fix: build Playwright UI bundles as declared Bazel outputs

docs/ui.md

@@ -34,12 +34,20 @@ entries recursively; specify those entries rather than relying on implicit
 package-wide test discovery. Bazel `test_suite` tag filtering is not applied by
 UI aggregation: every explicitly listed managed E2E target is selected.
 
-The rule selects compiled specs from each suite and includes their dependencies
-and explicit data. Duplicate specs appear once. At launch, it writes a temporary
-aggregate config that discovers exactly those specs. Source maps and original
-source inputs are retained for debugging. Temporary configuration is removed
-when Playwright exits. The UI process runs until closed and receives terminal
-interrupts; it has no suite execution timer.
+Bazel selects and deduplicates compiled specs during analysis. Declared actions
+build an immutable directory artifact containing the aggregate config and import
+modules for exactly those specs. A generated `js_binary` entry point starts the
+declared Playwright CLI directly with Bazel's Node toolchain. No session-time
+config generation, temporary spec copies, or workspace package-manager lookup.
+
+The UI watches only the bundle's spec directory. It cannot recursively watch
+neighboring Bazel outputs and runfiles, which exhausted macOS file descriptors
+and caused `spawn EBADF` when workers started. Specs execute at their original
+compiled locations, retaining relative imports, source maps, and debugger inputs.
+
+Test artifacts use the caller's configured output directory or default to
+`test-results/<package>/<target>` under the workspace. Bazel tests use their
+output/temp directory instead. The bundle itself is never modified by the UI.
 
 Supply one aggregate compiled config, including browser settings and a shared
 `webServer` if needed. Individual suite configs and environment variables are
@@ -50,28 +58,14 @@ working directory. Declare extra server dependencies in `data` and values in
 Specs and config must resolve the same `@playwright/test` instance as the declared
 runtime, matching the regular test rule's package contract.
 
-Compiled mode displays the emitted JavaScript executed by CI. Watching workspace
-TypeScript does not rebuild Bazel outputs automatically. Rebuild/relaunch after
-source edits, or use source mode for the live edit/watch workflow.
-
-## Workspace source mode
-
-```starlark
-web_e2e_ui(
-    name = "e2e_ui_source",
-    suites = [":e2e_tests"],
-    mode = "source",
-    source_config = "playwright.source.config.ts",
-)
-```
+The UI displays the emitted JavaScript executed by CI. Rebuild/relaunch after
+TypeScript edits. `mode = "source"` and `source_config` are no longer supported;
+this rule uses declared compiled suites and the declared Playwright runtime only.
 
-Source mode runs the caller's original config from `BUILD_WORKSPACE_DIRECTORY`.
-That config owns source test discovery, TypeScript aliases, server startup, and
-watch behavior. Configure it to discover the same feature specs selected by the
-suite list. It uses the workspace's installed `@playwright/test`, so run the
-workspace package-manager setup first. It inherits the developer's environment
-and browser installation. It deliberately runs outside hermetic test actions;
-source discovery is not constrained to the compiled suite selection.
+Managed-server E2E suites are supported. Component, visual, and process-owned
+suites require different runtime contracts and are rejected.
 
-Both modes currently support managed-server E2E suites. Component, visual, and
-process-owned suites require different runtime contracts and are rejected.
+On Linux without `DISPLAY` or `WAYLAND_DISPLAY`, the launcher serves the UI on
+loopback and prints its URL instead of opening a headed browser. Forward that
+port from your devbox and open it locally. Explicit `--ui-host` and `--ui-port`
+options override the default.

internal/BUILD.bazel

@@ -1,7 +1,11 @@
+load("@aspect_rules_js//js:defs.bzl", "js_binary")
 load(":remote.bzl", "linux_platform")
 
 exports_files([
     "capture-launcher.sh.tpl",
+    "ui-config.mjs.tpl",
+    "ui-runfiles.mjs.tpl",
+    "ui-launcher.mjs.tpl",
     "browser.bzl",
     "snapshots.bzl",
     "matching.bzl",
@@ -31,4 +35,14 @@ linux_platform(
     target_compatible_with = ["@platforms//os:linux"],
 )
 
