fix: Check that the result of pcntl_waitpid is the PID of a managed process

.github/CONTRIBUTING.md

@@ -18,7 +18,8 @@ Thank you for your interest in contributing to PHP_CodeSniffer!
     * [Finding Something to Work on](#finding-something-to-work-on)
     * [Getting Started](#getting-started)
     * [While Working on a Patch](#while-working-on-a-patch)
-    * [Writing Tests](#writing-tests)
+    * [Writing Unit/Integration Tests](#writing-unitintegration-tests)
+    * [Writing End-to-End Tests](#writing-end-to-end-tests)
     * [Submitting Your Pull Request](#submitting-your-pull-request)
 * [Licensing](#licensing)
 
@@ -268,7 +269,7 @@ To help you with this, a number of convenience scripts are available:
 N.B.: You can ignore any skipped tests as these are for external tools.
 
 
-### Writing Tests
+### Writing Unit/Integration Tests
 
 Tests for the PHP_CodeSniffer engine can be found in the `tests/Core` directory.
 Tests for individual sniffs can be found in the `src/Standards/[StandardName]/Tests/[Category]/` directory.
@@ -376,7 +377,7 @@ To run the tests specific to the use of `PHP_CODESNIFFER_CBF === true`:
     vendor/bin/phpunit --group CBF --exclude-group nothing
     ```
 
-#### Other notes about writing tests
+#### Other notes about writing unit/integration tests
 
 * The `Config` class uses a number of static properties and can have a performance impact on the tests too.
     To get round both these issues, use the `ConfigDouble` class instead.
@@ -387,6 +388,24 @@ To run the tests specific to the use of `PHP_CODESNIFFER_CBF === true`:
 * When using data providers, define them immediately below the corresponding test method.
 * When a test method has only one data provider, it is considered best practice to closely couple the test and data provider methods via their names. I.e. the data provider's name should match the test method name, replacing the "test" prefix with "data". For example, the data provider for a method named `testSomething()` should be `dataSomething()`.
 
+
+### Writing End-to-End Tests
+
+Bash-based end-to-end tests can be written using the [Bashunit](https://bashunit.typeddevs.com/) test tooling.
+
+To install bashunit, follow the [installation guide](https://bashunit.typeddevs.com/installation).
+
+You can then run the bashunit tests on Linux/Mac/WSL, like so:
+```bash
+./lib/bashunit -p tests/EndToEnd
+```
+
+> Note: these tests will not run in the Windows native CMD shell. When on Windows, either use WSL or use the "git bash" shell.
+
+When writing end-to-end tests, please use fixtures for the "files under scan" to make the tests stable.
+These fixtures can be placed in the `tests/EndToEnd/Fixtures` subdirectory.
+
+
 ### Submitting Your Pull Request
 
 Some guidelines for submitting pull requests (PRs) and improving the chance that your PR will be merged:

.github/workflows/end-to-end-tests.yml

@@ -0,0 +1,60 @@
+name: E2E Tests
+
+on:
+  # Run on pushes to `master`/`4.0` and on all pull requests.
+  # Prevent the build from running when there are only irrelevant changes.
+  push:
+    branches:
+      - master
+      - 4.0
+    tags:
+      - '**'
+    paths-ignore:
+      - '**.md'
+  pull_request:
+  # Allow manually triggering the workflow.
+  workflow_dispatch:
+
+jobs:
+  bash-tests:
+    # Cancels all previous runs of this particular job for the same branch that have not yet completed.
+    concurrency:
+      # The concurrency group contains the workflow name, job name, job index and the branch name.
+      group: ${{ github.workflow }}-${{ github.job }}-${{ strategy.job-index }}-${{ github.ref }}
+      cancel-in-progress: true
+
+    runs-on: 'ubuntu-latest'
+
+    strategy:
+      matrix:
+        php: ['5.4', '5.5', '5.6', '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3', '8.4', '8.5']
+
+    # yamllint disable-line rule:line-length
+    name: "E2E PHP: ${{ matrix.php }}"
+
+    continue-on-error: ${{ matrix.php == '8.5' }}
+
+    steps:
+      - name: Prepare git to leave line endings alone
+        run: git config --global core.autocrlf input
+
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          ini-values: "error_reporting=-1, display_errors=On"
+          coverage: none
+
+      - name: "Install bashunit"
+        shell: bash
+        run: |
+          curl -s https://bashunit.typeddevs.com/install.sh > install.sh
+          chmod +x install.sh
+          ./install.sh
+
+      - name: "Run bashunit tests"
+        shell: bash
+        run: "./lib/bashunit -p tests/EndToEnd"

.gitignore

@@ -8,3 +8,5 @@
 composer.lock
 phpstan.neon
 /node_modules/
+/tests/EndToEnd/Fixtures/*.fixed
+/lib/

phpcs.xml.dist

@@ -11,6 +11,7 @@
     <exclude-pattern>*/src/Standards/*/Tests/*\.(inc|css|js)$</exclude-pattern>
     <exclude-pattern>*/tests/Core/*/*\.(inc|css|js)$</exclude-pattern>
     <exclude-pattern>*/tests/Core/*/Fixtures/*\.php$</exclude-pattern>
+    <exclude-pattern>*/tests/EndToEnd/Fixtures/*\.inc$</exclude-pattern>
 
