[RFC] Deprecate ${} string interpolation

Zend/tests/bug61681.phpt

@@ -7,5 +7,6 @@ $la = "ooxx";
 echo "${substr('laruence', 0, 2)}";
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 ooxx

Zend/tests/deprecate_dollar_brace_string_interpolation_1.phpt

@@ -0,0 +1,12 @@
+--TEST--
+"${}" emits a deprecation
+--FILE--
+<?php
+
+$foo = 'bar';
+var_dump("${foo}");
+
+?>
+--EXPECTF--
+Deprecated: Using ${var} in strings is deprecated, use {$var} instead in %s on line %d
+string(3) "bar"

Zend/tests/exception_in_nested_rope.phpt

@@ -13,5 +13,6 @@ try {
 }
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 Exception

Zend/tests/flexible-heredoc-complex-test1.phpt

@@ -21,7 +21,10 @@ var_dump(<<<DOC1
     DOC1);
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
+
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 string(5) "a
 b
 c"

Zend/tests/flexible-heredoc-complex-test2.phpt

@@ -21,7 +21,10 @@ var_dump(<<<DOC1
     DOC1);
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
+
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 string(5) "a
 b
 c"

Zend/tests/flexible-heredoc-complex-test3.phpt

@@ -21,7 +21,10 @@ var_dump(<<<DOC1
     DOC1);
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
+
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 string(8) "  a
  b
 c"

Zend/tests/flexible-heredoc-complex-test4.phpt

@@ -28,7 +28,10 @@ the same delimiter name as the heredoc
 }
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
+
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 string(8) "Test
 FOO"
 string(16) "    Test

Zend/tests/temporary_cleaning_016.phpt

@@ -11,5 +11,6 @@ try {
 }
 ?>
 DONE
---EXPECT--
+--EXPECTF--
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
 DONE

Zend/tests/warning_during_heredoc_scan_ahead.phpt

@@ -14,4 +14,6 @@ Warning: Octal escape sequence overflow \400 is greater than \377 in %s on line
 
 Warning: Octal escape sequence overflow \400 is greater than \377 in %s on line %d
 
+Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in %s on line %d
+
 Warning: Undefined variable $ in %s on line %d

Zend/zend_compile.c

@@ -9504,7 +9504,16 @@ static void zend_compile_encaps_list(znode *result, zend_ast *ast) /* {{{ */
 	j = 0;
 	last_const_node.op_type = IS_UNUSED;
 	for (i = 0; i < list->children; i++) {
-		zend_compile_expr(&elem_node, list->child[i]);
+		zend_ast *encaps_var = list->child[i];
+		if (encaps_var->attr & (ZEND_ENCAPS_VAR_DOLLAR_CURLY|ZEND_ENCAPS_VAR_DOLLAR_CURLY_VAR_VAR)) {
+			if (encaps_var->attr & ZEND_ENCAPS_VAR_DOLLAR_CURLY_VAR_VAR) {
+				zend_error(E_DEPRECATED, "Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead");
+			} else {
+				zend_error(E_DEPRECATED, "Using ${var} in strings is deprecated, use {$var} instead");
+			}
+		}
+
+		zend_compile_expr(&elem_node, encaps_var);
 
 		if (elem_node.op_type == IS_CONST) {
 			convert_to_string(&elem_node.u.constant);

Zend/zend_compile.h

@@ -1077,6 +1077,10 @@ static zend_always_inline bool zend_check_arg_send_type(const zend_function *zf,
 /* Attribute for ternary inside parentheses */
 #define ZEND_PARENTHESIZED_CONDITIONAL 1
 
+/* Attributes for ${} encaps var in strings */
+#define ZEND_ENCAPS_VAR_DOLLAR_CURLY (1<<0)
+#define ZEND_ENCAPS_VAR_DOLLAR_CURLY_VAR_VAR (1<<1)
+
 /* For "use" AST nodes and the seen symbol table */
 #define ZEND_SYMBOL_CLASS    (1<<0)
 #define ZEND_SYMBOL_FUNCTION (1<<1)

