Improve test coverage (#1994)

* refactor type & logic

* re-define `PlainNodeParser` as `TerminateNodeParser`

* refactor type

* fix logic

* refactor

Author: progfay

lcov.info

@@ -2,7 +2,7 @@ import type { Row } from "./Row.ts";
 
 export interface CodeBlockPack {
 	type: "codeBlock";
-	rows: Row[];
+	rows: [Row, ...Row[]];
 }
 
 /**
@@ -17,9 +17,8 @@ export interface CodeBlock {
 
 export const convertToCodeBlock = (pack: CodeBlockPack): CodeBlock => {
 	const {
-		rows: [head, ...body],
+		rows: [{ indent, text }, ...body],
 	} = pack;
-	const { indent = 0, text = "" } = head ?? {};
 	const fileName: string = text.replace(/^\s*code:/, "");
 
 	return {

src/block/CodeBlock.ts

@@ -7,31 +7,35 @@ import type { TitlePack } from "./Title.ts";
 
 export type Pack = TitlePack | CodeBlockPack | TablePack | LinePack;
 
-const isChildRowOfPack = (pack: Pack, row: Row): boolean =>
-	(pack.type === "codeBlock" || pack.type === "table") &&
-	row.indent > (pack.rows[0]?.indent ?? 0);
+const isChildRowOfPack = (
+	{ type, rows: [firstRow] }: Pack,
+	row: Row,
+): boolean =>
+	(type === "codeBlock" || type === "table") && row.indent > firstRow.indent;
 
 const packing = (packs: Pack[], row: Row): Pack[] => {
 	const lastPack = packs[packs.length - 1];
 	if (lastPack !== undefined && isChildRowOfPack(lastPack, row)) {
 		lastPack.rows.push(row);
-		return packs;
+	} else {
+		packs.push({
+			type: /^\s*code:/.test(row.text)
+				? "codeBlock"
+				: /^\s*table:/.test(row.text)
+					? "table"
+					: "line",
+			rows: [row],
+		});
 	}
 
-	packs.push({
-		type: /^\s*code:/.test(row.text)
-			? "codeBlock"
-			: /^\s*table:/.test(row.text)
-				? "table"
-				: "line",
-		rows: [row],
-	});
-
 	return packs;
 };
 
-export const packRows = (rows: Row[], opts: ParserOption): Pack[] => {
-	if (opts.hasTitle ?? true) {
+export const packRows = (
+	rows: Row[],
+	{ hasTitle = true }: ParserOption,
+): Pack[] => {
+	if (hasTitle) {
 		const [title, ...body] = rows;
 		if (title === undefined) return [];
 		return [

src/block/Pack.ts

@@ -5,6 +5,6 @@ export interface Row {
 
 export const parseToRows = (input: string): Row[] =>
 	input.split("\n").map((text) => ({
-		indent: /^\s+/.exec(text)?.[0]?.length ?? 0,
+		indent: /^\s+/.exec(text)?.[0].length ?? 0,
 		text,
 	}));

src/block/Row.ts

@@ -4,7 +4,7 @@ import type { Row } from "./Row.ts";
 
 export interface TablePack {
 	type: "table";
-	rows: Row[];
+	rows: [Row, ...Row[]];
 }
 
 /**
@@ -19,9 +19,8 @@ export interface Table {
 
 export const convertToTable = (pack: TablePack): Table => {
 	const {
-		rows: [head, ...body],
+		rows: [{ indent, text }, ...body],
 	} = pack;
-	const { indent = 0, text = "" } = head ?? {};
 	const fileName = text.replace(/^\s*table:/, "");
 
 	return {

src/block/Table.ts

@@ -26,7 +26,7 @@ const createExternalLinkNode: NodeCreator<LinkNode | PlainNode> = (
 	const match = (
 		isHrefFirst ? /^https?:\/\/[^\s\]]+/ : /https?:\/\/[^\s\]]+$/
 	).exec(inner);
-	if (match?.[0] === undefined) return [];
+	if (match === null) return [];
 
 	const content = isHrefFirst
 		? inner.substring(match[0].length)

src/block/node/ExternalLinkNode.ts

@@ -1,6 +1,5 @@
 import type { NodeCreator } from "./creator.ts";
-import { createNodeParser } from "./creator.ts";
-import type { NodeParser } from "./index.ts";
+import type { TerminateNodeParser } from "./index.ts";
 import type { PlainNode } from "./type.ts";
 
 export const createPlainNode: NodeCreator<PlainNode> = (raw) => [
@@ -11,8 +10,4 @@ export const createPlainNode: NodeCreator<PlainNode> = (raw) => [
 	},
 ];
 
