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Avoid possible race condition issues with loading google and apple pa… #3130

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842f515
Avoid possible race condition issues with loading google and apple pa…
Crabcyborg Jun 8, 2026
4befcb7
Do not wait if google pay / apple pay are disabled
Crabcyborg Jun 8, 2026
9de81eb
Wait for 3 seconds
Crabcyborg Jun 8, 2026
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15 changes: 8 additions & 7 deletions paypal/controllers/FrmPayPalLiteActionsController.php
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Original file line number Diff line number Diff line change
Expand Up @@ -669,9 +669,9 @@

$captures = $payments->captures;

foreach ( $captures as $capture ) {
return $capture->id;
}

Check warning on line 674 in paypal/controllers/FrmPayPalLiteActionsController.php

View workflow job for this annotation

GitHub Actions / Mago

loop-does-not-iterate 

Loop is unconditionally terminated and will not iterate.
>This loop will only execute once at most
>The loop is exited by this unconditional `return` statement

Loops that do not iterate are often misleading and can indicate a logic error or redundant code.

Help: Consider refactoring the code. If the loop is intended to run only once, an `if` statement might be clearer.
}

return '';
Expand Down Expand Up @@ -1409,13 +1409,14 @@
}

$paypal_vars = array(
'formId' => $form_id,
'nonce' => wp_create_nonce( 'frm_paypal_ajax' ),
'ajax' => esc_url_raw( FrmAppHelper::get_ajax_url() ),
'settings' => $action_settings,
'style' => self::get_style_for_js( $form_id ),
'buttonStyle' => self::get_button_style_for_js( $action ),
'imagesUrl' => FrmPayPalLiteAppHelper::plugin_url() . 'images/',
'formId' => $form_id,
'nonce' => wp_create_nonce( 'frm_paypal_ajax' ),
'ajax' => esc_url_raw( FrmAppHelper::get_ajax_url() ),
'settings' => $action_settings,
'style' => self::get_style_for_js( $form_id ),
'buttonStyle' => self::get_button_style_for_js( $action ),
'imagesUrl' => FrmPayPalLiteAppHelper::plugin_url() . 'images/',
'includeGooglePayApplePay' => $include_google_apple_pay,
);

wp_localize_script( 'formidable-paypal', 'frmPayPalVars', $paypal_vars );
Expand Down
307 changes: 210 additions & 97 deletions paypal/js/frontend.js
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Original file line number Diff line number Diff line change
Expand Up @@ -131,13 +131,24 @@
// Clear the card element. We rebuild it entirely.
cardElement.innerHTML = '';

// 1. Discover eligible methods and register them.
// Reset state so each run rediscovers cleanly (the DOM above was cleared).
paymentMethods.clear();
selectedMethod = null;

// 1. Discover synchronous methods (Card, PayPal, alternative funding).
await discoverPaymentMethods( {
cardFieldsAreSupported,
buttonsAreEnabled,
isRecurring
} );

// 1b. Discover Google Pay / Apple Pay. Their SDKs (pay.js / PayPal applepay
// component) load asynchronously and are frequently not ready during the first
// run, which previously left these buttons missing on first load. We wait
// (bounded) for them here so every eligible method appears together in one
// render instead of popping in afterward.
await discoverDeferredPaymentMethods( { buttonsAreEnabled, isRecurring } );
Comment on lines +134 to +150

@coderabbitai coderabbitai Bot Jun 8, 2026

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⚠️ Potential issue | 🟠 Major | 🏗️ Heavy lift

Guard paypalInit() against stale async reruns.

These new deferred awaits create a real interleaving window where an older paypalInit() can resume after a later run has already cleared and rebuilt the shared module state. Because paymentMethods, thisForm, cardFieldsValid, and the SDK caches are all module-scoped, the stale run can register methods into the new registry, append UI against the wrong form state, or re-enable card submit using validity from the previous render. Add a monotonically increasing init token and reset the rest of the per-run globals before the first await.