Zend/zend_language_parser.y

@@ -1490,11 +1490,11 @@ encaps_var:
 			{ $$ = zend_ast_create(ZEND_AST_NULLSAFE_PROP,
 			      zend_ast_create(ZEND_AST_VAR, $1), $3); }
 	|	T_DOLLAR_OPEN_CURLY_BRACES expr '}'
-			{ $$ = zend_ast_create(ZEND_AST_VAR, $2); }
+			{ $$ = zend_ast_create_ex(ZEND_AST_VAR, ZEND_ENCAPS_VAR_DOLLAR_CURLY_VAR_VAR, $2); }
 	|	T_DOLLAR_OPEN_CURLY_BRACES T_STRING_VARNAME '}'
-			{ $$ = zend_ast_create(ZEND_AST_VAR, $2); }
+			{ $$ = zend_ast_create_ex(ZEND_AST_VAR, ZEND_ENCAPS_VAR_DOLLAR_CURLY, $2); }
 	|	T_DOLLAR_OPEN_CURLY_BRACES T_STRING_VARNAME '[' expr ']' '}'
-			{ $$ = zend_ast_create(ZEND_AST_DIM,
+			{ $$ = zend_ast_create_ex(ZEND_AST_DIM, ZEND_ENCAPS_VAR_DOLLAR_CURLY,
 			      zend_ast_create(ZEND_AST_VAR, $2), $4); }
 	|	T_CURLY_OPEN variable '}' { $$ = $2; }
 ;

Zend/zend_vm_gen.php

@@ -2865,7 +2865,7 @@ function gen_vm($def, $skel) {
                             out($f, "\t\t\t\t\tbreak;\n");
                             out($f, "\t\t\t\t}\n");
                         }
-                        out($f, "\t\t\t\tspec = ${spec_dsc['spec_code']};\n");
+                        out($f, "\t\t\t\tspec = {$spec_dsc['spec_code']};\n");
                         if (isset($spec_dsc["spec"]["COMMUTATIVE"]) && !isset($dsc["spec"]["COMMUTATIVE"])) {
                             out($f, "\t\t\t\tif (op->op1_type < op->op2_type) {\n");
                             out($f, "\t\t\t\t\tzend_swap_operands(op);\n");

build/gen_stub.php

@@ -1484,7 +1484,7 @@ public function getDeclaration(): string {
                 } else {
                     $escapedClassName = $arginfoType->classTypes[0]->toEscapedName();
                     $varEscapedClassName = $arginfoType->classTypes[0]->toVarEscapedName();
-                    $code .= "\tzend_string *property_{$propertyName}_class_{$varEscapedClassName} = zend_string_init(\"{$escapedClassName}\", sizeof(\"${escapedClassName}\")-1, 1);\n";
+                    $code .= "\tzend_string *property_{$propertyName}_class_{$varEscapedClassName} = zend_string_init(\"{$escapedClassName}\", sizeof(\"{$escapedClassName}\")-1, 1);\n";
 
                     $typeCode = "(zend_type) ZEND_TYPE_INIT_CLASS(property_{$propertyName}_class_{$varEscapedClassName}, 0, " . $arginfoType->toTypeMask() . ")";
                 }

ext/oci8/tests/lob_prefetch.phpt

@@ -35,7 +35,7 @@ $ora_sql =
       end loop;
       dbms_lob.createtemporary(b, false);
       dbms_lob.converttoblob(b, c, dbms_lob.lobmaxsize, dest_offset, src_offset, dbms_lob.default_csid, ctx, warn);
-      insert /*+ APPEND */ into ${schema}${table_name} (id, clob, blob) values (j, c, b);
+      insert /*+ APPEND */ into {$schema}{$table_name} (id, clob, blob) values (j, c, b);
     end loop;
     commit;
   end;";
@@ -119,7 +119,7 @@ try {
 
 print("Test 3 - CLOB prefetch_lob_size 100000\n");
 