-exports_files(["matching-config.ts"], visibility = ["//visibility:private"])
+exports_files(
+    ["matching-config.ts"],
+    visibility = ["//visibility:private"],
+)
+
+js_binary(
+    name = "ui_wrapper_tool",
+    entry_point = "ui-wrapper-tool.mjs",
+    patch_node_fs = False,
+    visibility = ["//visibility:private"],
+)

internal/ui-config.mjs.tpl

@@ -0,0 +1,33 @@
+import fs from 'node:fs'
+import os from 'node:os'
+import path from 'node:path'
+import {fileURLToPath} from 'node:url'
+import {importModule, resolveRunfile} from './runfiles.mjs'
+
+const configFile = fs.realpathSync(resolveRunfile(%{config}))
+const {default: config} = await importModule(%{config})
+const originalDirectory = path.dirname(configFile)
+const selection = {
+  testDir: path.join(path.dirname(fileURLToPath(import.meta.url)), 'specs'),
+  testMatch: '**/*.js',
+  testIgnore: [],
+}
+const reportRoot = path.resolve(path.dirname(fs.realpathSync(resolveRunfile(%{root_anchor}))), %{root_up})
+const resultsRoot = process.env.TEST_UNDECLARED_OUTPUTS_DIR || process.env.TEST_TMPDIR || process.env.BUILD_WORKSPACE_DIRECTORY || os.tmpdir()
+const outputDir = config.outputDir ? path.resolve(originalDirectory, config.outputDir) : path.join(resultsRoot, 'test-results', %{output_path})
+const servers = config.webServer ? (Array.isArray(config.webServer) ? config.webServer : [config.webServer]).map(server => ({
+  ...server, cwd: server.cwd ?? originalDirectory,
+})) : undefined
+
+export default {
+  ...config,
+  ...selection,
+  testDir: reportRoot,
+  outputDir,
+  webServer: servers,
+  projects: (config.projects ?? [{}]).map(project => ({
+    ...project,
+    ...selection,
+    outputDir: project.outputDir ? path.resolve(originalDirectory, project.outputDir) : outputDir,
+  })),
+}

internal/ui-launcher.mjs.tpl

@@ -0,0 +1,18 @@
+import path from 'node:path'
+import {pathToFileURL} from 'node:url'
+
+const root = process.env.RUNFILES_DIR || process.env.JS_BINARY__RUNFILES
+if (!root) throw new Error('Playwright UI requires Bazel runfiles')
+const bundle = path.join(root, %{bundle})
+const {playwrightCli} = await import(pathToFileURL(path.join(bundle, 'runfiles.mjs')).href)
+const args = process.argv.slice(2)
+const serverOnly = process.platform === 'linux' && !process.env.DISPLAY && !process.env.WAYLAND_DISPLAY
+if (serverOnly && !args.includes('--list') && !args.includes('--help') && !args.some(arg => /^--ui-(host|port)(=|$)/.test(arg)))
+  args.push('--ui-host=127.0.0.1')
+process.chdir(path.join(root, process.env.JS_BINARY__WORKSPACE || '_main'))
+process.argv = [
+  process.execPath, playwrightCli, 'test', '--config', path.join(bundle, 'playwright.config.mjs'),
+  ...(!args.includes('--list') && !args.includes('--help') && !args.includes('--ui') ? ['--ui'] : []),
+  ...args,
+]
+await import(pathToFileURL(playwrightCli).href)

internal/ui-runfiles.mjs.tpl

@@ -0,0 +1,22 @@
+import fs from 'node:fs'
+import path from 'node:path'
+import {createRequire} from 'node:module'
+import {pathToFileURL} from 'node:url'
+
+const root = process.env.RUNFILES_DIR || process.env.JS_BINARY__RUNFILES
+if (!root) throw new Error('Playwright UI requires Bazel runfiles')
+
+export function resolveRunfile(relative) {
+  return path.join(root, relative)
+}
+
+const testPackage = path.dirname(fs.realpathSync(path.join(resolveRunfile(%{playwright}), 'package.json')))
+export const playwrightCli = path.join(testPackage, 'cli.js')
+
+export async function importModule(relative) {
+  const file = fs.realpathSync(resolveRunfile(relative))
+  const resolved = createRequire(pathToFileURL(file)).resolve('@playwright/test/package.json')
+  if (path.dirname(fs.realpathSync(resolved)) !== testPackage)
+    throw new Error('UI specs and config must resolve the declared playwright runtime: ' + file)
+  return import(pathToFileURL(file).href)
+}

