fix(phpunit): scope file-only testsuites to declared files

packages/runtime-playground/src/phpunit-command-handlers.ts

@@ -180,6 +180,8 @@ function phpunitConfigDiscoveryPhp(options: PhpunitConfigDiscoveryPhpOptions): s
     if (!empty($config_dirs)) {
         $directories = $config_dirs;
         ${options.logFunction}('${options.loadedConfigMessage}' . $xml_path);
+    } elseif (!empty($files)) {
+        $directories = array();
     }
     if (!empty($config_suffixes)) {
         ${suffixAssignment}

tests/phpunit-discovery-only.test.ts

@@ -1,11 +1,41 @@
 import assert from "node:assert/strict"
 import test from "node:test"
+import { execFileSync } from "node:child_process"
+import { mkdirSync, mkdtempSync, writeFileSync } from "node:fs"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
 import { buildWordPressPhpunitRecipe } from "../packages/runtime-core/src/recipe-builders.js"
 import { phpunitRunCode } from "../packages/runtime-playground/src/phpunit-command-handlers.js"
 import { runPhpunitCommand } from "../packages/runtime-playground/src/wordpress-command-runners.js"
 import { recipeHasPhpunitDiscoveryOnly } from "../packages/cli/src/commands/recipe-runtime-setup.js"
 import { wordpressRuntimeSpec } from "../scripts/test-kit.js"
 