     <arg name="basepath" value="."/>
     <arg name="colors"/>

src/Runner.php

@@ -764,7 +764,7 @@ public function processFile($file)
      * The reporting information returned by each child process is merged
      * into the main reporter class.
      *
-     * @param array $childProcs An array of child processes to wait for.
+     * @param array<int, string> $childProcs An array of child processes to wait for.
      *
      * @return bool
      */
@@ -777,7 +777,8 @@ private function processChildProcs($childProcs)
 
         while (count($childProcs) > 0) {
             $pid = pcntl_waitpid(0, $status);
-            if ($pid <= 0) {
+            if ($pid <= 0 || isset($childProcs[$pid]) === false) {
+                // No child or a child with an unmanaged PID was returned.
                 continue;
             }
 

tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc

@@ -0,0 +1,18 @@
+<?php
+
+/**
+ * Class containing no style errors according to the end-to-end tests phpcs.xml.dist.
+ *
+ * @copyright 2025 PHPCSStandards and contributors
+ * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ */
+
+namespace PHP_CodeSniffer\Tests\EndToEnd\Fixtures;
+
+class ClassOneWithoutStyleError
+{
+    private function foo()
+    {
+        return 'bar';
+    }
+}

tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc

@@ -0,0 +1,20 @@
+<?php
+
+/**
+ * Class containing no style errors.
+ *
+ * @copyright 2025 PHPCSStandards and contributors
+ * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ */
+
+namespace PHP_CodeSniffer\Tests\EndToEnd\Fixtures;
+
+class ClassTwoWithoutStyleError
+{
+    /**
+     * A property.
+     *
+     * @var string
+     */
+    private $bar = 'baz';
+}

tests/EndToEnd/Fixtures/ClassWithStyleError.inc

@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * Class containing a simple style error that phpcbf can fix.
+ *
+ * @copyright 2025 PHPCSStandards and contributors
+ * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ */
+
+namespace PHP_CodeSniffer\Tests\EndToEnd\Fixtures;
+
+class ClassWithStyleError
+{
+    /**
+     * The bracket for this function is misaligned and this can be automatically fixed by phpcbf.
+     *
+     * @return string
+     */
+    private function foo() {
+        return 'bar';
+    }
+}

tests/EndToEnd/Fixtures/endtoend.xml.dist

@@ -0,0 +1,13 @@
+<?xml version="1.0"?>
+<ruleset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" name="EndToEndTests" xsi:noNamespaceSchemaLocation="phpcs.xsd">
+    <description>The coding standard for end to end tests.</description>
+
+    <rule ref="PSR12"/>
+
+    <file>.</file>
+
+    <arg name="basepath" value="."/>
+    <arg name="colors"/>
+    <arg name="parallel" value="75"/>
+    <arg value="p"/>
+</ruleset>

tests/EndToEnd/phpcbf_test.sh

@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+
+function tear_down() {
+  rm -r tests/EndToEnd/Fixtures/*.fixed
+}
+
+function test_phpcbf_is_working() {
+  OUTPUT="$(bin/phpcbf --no-cache --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc)"
+
+  assert_successful_code
+  assert_contains "No violations were found" "$OUTPUT"
+}
+
+function test_phpcbf_is_working_in_parallel() {
+  OUTPUT="$(bin/phpcbf --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc)"
+
+  assert_successful_code
+  assert_contains "No violations were found" "$OUTPUT"
+}
+
+function test_phpcbf_returns_error_on_issues() {
+  OUTPUT="$(bin/phpcbf --no-colors --no-cache --suffix=.fixed --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassWithStyleError.inc)"
+  assert_exit_code 1
+
+  assert_contains "F 1 / 1 (100%)" "$OUTPUT"
+  assert_contains "A TOTAL OF 1 ERROR WERE FIXED IN 1 FILE" "$OUTPUT"
+}
+
+function test_phpcbf_bug_1112() {
+  # See https://github.com/PHPCSStandards/PHP_CodeSniffer/issues/1112
+  if [[ "$(uname)" == "Darwin" ]]; then
+    # Perform some magic with `& fg` to prevent the processes from turning into a background job.
+    assert_successful_code "$(bash -ic 'bash --init-file <(echo "echo \"Subprocess\"") -c "bin/phpcbf --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc" & fg')"
+  else
+    # This is not needed on Linux / GitHub Actions
+    assert_successful_code "$(bash -ic 'bash --init-file <(echo "echo \"Subprocess\"") -c "bin/phpcbf --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc"')"
+  fi
+}

tests/EndToEnd/phpcs_test.sh

@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+
+function test_phpcs_is_working() {
+  assert_successful_code "$(bin/phpcs --no-cache --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc)"
+}
+
+function test_phpcs_is_working_in_parallel() {
+  assert_successful_code "$(bin/phpcs --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc)"
+}
+
+function test_phpcs_returns_error_on_issues() {
+  OUTPUT="$(bin/phpcs --no-colors --no-cache --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassWithStyleError.inc)"
+  assert_exit_code 2
+
+  assert_contains "E 1 / 1 (100%)" "$OUTPUT"
+  assert_contains "FOUND 1 ERROR AFFECTING 1 LINE" "$OUTPUT"
+}
+
+function test_phpcs_bug_1112() {
+  # See https://github.com/PHPCSStandards/PHP_CodeSniffer/issues/1112
+    if [[ "$(uname)" == "Darwin" ]]; then
+      # Perform some magic with `& fg` to prevent the processes from turning into a background job.
+      assert_successful_code "$(bash -ic 'bash --init-file <(echo "echo \"Subprocess\"") -c "bin/phpcs --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc" & fg')"
+    else
+      # This is not needed on Linux / GitHub Actions
+      assert_successful_code "$(bash -ic 'bash --init-file <(echo "echo \"Subprocess\"") -c "bin/phpcs --no-cache --parallel=2 --standard=tests/EndToEnd/Fixtures/endtoend.xml.dist tests/EndToEnd/Fixtures/ClassOneWithoutStyleError.inc tests/EndToEnd/Fixtures/ClassTwoWithoutStyleError.inc"')"
+    fi
+}