Suggested direction 
+	let initRunId = 0;
+
 	async function paypalInit() {
+		const runId = ++initRunId;
 		const cardElement = document.querySelector( '.frm-card-element' );
 		if ( ! cardElement ) {
 			return;
 		}
@@
 		// Reset state so each run rediscovers cleanly (the DOM above was cleared).
 		paymentMethods.clear();
 		selectedMethod = null;
+		cardFieldsValid = false;
+		submitEvent = null;
+		googlePayConfig = null;
+		applePayConfig = null;
+		applePayInstance = null;
 
 		// 1. Discover synchronous methods (Card, PayPal, alternative funding).
 		await discoverPaymentMethods( {
 			cardFieldsAreSupported,
 			buttonsAreEnabled,
 			isRecurring
 		} );
+		if ( runId !== initRunId ) {
+			return;
+		}
@@
 		await discoverDeferredPaymentMethods( { buttonsAreEnabled, isRecurring } );
+		if ( runId !== initRunId ) {
+			return;
+		}
+
+		// Apply the same stale-run guard after later awaited init steps that mutate DOM/state.

Also applies to: 294-308

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@paypal/js/frontend.js` around lines 134 - 150, The async interleaving in
paypalInit() can let stale runs mutate module-scoped state (paymentMethods,
thisForm, cardFieldsValid, SDK caches) after a newer run has already reset
things; add a monotonically increasing init token (e.g., module-scoped
initCounter and local runToken) and increment/init it before any awaits, reset
per-run globals (paymentMethods.clear(), selectedMethod=null, thisForm=null,
cardFieldsValid=false, clear relevant SDK caches) immediately before the first
await, then in any async continuations (after await discoverPaymentMethods and
await discoverDeferredPaymentMethods and the other affected block at 294-308)
check that the current module initCounter still equals the runToken and bail out
early if not, ensuring only the latest paypalInit run mutates shared state.


if ( paymentMethods.size === 0 ) {
displayPaymentFailure( 'No payment methods available.' );
return;
Expand Down Expand Up @@ -263,27 +274,117 @@
}
}

// --- Google Pay ---
if ( buttonsAreEnabled && ! isRecurring ) {
const googlePayEligible = await checkGooglePayEligibility();
if ( googlePayEligible ) {
registerMethod( 'google_pay', {
eligible: true,
render: renderGooglePayButton
} );
}
// Google Pay and Apple Pay are discovered separately in
// discoverDeferredPaymentMethods() because their SDKs (pay.js / PayPal applepay
// component) may not be ready yet when this runs.
}

/**
* Discover and register Google Pay and Apple Pay.
*
* Their SDKs load asynchronously and are frequently not ready during the first
* paypalInit() run, which previously caused these buttons to be missing on first
* load and only appear after a page change. We wait (bounded) for each SDK and
* register the eligible methods so they are included when the selector is built.
*
* @param {Object} opts Config flags.
*
* @return {Promise<void>}
*/
async function discoverDeferredPaymentMethods( opts ) {
const { buttonsAreEnabled, isRecurring } = opts;

if ( ! buttonsAreEnabled || isRecurring ) {
return;
}

// --- Apple Pay ---
if ( buttonsAreEnabled && ! isRecurring ) {
const applePayEligibilityResult = await checkApplePayEligibility();
if ( applePayEligibilityResult === '' ) {
registerMethod( 'apple_pay', {
eligible: true,
render: renderApplePayButton
} );
}
// Skip (and avoid the SDK wait) when Google Pay / Apple Pay were not enqueued
// server-side, e.g. via the frm_include_google_pay_apple_pay filter or non-SSL.
if ( ! frmPayPalVars.includeGooglePayApplePay ) {
return;
}

// Resolve both eligibility checks in parallel so the combined wait is bounded by
// the slower of the two, then register them in a fixed order (Google Pay, then
// Apple Pay). Registration happens before the selector is built, so they render
// together with the other methods.
const [ googlePayEligible, applePayEligible ] = await Promise.all( [
resolveGooglePayEligibility(),
resolveApplePayEligibility()
] );

if ( googlePayEligible ) {
registerMethod( 'google_pay', {
eligible: true,
render: renderGooglePayButton
} );
}

if ( applePayEligible ) {
registerMethod( 'apple_pay', {
eligible: true,
render: renderApplePayButton
} );
}
}

