Introduce Stmt\Block

Stmt\Block will be created for { $a; } style blocks, unless these
occur directly inside some structure that is usually combined
with a block.

For example if ($a) { $b; } will continue to use the old
representation (plain array in in If_::$stmts), but a free-standing
{ $b; } will become a Stmt\Block.

Fixes #590.

grammar/php.y

@@ -366,21 +366,13 @@ inner_statement:
 ;
 
 non_empty_statement:
-      '{' inner_statement_list '}'
+      '{' inner_statement_list '}'                          { $$ = Stmt\Block[$2]; }
-    {
+    | T_IF '(' expr ')' blocklike_statement elseif_list else_single
-        if ($2) {
+          { $$ = Stmt\If_[$3, ['stmts' => $5, 'elseifs' => $6, 'else' => $7]]; }
-            $$ = $2; prependLeadingComments($$);
-        } else {
-            makeNop($$);
-            if (null === $$) { $$ = array(); }
-        }
-    }
-    | T_IF '(' expr ')' statement elseif_list else_single
-          { $$ = Stmt\If_[$3, ['stmts' => toArray($5), 'elseifs' => $6, 'else' => $7]]; }
     | T_IF '(' expr ')' ':' inner_statement_list new_elseif_list new_else_single T_ENDIF ';'
           { $$ = Stmt\If_[$3, ['stmts' => $6, 'elseifs' => $7, 'else' => $8]]; }
     | T_WHILE '(' expr ')' while_statement                  { $$ = Stmt\While_[$3, $5]; }
-    | T_DO statement T_WHILE '(' expr ')' ';'               { $$ = Stmt\Do_   [$5, toArray($2)]; }
+    | T_DO blocklike_statement T_WHILE '(' expr ')' ';'     { $$ = Stmt\Do_   [$5, $2]; }
     | T_FOR '(' for_expr ';'  for_expr ';' for_expr ')' for_statement
           { $$ = Stmt\For_[['init' => $3, 'cond' => $5, 'loop' => $7, 'stmts' => $9]]; }
     | T_SWITCH '(' expr ')' switch_case_list                { $$ = Stmt\Switch_[$3, $5]; }
@@ -416,14 +408,16 @@ non_empty_statement:
           { $$ = Stmt\TryCatch[$3, $5, $6]; $this->checkTryCatch($$); }
     | T_GOTO identifier_not_reserved semi                   { $$ = Stmt\Goto_[$2]; }
     | identifier_not_reserved ':'                           { $$ = Stmt\Label[$1]; }
-    | error                                                 { $$ = array(); /* means: no statement */ }
+    | error                                                 { $$ = null; /* means: no statement */ }
 ;
 
 statement:
       non_empty_statement
-    | ';'
+    | ';'                                                   { makeNop($$); }
-          { makeNop($$);
+;
-            if ($$ === null) $$ = array(); /* means: no statement */ }
+
+blocklike_statement:
+     statement                                              { toBlock($1); }
 ;
 
 catches:
@@ -554,17 +548,17 @@ non_empty_class_name_list:
 ;
 
 for_statement:
-      statement                                             { $$ = toArray($1); }
+      blocklike_statement
     | ':' inner_statement_list T_ENDFOR ';'                 { $$ = $2; }
 ;
 
 foreach_statement:
-      statement                                             { $$ = toArray($1); }
+      blocklike_statement
     | ':' inner_statement_list T_ENDFOREACH ';'             { $$ = $2; }
 ;
 
 declare_statement:
-      non_empty_statement                                   { $$ = toArray($1); }
+      non_empty_statement                                   { toBlock($1); }
     | ';'                                                   { $$ = null; }
     | ':' inner_statement_list T_ENDDECLARE ';'             { $$ = $2; }
 ;
@@ -624,7 +618,7 @@ match_arm:
 ;
 
 while_statement:
-      statement                                             { $$ = toArray($1); }
+      blocklike_statement                                   { $$ = $1; }
     | ':' inner_statement_list T_ENDWHILE ';'               { $$ = $2; }
 ;
 