-$sql = "select clob from ${schema}${table_name}" . " order by id";
+$sql = "select clob from {$schema}{$table_name}" . " order by id";
 $locarr = get_clob_loc($c, $sql, 100000);
 $inlinearr = get_clob_inline($c, $sql, 100000);
 
@@ -138,7 +138,7 @@ check_clobs($locarr, $inlinearr);
 
 print("Test 4 - BLOB prefetch_lob_size 100000\n");
 
-$sql = "select blob from ${schema}${table_name}" . " order by id";
+$sql = "select blob from {$schema}{$table_name}" . " order by id";
 $locarr = get_blob_loc($c, $sql, 100000);
 
 print(count($locarr) . "\n");

ext/oci8/tests/lob_prefetch_ini.phpt

@@ -37,7 +37,7 @@ $ora_sql =
       end loop;
       dbms_lob.createtemporary(b, false);
       dbms_lob.converttoblob(b, c, dbms_lob.lobmaxsize, dest_offset, src_offset, dbms_lob.default_csid, ctx, warn);
-      insert /*+ APPEND */ into ${schema}${table_name} (id, clob, blob) values (j, c, b);
+      insert /*+ APPEND */ into {$schema}{$table_name} (id, clob, blob) values (j, c, b);
     end loop;
     commit;
   end;";
@@ -108,7 +108,7 @@ var_dump($r);
 
 print("Test 2 - CLOB with current oci8.prefetch_lob_size\n");
 
-$sql = "select clob from ${schema}${table_name}" . " order by id";
+$sql = "select clob from {$schema}{$table_name}" . " order by id";
 $locarr = get_clob_loc($c, $sql, -1);
 $inlinearr = get_clob_inline($c, $sql, -1);
 
@@ -136,7 +136,7 @@ check_clobs($locarr, $inlinearr);
 
 print("Test 5 - BLOB with current ocig8.prefetch_lob_size \n");
 
-$sql = "select blob from ${schema}${table_name}" . " order by id";
+$sql = "select blob from {$schema}{$table_name}" . " order by id";
 $locarr = get_blob_loc($c, $sql, -1);
 
 print(count($locarr) . "\n");

ext/opcache/tests/opt/gh8140a.phpt

@@ -5,7 +5,7 @@ GH-8140 (Wrong first class callable by name optimization)
 namespace Test;
 
 function greeter(string $name) {
-  echo "Hello, ${name}!";
+  echo "Hello, {$name}!";
 }
 
 $mycallable = greeter(...);

ext/opcache/tests/opt/gh8140b.phpt

@@ -5,7 +5,7 @@ GH-8140 (Wrong first class callable by name optimization)
 $mycallable = greeter(...);
 
 function greeter(string $name) {
-    echo "Hello, ${name}!";
+    echo "Hello, {$name}!";
 }
 
 $mycallable("world");

ext/pgsql/tests/config.inc

@@ -16,8 +16,8 @@ $view_name   = "php_pgsql_viewtest";
 $view_def    = "CREATE VIEW {$view_name} AS SELECT * FROM {$table_name};";
 
 // Test table
-$table_def    = "CREATE TABLE ${table_name} (num int, str text, bin bytea);";
-$table_def_92 = "CREATE TABLE ${table_name_92} (textary text[],  jsn json);";
+$table_def    = "CREATE TABLE {$table_name} (num int, str text, bin bytea);";
+$table_def_92 = "CREATE TABLE {$table_name_92} (textary text[],  jsn json);";
 $field_name = "num";             // For pg_field_num()
 
