Add configurable plugin failure policy

.github/actions/find/README.md

@@ -49,6 +49,15 @@ configuration option.
 Allowlisted NPM plugins use an object with `name`, `package`, and optional `version`. If not provided, only Axe
 will be performed. See [the plugin docs](../../../PLUGINS.md#loading-plugins-from-npm-packages) for an example.
 
+#### `plugin_failure_policy`
+
+**Optional** `log-and-continue` (default) or `abort`. Applies to built-in, local, and NPM plugins, not
+Axe or AccessLint. The default logs scan errors and returns partial findings, preserving existing behavior
+(a thrown plugin error skips the remaining scans on that URL; subsequent URLs still run).
+`abort` rejects failed or unavailable requested plugins, stops subsequent scans and URLs, and writes no
+findings file or output for the run. See [plugin failure behavior](../../../PLUGINS.md#plugin-failure-behavior)
+for limitations.
+
 ### Outputs
 
 #### `findings_file`

.github/actions/find/action.yml

@@ -19,6 +19,10 @@ inputs:
   scans:
     description: "Stringified JSON array of scans to perform. Core engines are 'axe' and 'accesslint'. Any other entry is either a plugin name (string) or, for a first-party NPM-published plugin, an object with 'name', 'package', and optional 'version'. If not provided, only Axe will be performed"
     required: false
+  plugin_failure_policy:
+    description: "Plugin failure behavior: 'log-and-continue' preserves partial findings (default); 'abort' fails before publishing findings when a requested plugin fails or is unavailable. Does not change core engine failure behavior."
+    required: false
+    default: 'log-and-continue'
   reduced_motion:
     description: 'Playwright reducedMotion setting: https://playwright.dev/docs/api/class-browser#browser-new-page-option-reduced-motion'
     required: false

.github/actions/find/src/findForUrl.ts

@@ -17,13 +17,16 @@ import * as core from '@actions/core'
 
 const SELECTOR_WAIT_TIMEOUT = 30000
 
+export type PluginFailurePolicy = 'log-and-continue' | 'abort'
+
 export async function findForUrl(
   urlConfig: UrlConfig,
   authContext?: AuthContext,
   includeScreenshots: boolean = false,
   reducedMotion?: ReducedMotionPreference,
   colorScheme?: ColorSchemePreference,
   ignoreHttpsErrors: boolean = false,
+  pluginFailurePolicy: PluginFailurePolicy = 'log-and-continue',
 ): Promise<Finding[]> {
   const {url, excludeSelectors, waitForSelectors} = urlConfig
   const browser = await playwright.chromium.launch({
@@ -56,13 +59,22 @@ export async function findForUrl(
       findings.push({...findingData, screenshotId, originalUrl: url})
     }
 
+    let pluginStage: string | undefined
     try {
       const scansContext = getScansContext()
 
       if (scansContext.shouldRunPlugins) {
+        pluginStage = 'loading requested plugins'
         const plugins = await loadPlugins()
+        if (pluginFailurePolicy === 'abort') {
+          const unavailable = scansContext.pluginScans.filter(name => !plugins.some(plugin => plugin.name === name))
+          if (unavailable.length > 0) {
+            throw new Error(`Requested plugins are unavailable: ${unavailable.join(', ')}`)
+          }
+        }
         for (const plugin of plugins) {
           if (scansContext.scansToPerform.includes(plugin.name)) {
+            pluginStage = `running plugin '${plugin.name}'`
             core.info(`Running plugin: ${plugin.name}`)
             await invokePlugin({
               plugin,
@@ -73,6 +85,7 @@ export async function findForUrl(
             core.info(`Skipping plugin ${plugin.name} because it is not included in the 'scans' input`)
           }
         }
+        pluginStage = undefined
       }
 
       if (scansContext.shouldPerformAxeScan) {
@@ -84,6 +97,9 @@ export async function findForUrl(
       }
     } catch (e) {
       core.error(`Error during accessibility scan: ${e}`)
+      if (pluginFailurePolicy === 'abort' && pluginStage) {
+        throw new Error(`Plugin failure while ${pluginStage} on ${url}: ${e}`, {cause: e})
+      }
     }
     return findings
   } finally {

.github/actions/find/src/index.ts

@@ -12,6 +12,7 @@ export default async function () {
   const reducedMotion = loadReducedMotion()
   const colorScheme = loadColorScheme()
   const ignoreHttpsErrors = loadIgnoreHttpsErrors()
+  const pluginFailurePolicy = loadPluginFailurePolicy()
 
   const actualUrls = urlConfigs || urls || []
 
@@ -30,6 +31,7 @@ export default async function () {
       reducedMotion,
       colorScheme,
       ignoreHttpsErrors,
+      pluginFailurePolicy,
     )
     if (findingsForUrl.length === 0) {
       core.info(`No accessibility gaps were found on ${url}`)
@@ -120,3 +122,11 @@ function loadColorScheme() {
 function loadIgnoreHttpsErrors() {
   return core.getInput('ignore_https_errors', {required: false}).toLowerCase() === 'true'
 }
+
+function loadPluginFailurePolicy() {
+  const value = core.getInput('plugin_failure_policy', {required: false}) || 'log-and-continue'
+  if (value !== 'log-and-continue' && value !== 'abort') {
+    throw new Error("Input 'plugin_failure_policy' must be one of: 'log-and-continue', 'abort'.")
+  }
+  return value
+}

.github/actions/find/src/scansContextProvider.ts

@@ -4,6 +4,7 @@ import type {NpmPluginRequest} from './pluginManager/types.js'
 type ScansContext = {
   scansToPerform: Array<string>
   npmPlugins: NpmPluginRequest[]
+  pluginScans: string[]
   shouldPerformAxeScan: boolean
   shouldPerformAccesslintScan: boolean
   shouldRunPlugins: boolean
@@ -54,6 +55,7 @@ export function getScansContext() {
     scansContext = {
       scansToPerform,
       npmPlugins,
+      pluginScans,
       // - if no 'scans' input is provided, we default to the existing behavior
       //   (only axe scan) for backwards compatability.
       // - we can enforce using the 'scans' input in a future major release and

.github/actions/find/tests/index.test.ts

@@ -43,7 +43,15 @@ describe('url_configs', () => {
 
     await find()
 
-    expect(mocks.findForUrl).toHaveBeenCalledWith(urlConfig, expect.anything(), false, undefined, undefined, false)
+    expect(mocks.findForUrl).toHaveBeenCalledWith(
+      urlConfig,
+      expect.anything(),
+      false,
+      undefined,
+      undefined,
+      false,
+      'log-and-continue',
+    )
   })
 
   it('rejects waitForSelectors values that are not arrays of strings', async () => {