@@ -634,7 +628,7 @@ elseif_list:
 ;
 
 elseif:
-      T_ELSEIF '(' expr ')' statement                       { $$ = Stmt\ElseIf_[$3, toArray($5)]; }
+      T_ELSEIF '(' expr ')' blocklike_statement             { $$ = Stmt\ElseIf_[$3, $5]; }
 ;
 
 new_elseif_list:
@@ -649,7 +643,7 @@ new_elseif:
 
 else_single:
       /* empty */                                           { $$ = null; }
-    | T_ELSE statement                                      { $$ = Stmt\Else_[toArray($2)]; }
+    | T_ELSE blocklike_statement                            { $$ = Stmt\Else_[$2]; }
 ;
 
 new_else_single:

grammar/phpyLang.php

@@ -87,14 +87,15 @@ function resolveMacros($code) {
             if ('pushNormalizing' === $name) {
                 assertArgs(2, $args, $name);
 
-                return 'if (is_array(' . $args[1] . ')) { $$ = array_merge(' . $args[0] . ', ' . $args[1] . '); }'
+                return 'if (' . $args[1] . ' !== null) { ' . $args[0] . '[] = ' . $args[1] . '; } $$ = ' . $args[0] . ';';
-                       . ' else { ' . $args[0] . '[] = ' . $args[1] . '; $$ = ' . $args[0] . '; }';
             }
 
-            if ('toArray' == $name) {
+            if ('toBlock' == $name) {
                 assertArgs(1, $args, $name);
 
-                return 'is_array(' . $args[0] . ') ? ' . $args[0] . ' : array(' . $args[0] . ')';
+                return 'if (' . $args[0] . ' instanceof Stmt\Block) { $$ = ' . $args[0] . '->stmts; } '
+                     . 'else if (' . $args[0] . ' === null) { $$ = []; } '
+                     . 'else { $$ = [' . $args[0] . ']; }';
             }
 
             if ('parseVar' === $name) {
@@ -122,15 +123,6 @@ function resolveMacros($code) {
                 return $args[0] . ' = $this->maybeCreateZeroLengthNop($this->tokenPos);';
             }
 
-            if ('prependLeadingComments' === $name) {
-                assertArgs(1, $args, $name);
-
-                return '$comments = $this->getCommentsBeforeToken($this->tokenStartStack[#1]); $stmts = ' . $args[0] . '; '
-                       . 'if (!empty($comments)) {'
-                       . '$stmts[0]->setAttribute(\'comments\', '
-                       . 'array_merge($comments, $stmts[0]->getAttribute(\'comments\', []))); }';
-            }
-
             return $matches[0];
         },
         $code

lib/PhpParser/Internal/TokenStream.php

@@ -195,12 +195,6 @@ class TokenStream {
         return false;
     }
 
-    public function haveBracesInRange(int $startPos, int $endPos): bool {
-        return $this->haveTokenInRange($startPos, $endPos, '{')
-            || $this->haveTokenInRange($startPos, $endPos, T_CURLY_OPEN)
-            || $this->haveTokenInRange($startPos, $endPos, '}');
-    }
-
     public function haveTagInRange(int $startPos, int $endPos): bool {
         return $this->haveTokenInRange($startPos, $endPos, \T_OPEN_TAG)
             || $this->haveTokenInRange($startPos, $endPos, \T_CLOSE_TAG);

lib/PhpParser/Node/Stmt/Block.php

@@ -0,0 +1,29 @@
+<?php declare(strict_types=1);
+
+namespace PhpParser\Node\Stmt;
+
+use PhpParser\Node\Stmt;
+
+class Block extends Stmt {
+    /** @var Stmt[] Statements */
+    public array $stmts;
+
+    /**
+     * A block of statements.
+     *
+     * @param Stmt[] $stmts Statements
+     * @param array<string, mixed> $attributes Additional attributes
+     */
+    public function __construct(array $stmts, array $attributes = []) {
+        $this->attributes = $attributes;
+        $this->stmts = $stmts;
+    }
+
+    public function getType(): string {
+        return 'Stmt_Block';
+    }
+
+    public function getSubNodeNames(): array {
+        return ['stmts'];
+    }
+}

lib/PhpParser/PrettyPrinter/Standard.php

@@ -1012,6 +1012,10 @@ class Standard extends PrettyPrinterAbstract {
         return '';
     }
 
