mirror of https://github.com/sveltejs/svelte
49 lines
750 B
49 lines
750 B
const subscribers = [];
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let value = 'initial';
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const observable = {
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subscribe: fn => {
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subscribers.push(fn);
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fn(value);
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return {
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unsubscribe: () => {
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const i = subscribers.indexOf(fn);
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subscribers.splice(i, 1);
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}
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};
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}
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};
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export default {
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props: {
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observable,
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visible: false
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},
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html: ``,
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async test({ assert, component, target }) {
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assert.equal(subscribers.length, 0);
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component.visible = true;
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assert.equal(subscribers.length, 1);
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assert.htmlEqual(target.innerHTML, `
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<p>value: initial</p>
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`);
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value = 42;
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await subscribers.forEach(fn => fn(value));
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assert.htmlEqual(target.innerHTML, `
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<p>value: 42</p>
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`);
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component.visible = false;
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assert.equal(subscribers.length, 0);
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}
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}; |