/**
* Wait for the Google Pay SDK and resolve whether Google Pay is eligible.
*
* @return {Promise<boolean>} Whether Google Pay is eligible.
*/
async function resolveGooglePayEligibility() {
const sdkReady = await waitFor(
() => 'function' === typeof paypal.Googlepay && 'undefined' !== typeof google && undefined !== google.payments
);
if ( ! sdkReady ) {
return false;
}

return checkGooglePayEligibility();
}

/**
* Wait for the Apple Pay SDK and resolve whether Apple Pay is eligible.
*
* @return {Promise<boolean>} Whether Apple Pay is eligible.
*/
async function resolveApplePayEligibility() {
const sdkReady = await waitFor( () => 'function' === typeof paypal.Applepay );
if ( ! sdkReady ) {
return false;
}

return '' === await checkApplePayEligibility();
}

/**
* Poll for a condition until it is true or a timeout elapses.
*
* @param {Function} predicate Returns true when the awaited dependency is ready.
* @param {number} [timeout] Maximum time to wait, in milliseconds.
* @param {number} [interval] Poll interval, in milliseconds.
*
* @return {Promise<boolean>} Whether the predicate became true before the timeout.
*/
function waitFor( predicate, timeout = 3000, interval = 50 ) {
return new Promise( resolve => {
if ( predicate() ) {
resolve( true );
return;
}

const start = Date.now();
const timer = setInterval( () => {
if ( predicate() ) {
clearInterval( timer );
resolve( true );
} else if ( Date.now() - start >= timeout ) {
clearInterval( timer );
resolve( false );
}
}, interval );
} );
}

/**
Expand Down Expand Up @@ -319,89 +420,101 @@
group.setAttribute( 'aria-label', 'Select payment method' );

for ( const [ key, method ] of paymentMethods ) {
const label = document.createElement( 'label' );
label.classList.add( 'frm-payment-method-option' );
label.setAttribute( 'for', `frm-payment-method-radio-${ key }` );

const radio = document.createElement( 'input' );
radio.type = 'radio';
radio.name = 'frm_payment_method';
radio.id = `frm-payment-method-radio-${ key }`;
radio.value = key;

radio.addEventListener( 'change', () => selectPaymentMethod( key ) );

// Text column: label + description.
const textWrap = document.createElement( 'div' );
textWrap.classList.add( 'frm-payment-method-text' );

const labelText = document.createElement( 'span' );
labelText.classList.add( 'frm-payment-method-label-text' );
labelText.textContent = method.label;
textWrap.append( labelText );

// Mark column: will be populated by renderMarks() after the group is in the DOM.
const markWrap = document.createElement( 'div' );
markWrap.classList.add( 'frm-payment-method-mark' );
markWrap.id = `frm-payment-mark-${ key }`;

const baseUrl = frmPayPalVars.imagesUrl || '';

if ( key === 'card' ) {
const cardBrands = [
{ file: 'visa.svg', alt: 'Visa' },
{ file: 'mastercard.svg', alt: 'Mastercard' },
{ file: 'amex.svg', alt: 'American Express' },
{ file: 'discover.svg', alt: 'Discover' },
];
cardBrands.forEach( function( brand ) {
const img = document.createElement( 'img' );
img.src = baseUrl + brand.file;
img.alt = brand.alt;
img.height = 24;
markWrap.append( img );
} );
} else if ( key === 'google_pay' ) {
markWrap.classList.add( 'frm-payment-method-google-pay-icon' );
const img = document.createElement( 'img' );
img.src = `${ baseUrl }gpay.svg`;
img.alt = 'Google Pay';
img.height = 24;
markWrap.append( img );
} else if ( key === 'apple_pay' ) {
markWrap.classList.add( 'frm-payment-method-apple-pay-icon' );
const img = document.createElement( 'img' );
img.src = `${ baseUrl }apple-pay.svg`;
img.alt = 'Apple Pay';
img.height = 24;
img.style.width = 'auto';
markWrap.append( img );
}