-export const PlainNodeParser: NodeParser = createNodeParser(createPlainNode, {
-	parseOnNested: true,
-	parseOnQuoted: true,
-	patterns: [/^()(.*)()$/],
-});
+export const PlainNodeParser: TerminateNodeParser = createPlainNode;

src/block/node/PlainNode.ts

@@ -7,34 +7,40 @@ export type NodeCreator<T extends Node> = (
 	opts: NodeParserOption,
 ) => T[];
 
+type NodeParserCreatorOptions = {
+	parseOnNested: boolean;
+	parseOnQuoted: boolean;
+	patterns: RegExp[];
+};
+
 type NodeParserCreator<T extends Node> = (
 	nodeCreator: NodeCreator<T>,
-	opts: { parseOnNested: boolean; parseOnQuoted: boolean; patterns: RegExp[] },
+	opts: NodeParserCreatorOptions,
 ) => NodeParser;
 
 export const createNodeParser: NodeParserCreator<Node> = (
 	nodeCreator,
 	{ parseOnNested, parseOnQuoted, patterns },
 ) => {
 	return (text, opts, next) => {
-		if (!parseOnNested && opts.nested) return next?.() ?? [];
-		if (!parseOnQuoted && opts.quoted) return next?.() ?? [];
+		if (!parseOnNested && opts.nested) return next();
+		if (!parseOnQuoted && opts.quoted) return next();
 
 		for (const pattern of patterns) {
 			const match = pattern.exec(text);
 			if (match === null) continue;
 
 			const left = text.substring(0, match.index);
-			const right = text.substring(match.index + (match[0]?.length ?? 0));
+			const right = text.substring(match.index + match[0].length);
 
-			const node = nodeCreator(match[0] ?? "", opts);
+			const node = nodeCreator(match[0], opts);
 			return [
 				...convertToNodes(left, opts),
 				...node,
 				...convertToNodes(right, opts),
 			];
 		}
 
-		return next?.() ?? [];
+		return next();
 	};
 };

src/block/node/creator.ts

@@ -28,13 +28,15 @@ export type NextNodeParser = () => Node[];
 export type NodeParser = (
 	text: string,
 	opts: NodeParserOption,
-	next?: NextNodeParser,
+	next: NextNodeParser,
+) => Node[];
+export type TerminateNodeParser = (
+	text: string,
+	opts: NodeParserOption,
 ) => Node[];
 
-const FalsyEliminator: NodeParser = (text, _, next) => {
-	if (text === "") return [];
-	return next?.() ?? [];
-};
+const FalsyEliminator: NodeParser = (text, _, next) =>
+	text !== "" ? next() : [];
 
 const combineNodeParsers =
 	(...parsers: NodeParser[]) =>

src/block/node/index.ts

@@ -24,9 +24,12 @@ export type Page = Block[];
  * @param opts parser options
  * @returns syntax tree of parsed input
  */
-export const parse = (input: string, opts?: ParserOption): Page => {
+export const parse = (
+	input: string,
+	{ hasTitle = true }: ParserOption = {},
+): Page => {
 	const rows = parseToRows(input);
-	const packs = packRows(rows, { hasTitle: opts?.hasTitle ?? true });
+	const packs = packRows(rows, { hasTitle });
 	return packs.map(convertToBlock);
 };
 
@@ -37,5 +40,5 @@ export const parse = (input: string, opts?: ParserOption): Page => {
  */
 export const getTitle = (input: string): string => {
 	const match = /^\s*\S.*$/m.exec(input);
-	return match?.[0]?.trim() ?? "Untitled";
+	return match?.[0].trim() ?? "Untitled";
 };