28 lines
823 B
TypeScript
28 lines
823 B
TypeScript
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// @strict: true
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// Repro from #23977
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export function assertIsElement(node: Node | null): node is Element {
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let nodeType = node === null ? null : node.nodeType;
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return nodeType === 1;
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}
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export function assertNodeTagName<
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T extends keyof ElementTagNameMap,
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U extends ElementTagNameMap[T]>(node: Node | null, tagName: T): node is U {
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if (assertIsElement(node)) {
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const nodeTagName = node.tagName.toLowerCase();
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return nodeTagName === tagName;
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}
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return false;
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}
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export function assertNodeProperty<
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T extends keyof ElementTagNameMap,
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P extends keyof ElementTagNameMap[T],
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V extends HTMLElementTagNameMap[T][P]>(node: Node | null, tagName: T, prop: P, value: V) {
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if (assertNodeTagName(node, tagName)) {
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node[prop];
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}
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}
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