label.append( radio );
label.append( textWrap );
label.append( markWrap );

if ( key === 'paylater' ) {
// Wrap the label and a message container in a div.
const wrapper = document.createElement( 'div' );
wrapper.classList.add( 'frm-payment-method-paylater-wrap' );
wrapper.append( label );

const msgContainer = document.createElement( 'div' );
msgContainer.id = 'frm-paylater-message';
msgContainer.classList.add( 'frm-payment-method-paylater-msg' );
wrapper.append( msgContainer );

group.append( wrapper );
} else {
group.append( label );
}
group.append( buildMethodOption( key, method ) );
}

return group;
}

/**
* Build a single payment method radio option row.
*
* @param {string} key The payment method key.
* @param {Object} method The registered method object.
*
* @return {HTMLElement} The option element (a label, or a wrapper for Pay Later).
*/
function buildMethodOption( key, method ) {
const label = document.createElement( 'label' );
label.classList.add( 'frm-payment-method-option' );
label.setAttribute( 'for', `frm-payment-method-radio-${ key }` );

const radio = document.createElement( 'input' );
radio.type = 'radio';
radio.name = 'frm_payment_method';
radio.id = `frm-payment-method-radio-${ key }`;
radio.value = key;

radio.addEventListener( 'change', () => selectPaymentMethod( key ) );

// Text column: label + description.
const textWrap = document.createElement( 'div' );
textWrap.classList.add( 'frm-payment-method-text' );

const labelText = document.createElement( 'span' );
labelText.classList.add( 'frm-payment-method-label-text' );
labelText.textContent = method.label;
textWrap.append( labelText );

// Mark column: will be populated by renderMarks() after the group is in the DOM.
const markWrap = document.createElement( 'div' );
markWrap.classList.add( 'frm-payment-method-mark' );
markWrap.id = `frm-payment-mark-${ key }`;

const baseUrl = frmPayPalVars.imagesUrl || '';

if ( key === 'card' ) {
const cardBrands = [
{ file: 'visa.svg', alt: 'Visa' },
{ file: 'mastercard.svg', alt: 'Mastercard' },
{ file: 'amex.svg', alt: 'American Express' },
{ file: 'discover.svg', alt: 'Discover' },
];
cardBrands.forEach( function( brand ) {
const img = document.createElement( 'img' );
img.src = baseUrl + brand.file;
img.alt = brand.alt;
img.height = 24;
markWrap.append( img );
} );
} else if ( key === 'google_pay' ) {
markWrap.classList.add( 'frm-payment-method-google-pay-icon' );
const img = document.createElement( 'img' );
img.src = `${ baseUrl }gpay.svg`;
img.alt = 'Google Pay';
img.height = 24;
markWrap.append( img );
} else if ( key === 'apple_pay' ) {
markWrap.classList.add( 'frm-payment-method-apple-pay-icon' );
const img = document.createElement( 'img' );
img.src = `${ baseUrl }apple-pay.svg`;
img.alt = 'Apple Pay';
img.height = 24;
img.style.width = 'auto';
markWrap.append( img );
}

label.append( radio );
label.append( textWrap );
label.append( markWrap );

if ( key === 'paylater' ) {
// Wrap the label and a message container in a div.
const wrapper = document.createElement( 'div' );
wrapper.classList.add( 'frm-payment-method-paylater-wrap' );
wrapper.append( label );

const msgContainer = document.createElement( 'div' );
msgContainer.id = 'frm-paylater-message';
msgContainer.classList.add( 'frm-payment-method-paylater-msg' );
wrapper.append( msgContainer );

return wrapper;
}

return label;
}

/**
* Render PayPal Marks into the radio group containers.
* Must be called AFTER the radio group is appended to the DOM,
Expand Down
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