+    protected function pStmt_Block(Stmt\Block $node): string {
+        return '{' . $this->pStmts($node->stmts) . $this->nl . '}';
+    }
+
     // Helpers
 
     protected function pClassCommon(Stmt\Class_ $node, string $afterClassToken): string {

lib/PhpParser/PrettyPrinterAbstract.php

@@ -826,9 +826,8 @@ abstract class PrettyPrinterAbstract implements PrettyPrinter {
                 }
 
                 if ($skipRemovedNode) {
-                    if ($isStmtList && ($this->origTokens->haveBracesInRange($pos, $itemStartPos) ||
+                    if ($isStmtList && $this->origTokens->haveTagInRange($pos, $itemStartPos)) {
-                                        $this->origTokens->haveTagInRange($pos, $itemStartPos))) {
+                        // We'd remove an opening/closing PHP tag.
-                        // We'd remove the brace of a code block.
                         // TODO: Preserve formatting.
                         $this->setIndentLevel($origIndentLevel);
                         return null;
@@ -937,9 +936,8 @@ abstract class PrettyPrinterAbstract implements PrettyPrinter {
                         $pos, $itemStartPos, $indentAdjustment);
                     $skipRemovedNode = true;
                 } else {
-                    if ($isStmtList && ($this->origTokens->haveBracesInRange($pos, $itemStartPos) ||
+                    if ($isStmtList && $this->origTokens->haveTagInRange($pos, $itemStartPos)) {
-                                        $this->origTokens->haveTagInRange($pos, $itemStartPos))) {
+                        // We'd remove an opening/closing PHP tag.
-                        // We'd remove the brace of a code block.
                         // TODO: Preserve formatting.
                         return null;
                     }
@@ -1540,6 +1538,7 @@ abstract class PrettyPrinterAbstract implements PrettyPrinter {
             Stmt\Function_::class . '->stmts' => "\n",
             Stmt\If_::class . '->stmts' => "\n",
             Stmt\Namespace_::class . '->stmts' => "\n",
+            Stmt\Block::class . '->stmts' => "\n",
 
             // Attribute groups
             Stmt\Class_::class . '->attrGroups' => "\n",

test/code/formatPreservation/basic.test

@@ -153,8 +153,9 @@ $stmts[1] = $tmp;
  * fallback. */
 -----
 <?php
-
+{
-$x;
+    $x;
+}
 function foo() {
     foo();
     /*
@@ -186,4 +187,4 @@ echo "{$bar}bar";
 [$a
 ,$b
 ,
-,] = $b;
+,] = $b;

test/code/formatPreservation/listInsertion.test

@@ -354,3 +354,16 @@ array_splice($stmts[0]->expr->var->items, 1, 0, [null]);
 -----
 <?php
 list($x, , $y) = $z;
+-----
+<?php
+{
+    $a; $b;
+}
+-----
+$stmts[0]->stmts[] = new Stmt\Expression(new Expr\Variable('c'));
+-----
+<?php
+{
+    $a; $b;
+    $c;
+}

test/code/formatPreservation/listRemoval.test

@@ -70,7 +70,6 @@ $y;
 array_splice($stmts, 0, 1, []);
 -----
 <?php
-
 $y;
 -----
 <?php
@@ -80,8 +79,7 @@ $x;
 array_splice($stmts, 0, 1, []);
 -----
 <?php
-
+{ $y; }
-$y;
 -----
 <?php
 $x;
@@ -90,7 +88,6 @@ $x;
 array_pop($stmts);
 -----
 <?php
-
 $x;
 -----
 <?php
@@ -100,8 +97,7 @@ $y;
 array_pop($stmts);
 -----
 <?php
-
+{ $x; }
-$x;
 -----
 <?php
 // Foo

test/code/parser/blockComments.test

@@ -15,20 +15,34 @@ Comments on blocks
 {}
 -----
 array(
-    0: Stmt_Expression(
+    0: Stmt_Block(
-        expr: Expr_Variable(
+        stmts: array(
-            name: a
+            0: Stmt_Block(
-            comments: array(
+                stmts: array(
-                0: // baz
+                    0: Stmt_Expression(
+                        expr: Expr_Variable(
+                            name: a
+                            comments: array(
+                                0: // baz
+                            )
+                        )
+                        comments: array(
+                            0: // baz
+                        )
+                    )
+                )
+                comments: array(
+                    0: // bar
+                )
             )
         )
         comments: array(
             0: // foo
-            1: // bar
-            2: // baz
         )
     )
-    1: Stmt_Nop(
+    1: Stmt_Block(
+        stmts: array(
+        )
         comments: array(
             0: // empty
         )

