yaml-unist-parser/dist/transforms/flow-seq.mjs

A YAML parser that produces output compatible with unist

import { createPosition } from "../factories/position.mjs";
import { maybeContentPropertyToken, tokens } from "../cst.mjs";
import { extractComments } from "../utils/extract-comments.mjs";
import { createFlowMappingItem } from "../factories/flow-mapping-item.mjs";
import { transformPair } from "./pair.mjs";
import { createFlowSequence } from "../factories/flow-sequence.mjs";
import { createFlowSequenceItem } from "../factories/flow-sequence-item.mjs";
import { getLast } from "../utils/get-last.mjs";
import * as YAML from "yaml";

//#region src/transforms/flow-seq.ts
function transformFlowSeq(flowSeq, context, props) {
	const srcToken = flowSeq.srcToken;
	// istanbul ignore if -- @preserve
	if (!srcToken || srcToken.type !== "flow-collection") throw new Error("Expected flow-collection CST node for flow sequence");
	const flowSequenceItems = flowSeq.items.map((item, index) => {
		const srcItem = srcToken.items[index];
		if (isBlockMappingOfImmediateChildOfFlowSequence(item, srcItem)) return transformPair(getLast(item.items), srcItem, context, createFlowMappingItem);
		if (!YAML.isPair(item)) {
			const propTokens = [];
			for (const token of tokens(srcItem.start)) {
				if (maybeContentPropertyToken(token)) {
					propTokens.push(token);
					continue;
				}
				// istanbul ignore else -- @preserve
				if (token.type === "comma") continue;
				// istanbul ignore next -- @preserve
				throw new Error(`Unexpected token type in sequence item start: ${token.type}`);
			}
			const node = context.transformNode(item, { tokens: propTokens });
			return createFlowSequenceItem(createPosition(node.position.start, node.position.end), node);
		} else return transformPair(item, srcItem, context, createFlowMappingItem);
	});
	if (flowSeq.items.length < srcToken.items.length) for (let i = flowSeq.items.length; i < srcToken.items.length; i++) {
		const srcItem = srcToken.items[i];
		for (const token of extractComments(srcItem.start, context)) {
			// istanbul ignore else -- @preserve
			if (token.type === "comma") continue;
			// istanbul ignore next -- @preserve
			throw new Error(`Unexpected token type in collection item start: ${token.type}`);
		}
	}
	let flowSeqEndToken = null;
	for (const token of tokens(srcToken.end)) {
		if (token.type === "comment") {
			context.transformComment(token);
			continue;
		}
		// istanbul ignore else -- @preserve
		if (token.type === "flow-seq-end") {
			flowSeqEndToken = token;
			continue;
		}
		// istanbul ignore next -- @preserve
		throw new Error(`Unexpected token type in flow seq end: ${token.type}`);
	}
	// istanbul ignore if -- @preserve
	if (!flowSeqEndToken) throw new Error("Expected flow-seq-end token");
	return createFlowSequence(context.transformRange([srcToken.start.offset, flowSeqEndToken.offset + flowSeqEndToken.source.length]), context.transformContentProperties(flowSeq, props.tokens), flowSequenceItems);
}
/**
* Checks whether the given item is a block mapping that is an immediate child of a flow sequence.
* This is determined by checking if the item does not have a source token and contains exactly one item.
*
* e.g.
*
* ```yaml
* [ key: value ]
* ```
*/
function isBlockMappingOfImmediateChildOfFlowSequence(item, srcItem) {
	if (item.srcToken) return false;
	// istanbul ignore if -- @preserve
	if (!YAML.isMap(item)) return false;
	// istanbul ignore if -- @preserve
	if (item.items.length !== 1) return false;
	return item.items[0].srcToken === srcItem;
}

//#endregion
export { transformFlowSeq };