+function extractPhpFunction(source: string, functionName: string): string {
+  const start = source.indexOf(`function ${functionName}(`)
+  assert.notEqual(start, -1, `expected generated PHP to declare ${functionName}`)
+
+  let depth = 0
+  let sawBody = false
+  for (let index = start; index < source.length; index++) {
+    const character = source[index]
+    if (character === "{") {
+      depth++
+      sawBody = true
+    } else if (character === "}") {
+      depth--
+      if (sawBody && depth === 0) {
+        return source.slice(start, index + 1)
+      }
+    }
+  }
+
+  throw new Error(`Could not extract PHP function ${functionName}`)
+}
+
+function phpString(value: string): string {
+  return `'${value.replace(/\\/g, "\\\\").replace(/'/g, "\\'")}'`
+}
+
 test("wordpress.phpunit discovery-only returns canonical files before execution", () => {
   const recipe = buildWordPressPhpunitRecipe({
     pluginSlug: "fixture",
@@ -93,3 +123,130 @@ test("recipe setup uses canonical boolean parsing and rejects mixed workflows",
   recipe.workflow.after = [{ command: "wordpress.wp-cli", args: ["command=plugin list"] }]
   assert.throws(() => recipeHasPhpunitDiscoveryOnly(recipe), /must be the recipe's sole workflow step/)
 })
+
+// Regression coverage for https://github.com/Automattic/wp-codebox/issues/2516.
+//
+// This exercises the *default* discovery path (no --testsuite selection), which is the path
+// PHPUnit discovery actually runs on and the path the production bug lived in. It is distinct
+// from the `selected_testsuites` coverage in tests/phpunit-project-autoload.test.ts, where
+// `$directories` is unconditionally reset to `array()` before config parsing and was never
+// affected by this bug.
+test("file-only testsuite discovery (issue #2516)", async (t) => {
+  const code = phpunitRunCode({
+    pluginSlug: "fixture",
+    cwd: "/wordpress/wp-content/plugins/fixture",
+    autoloadFile: "/wp-codebox-vendor/autoload.php",
+    testsDir: "/wp-codebox-vendor/wp-phpunit/wp-phpunit",
+    testRoot: "/wordpress/wp-content/plugins/fixture/tests",
+    phpunitXml: "/wordpress/wp-content/plugins/fixture/phpunit.xml.dist",
+    phpunitXmlIsDefault: false,
+    selectedTestFile: "",
+    changedTestFiles: [],
+    phpunitArgs: [],
+    env: {},
+    wpConfigDefines: {},
+    dependencyMounts: [],
+    bootstrapFiles: [],
+    bootstrapMode: "managed",
+    projectBootstrap: "",
+    multisite: false,
+    databaseType: "sqlite",
+  })
+
+  const parseConfigFunction = extractPhpFunction(code, "wp_codebox_phpunit_parse_config")
+  const discoverFunction = extractPhpFunction(code, "wp_codebox_phpunit_discover")
+
+  // Tree shape mirrors the production report: a whole test root containing a file matching the
+  // default `*Test.php` suffix that no suite declares, plus per-suite subdirectories.
+  const tempDir = mkdtempSync(join(tmpdir(), "wp-codebox-phpunit-2516-"))
+  const testsDir = join(tempDir, "tests")
+  mkdirSync(join(testsDir, "booking"), { recursive: true })
+  mkdirSync(join(testsDir, "dir-suite"), { recursive: true })
+  writeFileSync(join(testsDir, "UnrelatedTest.php"), "<?php final class UnrelatedTest extends TestCase {}\n")
+  writeFileSync(join(testsDir, "booking", "DeclaredTest.php"), "<?php final class DeclaredTest extends TestCase {}\n")
+  writeFileSync(join(testsDir, "dir-suite", "ScopedTest.php"), "<?php final class ScopedTest extends TestCase {}\n")
+
+  const fileOnlyXml = join(tempDir, "file-only.xml")
+  writeFileSync(
+    fileOnlyXml,
+    `<phpunit><testsuites><testsuite name="booking-alpha-concurrency"><file>tests/booking/DeclaredTest.php</file></testsuite></testsuites></phpunit>`,
+  )
+
+  const directoryXml = join(tempDir, "directory.xml")
+  writeFileSync(
+    directoryXml,
+    `<phpunit><testsuites><testsuite name="managed-wordpress"><directory>tests/dir-suite</directory></testsuite></testsuites></phpunit>`,
+  )
+
+  const neitherXml = join(tempDir, "neither.xml")
+  writeFileSync(neitherXml, `<phpunit><testsuites><testsuite name="empty"></testsuite></testsuites></phpunit>`)
+
+  await t.test("case: only <file> declared runs exactly that file, no directory scan (the fix)", () => {
+    const scriptPath = join(tempDir, "case-file-only.php")
+    writeFileSync(
+      scriptPath,
+      `<?php
+function pg_log($message) {}
+${parseConfigFunction}
+${discoverFunction}
+list($directories, $suffixes, $prefixes, $excludes, $files) = wp_codebox_phpunit_parse_config(${phpString(fileOnlyXml)}, ${phpString(testsDir)});
+if ($directories !== array()) {
+    throw new RuntimeException('file-only testsuite must not fall back to the whole test root: ' . json_encode($directories));
+}
+$discovered = wp_codebox_phpunit_discover($directories, $suffixes, $prefixes, $excludes, $files);
+if ($discovered !== array(${phpString(join(testsDir, "booking", "DeclaredTest.php"))})) {
+    throw new RuntimeException('file-only testsuite swept in unrelated files: ' . json_encode($discovered));
+}
+echo "ok\\n";
+`,
+    )
+    assert.equal(execFileSync("php", [scriptPath], { encoding: "utf8" }), "ok\n")
+  })
+
+  await t.test("case: <directory> declared stays scoped to it (unchanged)", () => {
+    const scriptPath = join(tempDir, "case-directory.php")
+    writeFileSync(
+      scriptPath,
+      `<?php
+function pg_log($message) {}
+${parseConfigFunction}
+${discoverFunction}
+list($directories, $suffixes, $prefixes, $excludes, $files) = wp_codebox_phpunit_parse_config(${phpString(directoryXml)}, ${phpString(testsDir)});
+if ($directories !== array(${phpString(join(testsDir, "dir-suite"))})) {
+    throw new RuntimeException('directory-declaring testsuite must be unaffected by this fix: ' . json_encode($directories));
+}
+$discovered = wp_codebox_phpunit_discover($directories, $suffixes, $prefixes, $excludes, $files);
+if ($discovered !== array(${phpString(join(testsDir, "dir-suite", "ScopedTest.php"))})) {
+    throw new RuntimeException('directory-declaring testsuite discovery changed: ' . json_encode($discovered));
+}
+echo "ok\\n";
+`,
+    )
+    assert.equal(execFileSync("php", [scriptPath], { encoding: "utf8" }), "ok\n")
+  })
+
+  await t.test("case: neither <directory> nor <file> keeps the whole-test-root default (unchanged)", () => {
+    const scriptPath = join(tempDir, "case-neither.php")
+    writeFileSync(
+      scriptPath,
+      `<?php
+function pg_log($message) {}
+${parseConfigFunction}
+${discoverFunction}
+list($directories, $suffixes, $prefixes, $excludes, $files) = wp_codebox_phpunit_parse_config(${phpString(neitherXml)}, ${phpString(testsDir)});
+if ($directories !== array(${phpString(testsDir)})) {
+    throw new RuntimeException('config declaring neither <directory> nor <file> must keep the whole-test-root default: ' . json_encode($directories));
+}
+$discovered = wp_codebox_phpunit_discover($directories, $suffixes, $prefixes, $excludes, $files);
+sort($discovered);
+$expected = array(${phpString(join(testsDir, "UnrelatedTest.php"))}, ${phpString(join(testsDir, "booking", "DeclaredTest.php"))}, ${phpString(join(testsDir, "dir-suite", "ScopedTest.php"))});
+sort($expected);
+if ($discovered !== $expected) {
+    throw new RuntimeException('whole-test-root discovery changed for a config declaring neither: ' . json_encode($discovered));
+}
+echo "ok\\n";
+`,
+    )
+    assert.equal(execFileSync("php", [scriptPath], { encoding: "utf8" }), "ok\n")
+  })
+})