Merge pull request #12954 from s-hadinger/berry_vararg

Berry support for vararg

CHANGELOG.md

@@ -7,6 +7,7 @@ All notable changes to this project will be documented in this file.
 ### Added
 - Turn HTTP API (command ``SetOption128 1``) default on for backward compatibility
 - Support for IEM3155 Wattmeter (#12940)
+- Berry support for vararg
 
 ### Fixed
 - WDT reset on shutters with stepper motors during deceleration (#12849)

lib/libesp32/Berry/src/be_parser.c

@@ -528,23 +528,45 @@ static void singlevar(bparser *parser, bexpdesc *var)
     }
 }
 
+/* parse a vararg argument in the form `def f(a, *b) end` */
+/* Munch the '*', read the token, create variable and declare the function as vararg */
+static void func_vararg(bparser *parser) {
+    bexpdesc v;
+    bstring *str;
+    match_token(parser, OptMul); /* skip '*' */
+    str = next_token(parser).u.s;
+    match_token(parser, TokenId); /* match and skip ID */
+    new_var(parser, str, &v); /* new variable */
+    parser->finfo->proto->varg = 1;   /* set varg flag */
+}
+
 /* Parse function or method definition variable list */
 /* Create an implicit local variable for each argument starting at R0 */
 /* Update function proto argc to the expected number or arguments */
 /* Raise an exception if multiple arguments have the same name */
+/* New: vararg support */
 static void func_varlist(bparser *parser)
 {
     bexpdesc v;
     bstring *str;
-    /* '(' [ID {',' ID}] ')' */
+    /* '(' [ ID {',' ID}] ')' or */
+    /* '(' '*' ID ')' or */
+    /* '(' [ ID {',' ID}] ',' '*' ID ')' */
     match_token(parser, OptLBK); /* skip '(' */
-    if (match_id(parser, str) != NULL) {
+    if (next_type(parser) == OptMul) {
+        func_vararg(parser);
+    } else if (match_id(parser, str) != NULL) {
         new_var(parser, str, &v); /* new variable */
         while (match_skip(parser, OptComma)) { /* ',' */
-            str = next_token(parser).u.s;
-            match_token(parser, TokenId); /* match and skip ID */
-            /* new local variable */
-            new_var(parser, str, &v);
+            if (next_type(parser) == OptMul) {
+                func_vararg(parser);
+                break;
+            } else {
+                str = next_token(parser).u.s;
+                match_token(parser, TokenId); /* match and skip ID */
+                /* new local variable */
+                new_var(parser, str, &v);
+            }
         }
     }
     match_token(parser, OptRBK); /* skip ')' */

lib/libesp32/Berry/src/be_vm.c

@@ -12,6 +12,7 @@
 #include "be_class.h"
 #include "be_func.h"
 #include "be_vector.h"
+#include "be_list.h"
 #include "be_map.h"
 #include "be_module.h"
 #include "be_mem.h"
@@ -1086,6 +1087,20 @@ newframe: /* a new call frame */
                 for (; v < end; ++v) {  /* set all not provided arguments to nil */
                     var_setnil(v);
                 }
+                if (proto->varg) {  /* there are vararg at the last argument, build the list */
+                    /* code below uses mostly low-level calls for performance */
+                    be_stack_require(vm, argc + 2);   /* make sure we don't overflow the stack */
+                    bvalue *top_save = vm->top;  /* save original stack, we need fresh slots to create the 'list' instance */
+                    vm->top = v;  /* move top of stack right after last argument */
+                    be_newobject(vm, "list");  /* this creates 2 objects on stack: list instance, BE_LIST object */
+                    blist *list = var_toobj(vm->top-1);  /* get low-level BE_LIST structure */
+                    v = reg + proto->argc - 1;  /* last argument */
+                    for (; v < reg + argc; v++) {
+                        be_list_push(vm, list, v); /* push all varargs into list */       
+                    }
+                    *(reg + proto->argc - 1) = *(vm->top-2);  /* change the vararg argument to now contain the list instance */
+                    vm->top = top_save;  /* restore top of stack pointer */
+                }
                 goto newframe;  /* continue execution of the closure */
             }
             case BE_NTVCLOS: {

lib/libesp32/Berry/tests/vararg.be

@@ -0,0 +1,14 @@
+#- vararg -#
+def f(a,*b) return b end
+
+assert(f() == [])
+assert(f(1) == [])
+assert(f(1,2) == [2])
+assert(f(1,2,3) == [2, 3])
+
+def g(*a) return a end
+
+assert(g() == [])
+assert(g("foo") == ["foo"])
+assert(g("foo", nil) == ["foo", nil])
+assert(g("foo", nil, 2) == ["foo", nil, 2])

tasmota/xdrv_52_9_berry.ino

@@ -347,7 +347,7 @@ void BrLoad(const char * script_name) {
     bool loaded = be_tobool(berry.vm, -2);  // did it succeed?
     be_pop(berry.vm, 2);
     if (loaded) {
-      AddLog(LOG_LEVEL_INFO, D_LOG_BERRY "sucessfully loaded '%s'", script_name);
+      AddLog(LOG_LEVEL_INFO, D_LOG_BERRY "successfully loaded '%s'", script_name);
     } else {
       AddLog(LOG_LEVEL_INFO, D_LOG_BERRY "no '%s'", script_name);
     }