internal/ui-wrapper-tool.mjs

@@ -0,0 +1,19 @@
+import fs from 'node:fs'
+import path from 'node:path'
+
+process.chdir(process.env.JS_BINARY__EXECROOT)
+for (const spec of JSON.parse(fs.readFileSync(process.argv[2], 'utf8'))) {
+  const content = fs.readFileSync(spec.input, 'utf8')
+  const reference = [...content.matchAll(/\/\/# sourceMappingURL=(.+)/g)].at(-1)?.[1].trim()
+  let sources = [spec.input]
+  if (reference) {
+    const inline = reference.startsWith('data:')
+    const mapFile = inline ? spec.input : path.join(path.dirname(spec.input), reference)
+    const map = JSON.parse(inline ? Buffer.from(reference.split(',')[1], 'base64').toString() : fs.readFileSync(mapFile, 'utf8'))
+    sources = map.sources.map(source => path.join(path.dirname(mapFile), map.sourceRoot || '', source))
+  }
+  // UI file filters use source locations; imported specs keep their own mappings.
+  const map = {version: 3, sources: sources.map(source => path.relative(path.dirname(spec.destination), source)), names: [], mappings: ''}
+  const encoded = Buffer.from(JSON.stringify(map)).toString('base64')
+  fs.writeFileSync(spec.output, `import { importModule } from ${JSON.stringify(spec.helper)};\nawait importModule(${JSON.stringify(spec.runfile)});\n//# sourceMappingURL=data:application/json;base64,${encoded}\n`)
+}

internal/ui.bzl

@@ -1,7 +1,8 @@
-"""Aggregate browser suites for local Playwright development."""
+"""Aggregate browser suites into a declared Playwright UI bundle."""
 
 load("@aspect_rules_js//js:defs.bzl", "js_binary")
-load("@bazel_lib//lib:paths.bzl", "to_rlocation_path")
+load("@bazel_lib//lib:copy_to_directory.bzl", "copy_to_directory_bin_action")
+load("@bazel_lib//lib:paths.bzl", "to_repository_relative_path", "to_rlocation_path")
 load("//playwright:defs.bzl", "PlaywrightInfo")
 
 BrowserSuiteInfo = provider(fields = ["tests", "runfiles", "mode"])
@@ -21,6 +22,15 @@ def _suites_impl(target, ctx):
 
 _suites = aspect(implementation = _suites_impl, attr_aspects = ["data", "tests"])
 
