From fe707f88a47e80a52e1ba54a1c8ae873061c6a62 Mon Sep 17 00:00:00 2001
From: syuilo <syuilotan@yahoo.co.jp>
Date: Sat, 1 Dec 2018 10:40:09 +0900
Subject: [PATCH] [MFM] Better MFM parsing

---
 src/mfm/parse.ts  | 41 -----------------------------------------
 src/mfm/parser.ts |  2 +-
 test/mfm.ts       | 29 ++++++++++++++++++++++++-----
 3 files changed, 25 insertions(+), 47 deletions(-)

diff --git a/src/mfm/parse.ts b/src/mfm/parse.ts
index ee434d8dd..01c8cc7d7 100644
--- a/src/mfm/parse.ts
+++ b/src/mfm/parse.ts
@@ -26,45 +26,6 @@ export default (source: string): Node[] => {
 	nodes = concatText(nodes);
 	concatTextRecursive(nodes);
 
-	function getBeforeTextNode(node: Node): Node {
-		if (node == null) return null;
-		if (node.name == 'text') return node;
-		if (node.children) return getBeforeTextNode(node.children[node.children.length - 1]);
-		return null;
-	}
-
-	function getAfterTextNode(node: Node): Node {
-		if (node == null) return null;
-		if (node.name == 'text') return node;
-		if (node.children) return getBeforeTextNode(node.children[0]);
-		return null;
-	}
-
-	function isBlockNode(node: Node): boolean {
-		return ['blockCode', 'center', 'quote', 'title'].includes(node.name);
-	}
-
-	/**
-	 * ブロック要素の前後にある改行を削除します
-	 * (ブロック要素自体が改行の役割を果たすため、余計に改行されてしまう)
-	 * @param nodes
-	 */
-	const removeNeedlessLineBreaks = (nodes: Node[]) => {
-		nodes.forEach((node, i) => {
-			if (node.children) removeNeedlessLineBreaks(node.children);
-			if (isBlockNode(node)) {
-				const before = getBeforeTextNode(nodes[i - 1]);
-				const after = getAfterTextNode(nodes[i + 1]);
-				if (before && before.props.text.endsWith('\n')) {
-					before.props.text = before.props.text.substring(0, before.props.text.length - 1);
-				}
-				if (after && after.props.text.startsWith('\n')) {
-					after.props.text = after.props.text.substring(1);
-				}
-			}
-		});
-	};
-
 	const removeEmptyTextNodes = (nodes: Node[]) => {
 		nodes.forEach(n => {
 			if (n.children) {
@@ -74,8 +35,6 @@ export default (source: string): Node[] => {
 		return nodes.filter(n => !(n.name == 'text' && n.props.text == ''));
 	};
 
-	removeNeedlessLineBreaks(nodes);
-
 	nodes = removeEmptyTextNodes(nodes);
 
 	return nodes;
diff --git a/src/mfm/parser.ts b/src/mfm/parser.ts
index 9e47baf89..467097d4f 100644
--- a/src/mfm/parser.ts
+++ b/src/mfm/parser.ts
@@ -254,7 +254,7 @@ const mfm = P.createLanguage({
 			const qInner = quote.join('\n').replace(/^>/gm, '').replace(/^ /gm, '');
 			if (qInner == '') return P.makeFailure(i, 'not a quote');
 			const contents = r.root.tryParse(qInner);
-			return P.makeSuccess(i + quote.join('\n').length, makeNodeWithChildren('quote', contents));
+			return P.makeSuccess(i + quote.join('\n').length + 1, makeNodeWithChildren('quote', contents));
 		})),
 	//#endregion
 
diff --git a/test/mfm.ts b/test/mfm.ts
index c89152f8a..bfbf595f1 100644
--- a/test/mfm.ts
+++ b/test/mfm.ts
@@ -299,6 +299,7 @@ describe('Text', () => {
 					nodeWithChildren('quote', [
 						text('foo')
 					]),
+					text('\n'),
 					nodeWithChildren('quote', [
 						text('bar')
 					]),
@@ -358,7 +359,7 @@ describe('Text', () => {
 			it('with before and after texts', () => {
 				const tokens = analyze('before\n> foo\nafter');
 				assert.deepEqual([
-					text('before'),
+					text('before\n'),
 					nodeWithChildren('quote', [
 						text('foo')
 					]),
@@ -366,6 +367,24 @@ describe('Text', () => {
 				], tokens);
 			});
 
+			it('multiple quotes', () => {
+				const tokens = analyze('> foo\nbar\n\n> foo\nbar\n\n> foo\nbar');
+				assert.deepEqual([
+					nodeWithChildren('quote', [
+						text('foo')
+					]),
+					text('bar\n\n'),
+					nodeWithChildren('quote', [
+						text('foo')
+					]),
+					text('bar\n\n'),
+					nodeWithChildren('quote', [
+						text('foo')
+					]),
+					text('bar'),
+				], tokens);
+			});
+
 			it('require line break before ">"', () => {
 				const tokens = analyze('foo>bar');
 				assert.deepEqual([
@@ -388,11 +407,11 @@ describe('Text', () => {
 			it('trim line breaks', () => {
 				const tokens = analyze('foo\n\n>a\n>>b\n>>\n>>>\n>>>c\n>>>\n>d\n\n');
 				assert.deepEqual([
-					text('foo\n'),
+					text('foo\n\n'),
 					nodeWithChildren('quote', [
-						text('a'),
+						text('a\n'),
 						nodeWithChildren('quote', [
-							text('b\n'),
+							text('b\n\n'),
 							nodeWithChildren('quote', [
 								text('\nc\n')
 							])
@@ -664,7 +683,7 @@ describe('Text', () => {
 			it('with before and after texts', () => {
 				const tokens = analyze('before\n【foo】\nafter');
 				assert.deepEqual([
-					text('before'),
+					text('before\n'),
 					nodeWithChildren('title', [
 						text('foo')
 					]),