patch 8.2.2635: Vim9: cannot define an inline function

Problem:    Vim9: cannot define an inline function.
Solution:   Make an inline function mostly work.

Author: brammool

src/errors.h

@@ -377,3 +377,7 @@ EXTERN char e_import_as_name_not_supported_here[]
 	INIT(= N_("E1169: 'import * as {name}' not supported here"));
 EXTERN char e_cannot_use_hash_curly_to_start_comment[]
 	INIT(= N_("E1170: Cannot use #{ to start a comment"));
+EXTERN char e_missing_end_block[]
+	INIT(= N_("E1171: Missing } after inline function"));
+EXTERN char e_cannot_use_default_values_in_lambda[]
+	INIT(= N_("E1172: Cannot use default values in a lambda"));

src/misc2.c

@@ -2026,8 +2026,9 @@ ga_clear_strings(garray_T *gap)
 {
     int		i;
 
-    for (i = 0; i < gap->ga_len; ++i)
-	vim_free(((char_u **)(gap->ga_data))[i]);
+    if (gap->ga_data != NULL)
+	for (i = 0; i < gap->ga_len; ++i)
+	    vim_free(((char_u **)(gap->ga_data))[i]);
     ga_clear(gap);
 }
 

src/proto/vim9compile.pro

@@ -14,6 +14,7 @@ char_u *to_name_end(char_u *arg, int use_namespace);
 char_u *to_name_const_end(char_u *arg);
 exprtype_T get_compare_type(char_u *p, int *len, int *type_is);
 void error_white_both(char_u *op, int len);
+void fill_exarg_from_cctx(exarg_T *eap, cctx_T *cctx);
 int assignment_len(char_u *p, int *heredoc);
 void vim9_declare_error(char_u *name);
 int check_vim9_unlet(char_u *name);

src/testdir/test_vim9_expr.vim

@@ -1946,6 +1946,25 @@ def Test_expr7_lambda()
   CheckScriptSuccess(lines)
 enddef
 
+def Test_expr7_lambda_block()
+  var lines =<< trim END
+      var Func = (s: string): string => {
+                      return 'hello ' .. s
+                    }
+      assert_equal('hello there', Func('there'))
+
+      var ll = range(3)
+      var dll = mapnew(ll, (k, v): string => {
+          if v % 2
+            return 'yes'
+          endif
+          return 'no'
+        })
+      assert_equal(['no', 'yes', 'no'], dll)
+  END
+  CheckDefAndScriptSuccess(lines)
+enddef
+
 def NewLambdaWithComments(): func
   return (x) =>
             # some comment