Fix echo 0; (or 0.0, or "0") not triggering the development console

ChangeLog.md

@@ -3,6 +3,8 @@ Web change log
 
 ## ?.?.? / ????-??-??
 
+* Fixed `echo 0;` (or 0.0, or "0") not triggering the development console
+  (@thekid)
 * Fixed trace data not appearing in logfile in development mode - @thekid
 * Merged PR #115: Add `web.Headers::qfactors()`, which can be used when
   implementing content negotiation

src/main/php/xp/web/dev/Console.class.php

@@ -8,7 +8,8 @@
  * inside an easily readable format above the real output, using a 200
  * HTTP response status.
  *
- * @see   php://ob_start
+ * @see   https://www.php.net/ob_start
+ * @test  web.unittest.server.ConsoleTest
  */
 class Console implements Filter {
   private $template;
@@ -56,7 +57,7 @@ public function filter($req, $res, $invocation) {
 
     $res->trace= $buffer->trace;
     $out= $buffer->output();
-    if (empty($debug)) {
+    if (0 === strlen($debug)) {
       $out->drain($res);
     } else {
       $res->status(200, 'Debug');

src/test/php/web/unittest/server/ConsoleTest.class.php

@@ -0,0 +1,134 @@
+<?php namespace web\unittest\server;
+
+use test\{Assert, Test, Values};
+use web\io\{TestInput, TestOutput};
+use web\{Filters, Request, Response};
+use xp\web\dev\Console;
+
+class ConsoleTest {
+
+  /**
+   * Handles a request with the given headers and handler function,
+   * returning the response.
+   *
+   * @param  function(web.Request, web.Response): var $handler
+   * @return web.Response
+   */
+  private function handle($handler) {
+    $compress= new Filters([new Console()], $handler);
+    $req= new Request(new TestInput('GET', '/?test=true'));
+    $res= new Response(new TestOutput());
+
+    foreach ($compress->handle($req, $res) ?? [] as $_) { }
+    return $res;
+  }
+
+  #[Test]
+  public function can_create() {
+    new Console();
+  }
+
+  #[Test]
+  public function send() {
+    $res= $this->handle(function($req, $res) {
+      $res->send('Test', 'text/plain; charset=utf-8');
+    });
+
+    Assert::equals(
+      "HTTP/1.1 200 OK\r\n".
+      "Content-Type: text/plain; charset=utf-8\r\n".
+      "Content-Length: 4\r\n".
+      "\r\n".
+      "Test",
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test]
+  public function stream() {
+    $res= $this->handle(function($req, $res) {
+      $res->header('Content-Type', 'text/plain; charset=utf-8');
+      $stream= $res->stream();
+      $stream->write('Test');
+      $stream->close();
+    });
+
+    Assert::equals(
+      "HTTP/1.1 200 OK\r\n".
+      "Content-Type: text/plain; charset=utf-8\r\n".
+      "Transfer-Encoding: chunked\r\n".
+      "\r\n".
+      "4\r\nTest\r\n0\r\n\r\n",
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test]
+  public function empty_echo_does_not_trigger() {
+    $res= $this->handle(function($req, $res) {
+      echo '';
+      $res->send('Test', 'text/plain; charset=utf-8');
+    });
+
+    Assert::equals(
+      "HTTP/1.1 200 OK\r\n".
+      "Content-Type: text/plain; charset=utf-8\r\n".
+      "Content-Length: 4\r\n".
+      "\r\n".
+      "Test",
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test, Values(['true', '0', 0, 0.0])]
+  public function echo_output_appears_in_console($arg) {
+    $res= $this->handle(function($req, $res) use($arg) {
+      echo $arg;
+      $res->send('Test', 'text/plain; charset=utf-8');
+    });
+
+    Assert::matches(
+      '/<pre id="output">'.(string)$arg.'<\/pre>/',
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test]
+  public function var_dump_output_appears_in_console() {
+    $res= $this->handle(function($req, $res) {
+      var_dump($req->param('test'));
+      $res->send('Test', 'text/plain; charset=utf-8');
+    });
+
+    Assert::matches(
+      '/<pre id="output">string\(4\) &quot;true&quot;\n<\/pre>/',
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test]
+  public function status_appears_in_console() {
+    $res= $this->handle(function($req, $res) {
+      echo 'Test';
+      $res->answer(204);
+    });
+
+    Assert::matches(
+      '/HTTP\/1.1 <span id="status">204 No Content<\/span>/',
+      $res->output()->bytes()
+    );
+  }
+
+  #[Test]
+  public function headers_appear_in_console() {
+    $res= $this->handle(function($req, $res) {
+      echo $req->param('test');
+      $res->send('Test', 'text/plain; charset=utf-8');
+    });
+
+    Assert::matches(
+      '/<td class="name">Content-Type<\/td>.*<td class="value">text\/plain; charset=utf-8<\/td>/s',
+      $res->output()->bytes()
+    );
+  }
+}