = eval0(expr, &rettv, &eap->nextcmd, eval_flags);
     if (eap->skip) {
       if (i != FAIL) {
         tv_clear(&rettv);
@@ -506,7 +503,7 @@ static const char *list_arg_vars(exarg_T *eap, const char *arg, int *first)
         } else {
           // handle d.key, l[idx], f(expr)
           const char *const arg_subsc = arg;
-          if (handle_subscript(&arg, &tv, true, true) == FAIL) {
+          if (handle_subscript(&arg, &tv, EVAL_EVALUATE, true) == FAIL) {
             error = true;
           } else {
             if (arg == arg_subsc && len == 2 && name[1] == ':') {
@@ -1713,7 +1710,7 @@ bool var_exists(const char *var)
     n = get_var_tv(name, len, &tv, NULL, false, true) == OK;
     if (n) {
       // Handle d.key, l[idx], f(expr).
-      n = handle_subscript(&var, &tv, true, false) == OK;
+      n = handle_subscript(&var, &tv, EVAL_EVALUATE, false) == OK;
       if (n) {
         tv_clear(&tv);
       }