test: add unit tests for ddless_eval_in_context() functionality

Author: jeffleyd

tests/EvalInContextTest.php

@@ -0,0 +1,165 @@
+<?php
+/**
+ * Tests for ddless_eval_in_context()
+ * Run: php tests/php/EvalInContextTest.php
+ */
+require_once __DIR__ . '/bootstrap.php';
+
+// ── Helper class for $this binding tests ────────────────────────────────────
+
+class EvalTestDummy {
+    public string $name = 'Alice';
+    private int $secret = 42;
+
+    public function getSecret(): int {
+        return $this->secret;
+    }
+}
+
+section('ddless_eval_in_context() — returnValue=true (default)');
+
+test('evaluates simple expression', function () {
+    $result = ddless_eval_in_context('1 + 2', [], []);
+    assert_eq(3, $result);
+});
+
+test('evaluates string expression', function () {
+    $result = ddless_eval_in_context('"hello " . "world"', [], []);
+    assert_eq('hello world', $result);
+});
+
+test('accesses scope variables', function () {
+    $vars = ['x' => 10, 'y' => 20];
+    $result = ddless_eval_in_context('$x + $y', $vars, []);
+    assert_eq(30, $result);
+});
+
+test('accesses array scope variable', function () {
+    $vars = ['items' => ['a', 'b', 'c']];
+    $result = ddless_eval_in_context('count($items)', $vars, []);
+    assert_eq(3, $result);
+});
+
+test('scope variables do not leak between calls', function () {
+    ddless_eval_in_context('$leak = 999', ['leak' => 999], []);
+    // $leak should not exist in the next call
+    $result = ddless_eval_in_context('isset($leak) ? $leak : null', [], []);
+    assert_null($result);
+});
+
+section('ddless_eval_in_context() — returnValue=false (playground mode)');
+
+test('executes raw code and returns result', function () {
+    $result = ddless_eval_in_context('$a = 5; $b = 10; return $a * $b;', [], [], false);
+    assert_eq(50, $result);
+});
+
+test('multi-line code with return', function () {
+    $code = <<<'PHP'
+$items = [1, 2, 3, 4, 5];
+$sum = 0;
+foreach ($items as $i) {
+    $sum += $i;
+}
+return $sum;
+PHP;
+    $result = ddless_eval_in_context($code, [], [], false);
+    assert_eq(15, $result);
+});
+
+test('returns null when no return statement', function () {
+    $result = ddless_eval_in_context('$x = 42;', [], [], false);
+    assert_null($result);
+});
+
+test('accesses scope variables in raw mode', function () {
+    $vars = ['user' => ['name' => 'Bob', 'age' => 30]];
+    $result = ddless_eval_in_context('return $user["name"] . " is " . $user["age"];', $vars, [], false);
+    assert_eq('Bob is 30', $result);
+});
+
+test('can use built-in functions', function () {
+    $result = ddless_eval_in_context('return array_map(fn($v) => $v * 2, [1,2,3]);', [], [], false);
+    assert_eq([2, 4, 6], $result);
+});
+
+test('can use anonymous functions', function () {
+    $code = <<<'PHP'
+$fn = function($a, $b) { return $a + $b; };
+return $fn(3, 7);
+PHP;
+    $result = ddless_eval_in_context($code, [], [], false);
+    assert_eq(10, $result);
+});
+
+section('ddless_eval_in_context() — $this binding');
+
+test('binds $this when backtrace has object', function () {
+    $obj = new EvalTestDummy();
+    $backtrace = [
+        ['function' => 'someMethod', 'object' => $obj],
+    ];
+    $result = ddless_eval_in_context('$this->name', [], $backtrace);
+    assert_eq('Alice', $result);
+});
+
+test('$this can access private members via closure binding', function () {
+    $obj = new EvalTestDummy();
+    $backtrace = [
+        ['function' => 'someMethod', 'object' => $obj],
+    ];
+    $result = ddless_eval_in_context('$this->getSecret()', [], $backtrace);
+    assert_eq(42, $result);
+});
+
+test('skips ddless_ frames in backtrace', function () {
+    $obj = new EvalTestDummy();
+    $backtrace = [
+        ['function' => 'ddless_step_check'],
+        ['function' => 'ddless_handle_breakpoint'],
+        ['function' => 'someMethod', 'object' => $obj],
+    ];
+    $result = ddless_eval_in_context('$this->name', [], $backtrace);
+    assert_eq('Alice', $result);
+});
+
+test('no $this when backtrace has no object', function () {
+    $backtrace = [
+        ['function' => 'plainFunction'],
+    ];
+    // Without object binding, $this is not available — eval returns null via @
+    $result = ddless_eval_in_context('isset($this) ? "has this" : "no this"', [], $backtrace);
+    assert_eq('no this', $result);
+});
+
+test('combines scope variables with $this binding', function () {
+    $obj = new EvalTestDummy();
+    $backtrace = [
+        ['function' => 'someMethod', 'object' => $obj],
+    ];
+    $vars = ['suffix' => '!'];
+    $result = ddless_eval_in_context('$this->name . $suffix', $vars, $backtrace);
+    assert_eq('Alice!', $result);
+});
+
+section('ddless_eval_in_context() — error handling');
+
+test('syntax error throws ParseError', function () {
+    $threw = false;
+    try {
+        ddless_eval_in_context('invalid syntax !!!', [], []);
+    } catch (\ParseError $e) {
+        $threw = true;
+    }
+    assert_true($threw, 'eval with syntax error should throw ParseError');
+});
+
+test('undefined variable returns null (suppressed by @)', function () {
+    $result = ddless_eval_in_context('$nonExistentVar', [], []);
+    assert_null($result);
+});
+
+// Print results if run standalone
+if (basename($argv[0] ?? '') === basename(__FILE__)) {
+    exit(print_test_results());
+}

tests/run-all.php

@@ -18,6 +18,7 @@
     'NormalizeValueTest.php',
     'InstrumentTraceTest.php',
     'HttpRequestTest.php',
+    'EvalInContextTest.php',
 ];
 
 foreach ($testFiles as $file) {