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[ci] Run CI for #3372 (Date subclassing fix) #3419

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8283e83
test: add failing test for Date subclassing in workflow VM
ar-tama Aug 6, 2026
58bc5d0
fix(core): preserve `new.target` in the deterministic `Date` override…
ar-tama Aug 6, 2026
4601046
test: add failing test for calling `Date()` without `new`
ar-tama Aug 6, 2026
fa002a8
fix(core): keep `Date()` callable without `new`
ar-tama Aug 6, 2026
4c7cd3c
chore: update changeset to match the final `Reflect.construct` implem…
ar-tama Aug 7, 2026
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5 changes: 5 additions & 0 deletions .changeset/date-subclass-vm.md
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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.
58 changes: 58 additions & 0 deletions packages/core/src/vm/index.test.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
expect(result).toEqual(specificTime);
});

it('should support subclassing `Date`', () => {
const { context } = createContext({ seed, fixedTimestamp });

const result = vm.runInContext(
`
class Sub extends Date {
constructor(...args) {
super(...args);
this.tag = 'sub';
}
label() {
return 'sub';
}
}
const sub = new Sub(2026, 6, 29);
const defaulted = new Sub();
({
isSub: sub instanceof Sub,
isDate: sub instanceof Date,
keepsMethods: sub.label(),
keepsFields: sub.tag,
argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
defaultedIsFixed: defaulted.getTime(),
})
`,
context
);

expect(result.isSub).toBe(true);
expect(result.isDate).toBe(true);
expect(result.keepsMethods).toBe('sub');
expect(result.keepsFields).toBe('sub');
expect(result.argsForwarded).toBe(true);
expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
});

it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
const { context } = createContext({ seed, fixedTimestamp });

const result = vm.runInContext('Date()', context);

expect(result).toBeTypeOf('string');
expect(result).toEqual(vm.runInContext('new Date().toString()', context));
// Per spec, `Date()` as a function ignores its arguments
expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
});

it('should preserve `Date` static methods', () => {
const { context } = createContext({ seed, fixedTimestamp });

expect(
vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
).toEqual(946684800000);
expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
946684800000
);
});

it('should have deterministic `crypto.getRandomValues()`', () => {
const { context } = createContext({ seed, fixedTimestamp });

Expand Down
21 changes: 13 additions & 8 deletions packages/core/src/vm/index.ts
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
// Deterministic `Math.random()`
g.Math.random = rng;

// Override `Date` constructor to return fixed time when called without arguments
// Override `Date` constructor to return fixed time when called without
// arguments. Constructing through `Reflect.construct` with `new.target`
// keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
// plain function (rather than a `class`) keeps `Date()` callable without
// `new`, which per spec ignores its arguments and returns the time string.
const Date_ = g.Date;
// biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
(g as any).Date = function Date(
...args: Parameters<(typeof globalThis)['Date']>[]
) {
if (args.length === 0) {
return new Date_(fixedTimestamp);
(g as any).Date = function Date(...args: any[]) {
if (new.target === undefined) {
return new Date_(fixedTimestamp).toString();
}
// @ts-expect-error - Args is `Date` constructor arguments
return new Date_(...args);
return Reflect.construct(
Date_,
args.length === 0 ? [fixedTimestamp] : args,
new.target
);
};
(g as any).Date.prototype = Date_.prototype;
// Preserve static methods
Expand Down
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, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
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btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
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navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
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[ci] Run CI for #3372 (Date subclassing fix)#3419

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[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
Skip to content
[ci] Run CI for #3372 (Date subclassing fix)#3419

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 Closed

TooTallNate
wants to merge
5
commits into

from


+76

−8

 Closed


[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
Skip to content
[ci] Run CI for #3372 (Date subclassing fix)#3419

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 Closed

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wants to merge
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commits into

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+76

−8

 Closed


[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
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[ci] Run CI for #3372 (Date subclassing fix)#3419

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[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
Skip to content
[ci] Run CI for #3372 (Date subclassing fix)#3419

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−8

 Closed


[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
Skip to content
[ci] Run CI for #3372 (Date subclassing fix)#3419

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 Closed

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commits into

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+76

−8

 Closed


[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

Expand Down

21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
[ci] Run CI for #3372 (Date subclassing fix) by TooTallNate · Pull Request #3419 · vercel/workflow · GitHub
Skip to content
[ci] Run CI for #3372 (Date subclassing fix)#3419