test/code/parser/errorHandling/recovery.test

@@ -223,13 +223,17 @@ array(
             )
         )
     )
-    1: Stmt_Expression(
+    1: Stmt_Block(
-        expr: Expr_Assign(
+        stmts: array(
-            var: Expr_Variable(
+            0: Stmt_Expression(
-                name: j
+                expr: Expr_Assign(
-            )
+                    var: Expr_Variable(
-            expr: Scalar_Int(
+                        name: j
-                value: 1
+                    )
+                    expr: Scalar_Int(
+                        value: 1
+                    )
+                )
             )
         )
     )

test/code/parser/nopPositions.test

@@ -19,9 +19,13 @@ array(
 -----
 !!positions
 array(
-    0: Stmt_Nop[3:0 - 3:17](
+    0: Stmt_Block[2:1 - 4:1](
-        comments: array(
+        stmts: array(
-            0: /* comment */
+            0: Stmt_Nop[3:0 - 3:17](
+                comments: array(
+                    0: /* comment */
+                )
+            )
         )
     )
 )

test/code/parser/stmt/class/name.test

@@ -42,6 +42,10 @@ array(
 -----
 Syntax error, unexpected T_STATIC, expecting T_STRING from 1:13 to 1:18
 array(
+    0: Stmt_Block(
+        stmts: array(
+        )
+    )
 )
 -----
 <?php class A extends self {}
@@ -211,6 +215,10 @@ array(
 -----
 Syntax error, unexpected T_STATIC, expecting T_STRING from 1:17 to 1:22
 array(
+    0: Stmt_Block(
+        stmts: array(
+        )
+    )
 )
 -----
 <?php interface A extends self {}

test/code/parser/stmt/class/readonlyAsClassName.test

@@ -5,6 +5,10 @@ class ReadOnly {}
 -----
 Syntax error, unexpected T_READONLY, expecting T_STRING from 2:7 to 2:14
 array(
+    0: Stmt_Block(
+        stmts: array(
+        )
+    )
 )
 -----
 <?php

test/code/parser/stmt/declare.test

@@ -4,7 +4,9 @@ Declare
 
 declare (X='Y');
 
-declare (A='B', C='D') {}
+declare (A='B', C='D') {
+    echo "foo";
+}
 
 declare (A='B', C='D'):
 enddeclare;
@@ -43,6 +45,13 @@ array(
             )
         )
         stmts: array(
+            0: Stmt_Echo(
+                exprs: array(
+                    0: Scalar_String(
+                        value: foo
+                    )
+                )
+            )
         )
     )
     2: Stmt_Declare(

test/code/parser/stmt/namespace/groupUseErrors.test

@@ -63,17 +63,21 @@ array(
             0: // Missing NS separator
         )
     )
-    1: Stmt_Expression(
+    1: Stmt_Block(
-        expr: Expr_ConstFetch(
+        stmts: array(
-            name: Name(
+            0: Stmt_Expression(
-                name: Bar
+                expr: Expr_ConstFetch(
+                    name: Name(
+                        name: Bar
+                    )
+                )
             )
-        )
+            1: Stmt_Expression(
-    )
+                expr: Expr_ConstFetch(
-    2: Stmt_Expression(
+                    name: Name(
-        expr: Expr_ConstFetch(
+                        name: Baz
-            name: Name(
+                    )
-                name: Baz
+                )
             )
         )
     )

test/code/prettyPrinter/stmt/block.test

@@ -0,0 +1,28 @@
+Block statements
+-----
+<?php
+echo "a";
+{
+}
+{
+    echo "b";
+}
+if ($c) {
+    echo "c";
+    {
+        echo "d";
+    }
+}
+-----
+echo "a";
+{
+}
+{
+    echo "b";
+}
+if ($c) {
+    echo "c";
+    {
+        echo "d";
+    }
+}