+def _common_directory(files):
+    parts = [file.path.split("/")[:-1] for file in files]
+    common = []
+    for i in range(min([len(value) for value in parts])):
+        if any([value[i] != parts[0][i] for value in parts]):
+            break
+        common.append(parts[0][i])
+    return common
+
 def _inputs_impl(ctx):
     tests = []
     runfiles = ctx.runfiles()
@@ -36,59 +46,116 @@ def _inputs_impl(ctx):
     tests = depset(tests).to_list()
     if not tests:
         fail("suites must select at least one compiled spec")
-    if ctx.attr.mode == "compiled":
-        if not ctx.attr.config:
-            fail("compiled mode requires an aggregate config")
-        config_files = [file for file in ctx.files.config if file.extension in ["js", "mjs"]]
-        if len(config_files) != 1 or config_files[0].is_source:
-            fail("config must supply one compiled JavaScript module")
-        config = to_rlocation_path(ctx, config_files[0])
-        runfiles = runfiles.merge(ctx.attr.config[DefaultInfo].default_runfiles).merge(ctx.runfiles(files = ctx.files.config))
-    else:
-        if not ctx.file.source_config or not ctx.file.source_config.is_source or ctx.file.source_config.short_path.startswith("../"):
-            fail("source mode requires a workspace source_config")
-        config = ctx.file.source_config.short_path
+    config_files = [file for file in ctx.files.config if file.extension in ["js", "mjs"]]
+    if len(config_files) != 1 or config_files[0].is_source:
+        fail("config must supply one compiled JavaScript module")
     runtime = ctx.attr.playwright[PlaywrightInfo]
-    manifest = ctx.actions.declare_file(ctx.label.name + ".json")
-    ctx.actions.write(manifest, json.encode({
-        "mode": ctx.attr.mode,
-        "config": config,
-        "tests": [to_rlocation_path(ctx, file) for file in tests],
-        "playwright": runtime.test,
-    }))
-    for target in [ctx.attr.playwright] + ctx.attr.data:
+    bundle = ctx.actions.declare_directory(ctx.label.name + ".suite")
+    generated = []
+    destinations = {}
+    wrappers = []
+    for file in tests:
+        destination = "specs/" + to_rlocation_path(ctx, file) + ".js"
+        wrapper = ctx.actions.declare_file(ctx.label.name + ".generated/" + destination)
+        helper = "../" * (len(destination.split("/")) - 1) + "runfiles.mjs"
+        wrappers.append({
+            "input": file.path,
+            "output": wrapper.path,
+            "destination": bundle.path + "/" + destination,
+            "helper": helper,
+            "runfile": to_rlocation_path(ctx, file),
+        })
+        generated.append(wrapper)
+        destinations[to_repository_relative_path(wrapper)] = destination
+    manifest = ctx.actions.declare_file(ctx.label.name + ".wrappers.json")
+    ctx.actions.write(manifest, json.encode(wrappers))
+    ctx.actions.run(
+        executable = ctx.executable._wrapper_tool,
+        arguments = [manifest.path],
+        inputs = depset([manifest] + tests + [file for file in runfiles.files.to_list() if file.path.endswith(".map")]),
+        outputs = generated[:],
+        env = {"BAZEL_BINDIR": ctx.bin_dir.path},
+        mnemonic = "PlaywrightUiWrappers",
+    )
+    package = ctx.actions.declare_file(ctx.label.name + ".generated/package.json")
+    ctx.actions.write(package, '{"type":"module"}')
+    generated.append(package)
+    destinations[to_repository_relative_path(package)] = "package.json"
+    root_up = "/".join([".."] * (len(tests[0].path.split("/")) - 1 - len(_common_directory(tests)))) or "."
+    substitutions = {
+        "%{config}": json.encode(to_rlocation_path(ctx, config_files[0])),
+        "%{playwright}": json.encode(runtime.test),
+        "%{root_anchor}": json.encode(to_rlocation_path(ctx, tests[0])),
+        "%{root_up}": json.encode(root_up),
+        "%{output_path}": json.encode(ctx.label.package + "/" + ctx.attr.output_name),
+    }
+    for template, destination in [
+        (ctx.file._config_template, "playwright.config.mjs"),
+        (ctx.file._runfiles_template, "runfiles.mjs"),
+    ]:
+        output = ctx.actions.declare_file(ctx.label.name + ".generated/" + destination)
+        ctx.actions.expand_template(template = template, output = output, substitutions = substitutions)
+        generated.append(output)
+        destinations[to_repository_relative_path(output)] = destination
+
+    # Playwright ignores individually symlinked specs. A tree artifact contains real
+    # files and bounds directory watching to the selected specs, not Bazel runfiles.
+    copy_to_directory_bin_action(
+        ctx,
+        name = ctx.label.name,
+        dst = bundle,
+        copy_to_directory_bin = ctx.toolchains["@bazel_lib//lib:copy_to_directory_toolchain_type"].copy_to_directory_info.bin,
+        files = generated,
+        root_paths = [],
+        include_external_repositories = ["**"],
+        replace_prefixes = destinations,
+        hardlink = "off",
+    )
+    launcher = ctx.actions.declare_file(ctx.label.name + ".mjs")
+    ctx.actions.expand_template(
+        template = ctx.file._launcher_template,
+        output = launcher,
+        substitutions = {"%{bundle}": json.encode(to_rlocation_path(ctx, bundle))},
+    )
+    for target in [ctx.attr.config, ctx.attr.playwright] + ctx.attr.data:
         runfiles = runfiles.merge(target[DefaultInfo].default_runfiles).merge(ctx.runfiles(transitive_files = target[DefaultInfo].files))
-    return [DefaultInfo(files = depset([manifest]), runfiles = runfiles.merge(ctx.runfiles(files = [manifest])))]
+    return [
+        DefaultInfo(files = depset([launcher]), runfiles = runfiles.merge(ctx.runfiles(files = [launcher, bundle]))),
+        OutputGroupInfo(ui_bundle = depset([bundle])),
+    ]
 