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 Closed

TooTallNate
wants to merge
5
commits into

from


+76

−8

 Closed


[ci] Run CI for #3372 (Date subclassing fix)
#3419
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8283e83

test: add failing test for Date subclassing in workflow VM


ar-tama Aug 6, 2026
58bc5d0

fix(core): preserve `new.target` in the deterministic `Date` override…


ar-tama Aug 6, 2026
4601046

test: add failing test for calling `Date()` without `new`


ar-tama Aug 6, 2026
fa002a8

fix(core): keep `Date()` callable without `new`


ar-tama Aug 6, 2026
4c7cd3c

chore: update changeset to match the final `Reflect.construct` implem…


ar-tama Aug 7, 2026

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5 changes: 5 additions & 0 deletions
.changeset/date-subclass-vm.md

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,5 @@
---
'@workflow/core': patch
---

Fix `Date` subclassing inside workflow functions. The deterministic `Date` override in the workflow VM now forwards `new.target` via `Reflect.construct`, so subclasses like `TZDate` from `@date-fns/tz` keep their identity, methods, and fields. Calling `Date()` without `new` now returns the (fixed) time string per spec, instead of a `Date` object.

58 changes: 58 additions & 0 deletions
packages/core/src/vm/index.test.ts

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Expand Up@@ -49,6 +49,64 @@ describe('createContext', () => {
 expect(result).toEqual(specificTime);
 });

 it('should support subclassing `Date`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext(
 `
 class Sub extends Date {
 constructor(...args) {
 super(...args);
 this.tag = 'sub';
 }
 label() {
 return 'sub';
 }
 }
 const sub = new Sub(2026, 6, 29);
 const defaulted = new Sub();
 ({
 isSub: sub instanceof Sub,
 isDate: sub instanceof Date,
 keepsMethods: sub.label(),
 keepsFields: sub.tag,
 argsForwarded: sub.getTime() === new Date(2026, 6, 29).getTime(),
 defaultedIsFixed: defaulted.getTime(),
 })
 `,
 context
 );

 expect(result.isSub).toBe(true);
 expect(result.isDate).toBe(true);
 expect(result.keepsMethods).toBe('sub');
 expect(result.keepsFields).toBe('sub');
 expect(result.argsForwarded).toBe(true);
 expect(result.defaultedIsFixed).toEqual(fixedTimestamp);
 });

 it('should keep `Date()` callable without `new`, returning the fixed time string', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 const result = vm.runInContext('Date()', context);

 expect(result).toBeTypeOf('string');
 expect(result).toEqual(vm.runInContext('new Date().toString()', context));
 // Per spec, `Date()` as a function ignores its arguments
 expect(vm.runInContext('Date(2000, 0, 1)', context)).toEqual(result);
 });

 it('should preserve `Date` static methods', () => {
 const { context } = createContext({ seed, fixedTimestamp });

 expect(
 vm.runInContext("Date.parse('2000-01-01T00:00:00.000Z')", context)
 ).toEqual(946684800000);
 expect(vm.runInContext('Date.UTC(2000, 0, 1)', context)).toEqual(
 946684800000
 );
 });

 it('should have deterministic `crypto.getRandomValues()`', () => {
 const { context } = createContext({ seed, fixedTimestamp });

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21 changes: 13 additions & 8 deletions
packages/core/src/vm/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -60,17 +60,22 @@ export function createContext(options: CreateContextOptions) {
 // Deterministic `Math.random()`
 g.Math.random = rng;

 // Override `Date` constructor to return fixed time when called without arguments
 // Override `Date` constructor to return fixed time when called without
 // arguments. Constructing through `Reflect.construct` with `new.target`
 // keeps subclassing intact (e.g. `TZDate` from `@date-fns/tz`), while a
 // plain function (rather than a `class`) keeps `Date()` callable without
 // `new`, which per spec ignores its arguments and returns the time string.
 const Date_ = g.Date;
 // biome-ignore lint/suspicious/noShadowRestrictedNames: We're shadowing the global `Date` property to make it deterministic.
 (g as any).Date = function Date(
 ...args: Parameters<(typeof globalThis)['Date']>[]
 ) {
 if (args.length === 0) {
 return new Date_(fixedTimestamp);
 (g as any).Date = function Date(...args: any[]) {
 if (new.target === undefined) {
 return new Date_(fixedTimestamp).toString();
 }
 // @ts-expect-error - Args is `Date` constructor arguments
 return new Date_(...args);
 return Reflect.construct(
 Date_,
 args.length === 0 ? [fixedTimestamp] : args,
 new.target
 );
 };
 (g as any).Date.prototype = Date_.prototype;
 // Preserve static methods
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