fix closure assertions related to outer_var_env==outer_lex_env, which is not the case

src/duk_builtin_function.c

@@ -59,6 +59,10 @@ int duk_builtin_function_constructor(duk_context *ctx) {
 	DUK_ASSERT(func != NULL);
 	DUK_ASSERT(DUK_HOBJECT_IS_COMPILEDFUNCTION((duk_hobject *) func));
 
+	/* only outer_lex_env matters, as functions always get a new
+	 * variable declaration environment.
+	 */
+
 	outer_lex_env = thr->builtins[DUK_BIDX_GLOBAL_ENV];
 	outer_var_env = thr->builtins[DUK_BIDX_GLOBAL_ENV];
 

src/duk_js_executor.c

@@ -1972,6 +1972,10 @@ void duk_js_execute_bytecode(duk_hthread *entry_thread) {
 			DUK_ASSERT(act->var_env != NULL);
 			DUK_ASSERT(act->lex_env != NULL);
 
+			/* functions always have a NEWENV flag, i.e. they get a
+			 * new variable declaration environment, so only lex_env
+			 * matters here.
+			 */
 			duk_js_push_closure(thr,
 			                    (duk_hcompiledfunction *) fun_temp,
 			                    act->var_env,

src/duk_js_var.c

@@ -98,6 +98,13 @@ static void increase_data_inner_refcounts(duk_hthread *thr, duk_hcompiledfunctio
 	}
 }
 
+/* Push a new closure on the stack.
+ *
+ * Note: if fun_temp has NEWENV, i.e. a new lexical and variable
+ * declaration is created when the function is called, only
+ * outer_lex_env matters (outer_var_env is ignored and may or
+ * may not be same as outer_lex_env).
+ */
 void duk_js_push_closure(duk_hthread *thr,
                          duk_hcompiledfunction *fun_temp,
                          duk_hobject *outer_var_env,
@@ -207,17 +214,14 @@ void duk_js_push_closure(duk_hthread *thr,
 			 *  in an intermediate environment record.  The "outer"
 			 *  lexical/variable environment will thus be:
 			 *
-			 *  a) { funcname: <func>, _prototype: outer_var_env }
-			 *  b) { funcname: <func>, _prototype:  <globalenv> }  (if outer_var_env missing)
-			 *
-			 *  For named function expressions outer_var_env == outer_lex_env.
+			 *  a) { funcname: <func>, _prototype: outer_lex_env }
+			 *  b) { funcname: <func>, _prototype:  <globalenv> }  (if outer_lex_env missing)
 			 */
 
-			DUK_ASSERT(outer_var_env == outer_lex_env);
 			DUK_ASSERT(duk_has_prop_stridx(ctx, -1, DUK_STRIDX_NAME));  /* required if NAMEBINDING set */
 
-			if (outer_var_env) {
-				proto = outer_var_env;
+			if (outer_lex_env) {
+				proto = outer_lex_env;
 			} else {
 				proto = thr->builtins[DUK_BIDX_GLOBAL_ENV];
 			}
@@ -240,7 +244,9 @@ void duk_js_push_closure(duk_hthread *thr,
 			/* [ ... closure template env ] */
 
 			duk_def_prop_stridx(ctx, -3, DUK_STRIDX_INT_LEXENV, DUK_PROPDESC_FLAGS_WC);
-			/* since outer_var_env == outer_lex_env, never define DUK_STRIDX_INT_VARENV */
+			/* since closure has NEWENV, never define DUK_STRIDX_INT_VARENV, as it
+			 * will be ignored anyway
+			 */
 
 			/* [ ... closure template ] */
 		} else {
@@ -248,16 +254,13 @@ void duk_js_push_closure(duk_hthread *thr,
 			 *  Other cases (function declaration, anonymous function expression,
 			 *  strict direct eval code).  The "outer" environment will be whatever
 			 *  the caller gave us.
-			 *
-			 *  Here, too, outer_var_env == outer_lex_env.
 			 */
 
-			/* FIXME: code is same as !NEWENV code below; also, varenv == lexenv always? */
-
-			DUK_ASSERT(outer_var_env == outer_lex_env);
-
 			duk_push_hobject(ctx, outer_lex_env);  /* -> [ ... closure template env ] */
 			duk_def_prop_stridx(ctx, -3, DUK_STRIDX_INT_LEXENV, DUK_PROPDESC_FLAGS_WC);
+			/* since closure has NEWENV, never define DUK_STRIDX_INT_VARENV, as it
+			 * will be ignored anyway
+			 */
 
 			/* [ ... closure template ] */
 		}