 _inputs = rule(
     implementation = _inputs_impl,
     attrs = {
         "suites": attr.label_list(mandatory = True, aspects = [_suites]),
-        "config": attr.label(allow_files = True),
-        "source_config": attr.label(allow_single_file = True),
-        "mode": attr.string(default = "compiled", values = ["compiled", "source"]),
+        "config": attr.label(mandatory = True, allow_files = True),
         "playwright": attr.label(mandatory = True, providers = [PlaywrightInfo]),
         "data": attr.label_list(allow_files = True),
+        "output_name": attr.string(mandatory = True),
+        "_wrapper_tool": attr.label(default = Label("//internal:ui_wrapper_tool"), executable = True, cfg = "exec"),
+        "_config_template": attr.label(default = Label("//internal:ui-config.mjs.tpl"), allow_single_file = True),
+        "_runfiles_template": attr.label(default = Label("//internal:ui-runfiles.mjs.tpl"), allow_single_file = True),
+        "_launcher_template": attr.label(default = Label("//internal:ui-launcher.mjs.tpl"), allow_single_file = True),
     },
+    toolchains = ["@bazel_lib//lib:copy_to_directory_toolchain_type"],
 )
 
-def web_e2e_ui(name, suites, config = None, source_config = None, mode = "compiled", playwright = Label("//runtime:playwright"), data = [], env = {}, args = [], visibility = None):
-    """Launch one local UI session over existing E2E suites with a shared config."""
+def web_e2e_ui(name, suites, config, playwright = Label("//runtime:playwright"), data = [], env = {}, args = [], visibility = None):
+    """Build an aggregate UI bundle and run it with declared Node and Playwright."""
     _inputs(
         name = name + "_ui_inputs",
         suites = depset(suites).to_list(),
         config = config,
-        source_config = source_config,
-        mode = mode,
         playwright = playwright,
         data = data,
+        output_name = name,
         testonly = True,
     )
     js_binary(
         name = name,
-        entry_point = Label("//runtime:ui_entry"),
-        data = [":" + name + "_ui_inputs", Label("//runtime:ui_files")] + data,
-        env = env | {"WEB_E2E_UI_INPUTS": "$(rlocationpath :%s_ui_inputs)" % name},
+        entry_point = ":" + name + "_ui_inputs",
+        data = [":" + name + "_ui_inputs"] + data,
+        env = env,
         args = args,
         patch_node_fs = False,
         copy_data_to_bin = False,

runtime/BUILD.bazel

@@ -111,25 +111,6 @@ filegroup(
     visibility = ["//visibility:public"],
 )
 
-filegroup(
-    name = "ui_entry",
-    srcs = ["ui.js"],
-    visibility = ["//visibility:public"],
-)
-
-js_library(
-    name = "ui_files",
-    srcs = ["ui.js", "package.json"],
-    visibility = ["//visibility:public"],
-)
-
-js_test(
-    name = "ui_test",
-    size = "small",
-    data = ["package.json", ":test_typecheck"],
-    entry_point = "ui.test.js",
-)
-
 js_library(
     name = "remote_result_files",
     srcs = ["remote-result.js", "baselines.js", "package.json"],