import assert from 'node:assert/strict';
import diagnosticsChannel from 'node:diagnostics_channel';
import { describe, it } from 'node:test';
import type { TransformStageEvent } from '../dist/transform-types.js';
import {
endTransformStage,
type StageBudget,
startTransformStage,
} from '../dist/transform.js';
describe('transform telemetry', () => {
it('redacts query and fragment from the URL', () => {
const channel = diagnosticsChannel.channel('superfetch.transform');
const events: TransformStageEvent[] = [];
const subscriber = (event: unknown) => {
events.push(event as TransformStageEvent);
};
channel.subscribe(subscriber);
try {
const ctx = startTransformStage('https://example.com/path?x=1#y', 'test');
endTransformStage(ctx);
} finally {
channel.unsubscribe(subscriber);
}
assert.equal(events.length, 1);
assert.equal(events[0]?.url, 'https://example.com/path');
});
it('startTransformStage accepts budget and tracks remaining budget', () => {
const channel = diagnosticsChannel.channel('superfetch.transform');
const events: TransformStageEvent[] = [];
const subscriber = (event: unknown) => {
events.push(event as TransformStageEvent);
};
const budget: StageBudget = { totalBudgetMs: 1000, elapsedMs: 200 };
channel.subscribe(subscriber);
try {
const ctx = startTransformStage('https://example.com', 'test', budget);
assert.ok(ctx, 'context should be created');
assert.equal(ctx.budgetMs, 800, 'remaining budget should be 800ms');
assert.equal(ctx.totalBudgetMs, 1000, 'total budget should be preserved');
endTransformStage(ctx);
} finally {
channel.unsubscribe(subscriber);
}
assert.equal(events.length, 1);
});
it('endTransformStage returns duration in milliseconds', () => {
const channel = diagnosticsChannel.channel('superfetch.transform');
const subscriber = () => {};
channel.subscribe(subscriber);
try {
const ctx = startTransformStage('https://example.com', 'test');
const duration = endTransformStage(ctx);
assert.equal(typeof duration, 'number');
assert.ok(duration >= 0, 'duration should be non-negative');
} finally {
channel.unsubscribe(subscriber);
}
});
});
