fix(parser): parse do-while body before condition

phpunit/code/control-flow/while-body-defined-condition.php

@@ -0,0 +1,8 @@
+<?php
+
+function while_body_defined_condition(): void
+{
+    while (count($results) > 0) {
+        $results = [1, 2, 3];
+    }
+}

phpunit/src/LoopControlTest.php

@@ -22,4 +22,12 @@ class LoopControlTest extends \BaseTest
     {
         $this->compile('control-flow/loop-switch-continue.php');
     }
+
+    public function testWhileConditionIsStillParsedBeforeItsBody(): void
+    {
+        $this->exec(
+            'Undefined variable `$results`',
+            'control-flow/while-body-defined-condition.php',
+        );
+    }
 }

src/Parser/LoopControlTrait.php

@@ -148,6 +148,10 @@ trait LoopControlTrait
     protected function parseDo(Node\Stmt\Do_ $v): string
     {
         $stmts = $v->stmts;
+        // A do-while body always runs before its condition. Parse it first so
+        // variables introduced by the body are available while lowering the
+        // condition, matching PHP's execution order.
+        $bodyCode = $this->parseBlockStmts($stmts);
         $this->assertExprCanBeUsedAsCondition($v->cond, 'do-while condition');
         [$cond, $beforeStmts, $afterStmts] = $this->parseExprWithCapturedStmts($v->cond);
         if ($beforeStmts || $afterStmts) {
@@ -167,7 +171,7 @@ trait LoopControlTrait
         }
         $code  = $this->parseBeforeStmtLines() . PHP_EOL;
         $code .= 'do {' . PHP_EOL;
-        $code .= $this->parseBlockStmts($stmts);
+        $code .= $bodyCode;
         $code .= $this->genLoopEndFlagCheck();
         $code .= $this->getIndent() . '} while (' . $cond . ');' . PHP_EOL;
 

tests/compiler/control_flow/do-while-body-defined-condition.phpt

@@ -0,0 +1,21 @@
+--TEST--
+do-while condition can use a variable first defined in the loop body
+--FILE--
+<?php
+
+function main(): void
+{
+    $page = 1;
+    do {
+        $results = [1, 2, 3];
+        echo "page=$page count=", count($results), "\n";
+        $page++;
+    } while (count($results) === 3 && $page <= 2);
+
+    echo "Done\n";
+}
+?>
+--EXPECT--
+page=1 count=3
+page=2 count=3
+Done