Initial implementation of arbitrary expression interpolation

Author: tpunt

Zend/tests/arbitrary_expression_interpolation.phpt

@@ -0,0 +1,18 @@
+--TEST--
+Arbitrary expression interpolation
+--FILE--
+<?php
+
+function a() {return "d";}
+$value = 10;
+
+var_dump(
+	"Result: #{$value * 5}",
+	"abc#{(function(){return "def";})()}",
+	"abc#{a()}"
+);
+?>
+--EXPECT--	
+string(10) "Result: 50"
+string(6) "abcdef"
+string(6) "abcd"

Zend/zend_ast.c

@@ -772,7 +772,10 @@ static void zend_ast_export_encaps_list(smart_str *str, char quote, zend_ast_lis
 		if (ast->kind == ZEND_AST_ZVAL) {
 			zval *zv = zend_ast_get_zval(ast);
 
-			ZEND_ASSERT(Z_TYPE_P(zv) == IS_STRING);
+			if (Z_TYPE_P(zv) != IS_STRING) {
+				convert_to_string(zv);
+			}
+
 			zend_ast_export_qstr(str, quote, Z_STR_P(zv));
 		} else if (ast->kind == ZEND_AST_VAR &&
 		           ast->child[0]->kind == ZEND_AST_ZVAL &&