 ?>

ext/phar/phar/clicommand.inc

@@ -30,9 +30,9 @@ abstract class CLICommand
         $this->typs = self::getArgTyps($this);
 
         if ($argc < 2) {
-            self::error("No command given, check ${argv[0]} help\n");
+            self::error("No command given, check {$argv[0]} help\n");
         } elseif (!isset($this->cmds[$argv[1]]['run'])) {
-            self::error("Unknown command '${argv[1]}', check ${argv[0]} help\n");
+            self::error("Unknown command '{$argv[1]}', check {$argv[0]} help\n");
         } else {
             $command = $argv[1];
         }
@@ -46,12 +46,12 @@ abstract class CLICommand
                     if (strlen($argv[$i]) == 2 && isset($this->args[$argv[$i][1]])) {
                         $arg = $argv[$i][1];
                         if (++$i >= $argc) {
-                            self::error("Missing argument to parameter '$arg' of command '$command', check ${argv[0]} help\n");
+                            self::error("Missing argument to parameter '$arg' of command '$command', check {$argv[0]} help\n");
                         } else {
                             $this->args[$arg]['val'] = $this->checkArgTyp($arg, $i, $argc, $argv);
                         }
                     }  else {
-                        self::error("Unknown parameter '${argv[$i]}' to command $command, check ${argv[0]} help\n");
+                        self::error("Unknown parameter '{$argv[$i]}' to command $command, check {$argv[0]} help\n");
                     }
                 } else {
                     break;
@@ -61,7 +61,7 @@ abstract class CLICommand
             if (isset($this->args[''])) {
                 if ($i >= $argc) {
                     if (isset($this->args['']['require']) && $this->args['']['require']) {
-                        self::error("Missing default trailing arguments to command $command, check ${argv[0]} help\n");
+                        self::error("Missing default trailing arguments to command $command, check {$argv[0]} help\n");
                     }
                 } else {
                     $this->args['']['val'] = array();
@@ -70,12 +70,12 @@ abstract class CLICommand
                     }
                 }
             } else if ($i < $argc) {
-                self::error("Unexpected default arguments to command $command, check ${argv[0]} help\n");
+                self::error("Unexpected default arguments to command $command, check {$argv[0]} help\n");
             }
 
             foreach($this->args as $arg => $inf) {
                 if (strlen($arg) && !isset($inf['val']) && isset($inf['required']) && $inf['required']) {
-                    $missing .=  "Missing parameter '-$arg' to command $command, check ${argv[0]} help\n";
+                    $missing .=  "Missing parameter '-$arg' to command $command, check {$argv[0]} help\n";
                 }
             }
 
@@ -265,7 +265,7 @@ abstract class CLICommand
                 $sp3 = $this->cli_get_SP3($l, $ls, $inf);
                 $l3  = strlen($sp3);
                 foreach($conf['select'] as $opt => $what) {
-                    $inf .= $this->cli_wordwrap($sp2 . "  " . sprintf("%-${ls}s  ", $opt) . $what, $l3, $sp3) . "\n";
+                    $inf .= $this->cli_wordwrap($sp2 . "  " . sprintf("%-{$ls}s  ", $opt) . $what, $l3, $sp3) . "\n";
                 }
             }
         }

ext/phar/phar/pharcommand.inc

@@ -1598,7 +1598,7 @@ class PharCommand extends CLICommand
             if (is_bool($v)) {
                 $v = $v ? 'enabled' : 'disabled';
             }
-            printf("%-${klen}s  %s\n", $k.':', $v);
+            printf("%-{$klen}s  %s\n", $k.':', $v);
         }
     }
     // }}}

ext/session/tests/save_handler.inc

@@ -27,7 +27,7 @@ function open($save_path, $session_name) {
     global $session_save_path, $name;
     $session_save_path = $save_path;
     $name = $session_name;
-    echo "Open [${session_save_path},${session_name}]\n";
+    echo "Open [{$session_save_path},{$session_name}]\n";
 
     // MUST return bool. Return TRUE for success.
     return true;
@@ -39,7 +39,7 @@ function close() {
     // NOTE: This function should unlock session data, if write() does not unlock it.
 
     global $session_save_path, $name;
-    echo "Close [${session_save_path},${name}]\n";
+    echo "Close [{$session_save_path},{$name}]\n";
 
     // MUST return bool. Return TRUE for success.
     return true;
@@ -54,7 +54,7 @@ function read($id) {
 
     global $session_save_path, $name, $session_id;
     $session_id = $id;
-    echo "Read [${session_save_path},${id}]\n";
+    echo "Read [{$session_save_path},{$id}]\n";
     $session_file = "$session_save_path/".SESSION_FILE_PREFIX.$id;
     // read MUST create file. Otherwise, strict mode will not work
     touch($session_file);
@@ -74,7 +74,7 @@ function write($id, $session_data) {
 
     global $session_save_path, $name, $session_id;
     $session_id = $id;
-    echo "Write [${session_save_path},${id},${session_data}]\n";
+    echo "Write [{$session_save_path},{$id},{$session_data}]\n";
     $session_file = "$session_save_path/".SESSION_FILE_PREFIX.$id;
     if ($fp = fopen($session_file, "w")) {
         $return = fwrite($fp, $session_data);
@@ -91,7 +91,7 @@ function destroy($id) {
     // string $id - Session ID string
 
     global $session_save_path, $name;
-    echo "Destroy [${session_save_path},${id}]\n";
+    echo "Destroy [{$session_save_path},{$id}]\n";
     $session_file = "$session_save_path/".SESSION_FILE_PREFIX.$id;
     unlink($session_file);
 
@@ -136,7 +136,7 @@ function create_sid() {
     //       e.g. hash('sha2', random_bytes(64)) or use /dev/urandom
 
     $id = ('PHPT-'.time());
-    echo "CreateID [${id}]\n";
+    echo "CreateID [{$id}]\n";
 
     // MUST return session ID string.
     // Return FALSE for error.
@@ -148,7 +148,7 @@ function validate_sid($id) {
     // string $id - Session ID string
 
     global $session_save_path, $name;
-    echo "ValidateID [${session_save_path},${id}]\n";
+    echo "ValidateID [{$session_save_path},{$id}]\n";
     $session_file = "$session_save_path/".SESSION_FILE_PREFIX.$id;
     $ret = file_exists($session_file);
 
@@ -168,7 +168,7 @@ function update($id, $session_data) {
     //       support time stamp updating, you must not define this.
 
     global $session_save_path, $name;
-    echo "Update [${session_save_path},${id}]\n";
+    echo "Update [{$session_save_path},{$id}]\n";
     $session_file = "$session_save_path/".SESSION_FILE_PREFIX.$id;
     $ret = touch($session_file);
 

ext/soap/tests/bug73037.phpt

@@ -88,7 +88,7 @@ Content-Type: application/soap+xml; charset=UTF-8
 Accept: application/soap+xml, application/dime, multipart/related, text/*
 SOAPAction: "urn:adressen#adressen#SetAda"
 Expect: 100-continue
-Content-Length: ${len}
+Content-Length: {$len}
 HDRS;
         if ($b) {
             $hdrs .="\nContent-Encoding: gzip";

ext/standard/tests/file/windows_mb_path/test_big5_1.phpt

@@ -25,9 +25,9 @@ include __DIR__ . DIRECTORY_SEPARATOR . "util.inc";
 
 $item = "���զh�r�`���|"; // BIG5 string
 $prefix = create_data("dir_big5", $item . "5", 950);
-$path = $prefix . DIRECTORY_SEPARATOR . "${item}5";
+$path = $prefix . DIRECTORY_SEPARATOR . "{$item}5";
 
-$subpath = $path . DIRECTORY_SEPARATOR . "${item}4";
+$subpath = $path . DIRECTORY_SEPARATOR . "{$item}4";
 
 /* The mb dirname exists*/
 var_dump(file_exists($path));