From 539e3f1b6a664eb57ada2b187dd4753aeed5d6be Mon Sep 17 00:00:00 2001
From: Elian Doran <contact@eliandoran.me>
Date: Fri, 11 Apr 2025 19:25:22 +0300
Subject: [PATCH] feat(export/markdown: trim confusing whitespace in lists

---
 src/services/export/markdown.spec.ts | 26 ++++++++++++++++++++++++++
 src/services/export/markdown.ts      | 22 ++++++++++++++++++++++
 src/services/import/markdown.spec.ts | 18 ++++++++++++++++++
 3 files changed, 66 insertions(+)

diff --git a/src/services/export/markdown.spec.ts b/src/services/export/markdown.spec.ts
index 74c6a9600..a344d975f 100644
--- a/src/services/export/markdown.spec.ts
+++ b/src/services/export/markdown.spec.ts
@@ -289,4 +289,30 @@ describe("Markdown export", () => {
         expect(markdownExportService.toMarkdown(html)).toBe(expected);
     });
 
+    it("does not generate additional spacing when exporting lists with paragraph", () => {
+        const html = trimIndentation`\
+            <ul>
+                <li><a href="https://github.com/JYC333">@JYC333</a> made their first contribution
+                            in <a href="https://github.com/TriliumNext/Notes/pull/294">#294</a>
+
+                </li>
+                <li>
+                <p><a href="https://github.com/TriliumNext/Notes/issues/375">Note Tooltip isn't removed when clicking on internal trilium link in read-only mode</a>
+
+                </p>
+                </li>
+                <li>
+                <p><a href="https://github.com/TriliumNext/Notes/issues/384">Calendar dropdown won't close if click/right-click other button that open notes from launcher bar</a>
+
+                </p>
+                </li>
+            </ul>
+        `;
+        const expected = trimIndentation`\
+            *   [@JYC333](https://github.com/JYC333) made their first contribution in [#294](https://github.com/TriliumNext/Notes/pull/294)
+            *   [Note Tooltip isn't removed when clicking on internal trilium link in read-only mode](https://github.com/TriliumNext/Notes/issues/375)
+            *   [Calendar dropdown won't close if click/right-click other button that open notes from launcher bar](https://github.com/TriliumNext/Notes/issues/384)`;
+        expect(markdownExportService.toMarkdown(html)).toBe(expected);
+    });
+
 });
diff --git a/src/services/export/markdown.ts b/src/services/export/markdown.ts
index e524a6274..c4c71eee2 100644
--- a/src/services/export/markdown.ts
+++ b/src/services/export/markdown.ts
@@ -46,6 +46,7 @@ function toMarkdown(content: string) {
         instance.addRule("inlineLink", buildInlineLinkFilter());
         instance.addRule("figure", buildFigureFilter());
         instance.addRule("math", buildMathFilter());
+        instance.addRule("li-1", buildListItemFilter());
         instance.use(gfm);
         instance.keep([ "kbd" ]);
     }
@@ -207,6 +208,27 @@ function buildFigureFilter(): Rule {
     }
 }
 
+// Keep in line with https://github.com/mixmark-io/turndown/blob/master/src/commonmark-rules.js.
+function buildListItemFilter(): Rule {
+    return {
+        filter: "li",
+        replacement(content, node, options) {
+            content = content
+                .trim()
+                .replace(/\n/gm, '\n    ') // indent
+            let prefix = options.bulletListMarker + '   '
+            const parent = node.parentNode as HTMLElement;
+            if (parent.nodeName === 'OL') {
+                var start = parent.getAttribute('start')
+                var index = Array.prototype.indexOf.call(parent.children, node)
+                prefix = (start ? Number(start) + index : index + 1) + '.  '
+            }
+            const result = prefix + content + (node.nextSibling && !/\n$/.test(content) ? '\n' : '');
+            return result;
+        }
+    }
+}
+
 function buildMathFilter(): Rule {
     const MATH_INLINE_PREFIX = "\\(";
     const MATH_INLINE_SUFFIX = "\\)";
diff --git a/src/services/import/markdown.spec.ts b/src/services/import/markdown.spec.ts
index f1ca4971d..429e61b67 100644
--- a/src/services/import/markdown.spec.ts
+++ b/src/services/import/markdown.spec.ts
@@ -208,4 +208,22 @@ second line 2</code></pre><ul><li>Hello</li><li>world</li></ul><ol><li>Hello</li
         expect(markdownService.renderToHtml(input, "Title")).toStrictEqual(expected);
     });
 
+    it("does not generate additional spacing when importing lists", () => {
+        const input = trimIndentation`\
+            ### 🐞 Bugfixes
+
+            *   [v0.90.4 docker does not read USER\_UID and USER\_GID from environment](https://github.com/TriliumNext/Notes/issues/331)
+            *   [Invalid CSRF token on Android phone](https://github.com/TriliumNext/Notes/issues/318)
+            *   [Excess spacing in lists](https://github.com/TriliumNext/Notes/issues/341)`;
+        const expected = [
+            /*html*/`<h3>🐞 Bugfixes</h3>`,
+            /*html*/`<ul>`,
+            /*html*/`<li><a href="https://github.com/TriliumNext/Notes/issues/331">v0.90.4 docker does not read USER_UID and USER_GID from environment</a></li>`,
+            /*html*/`<li><a href="https://github.com/TriliumNext/Notes/issues/318">Invalid CSRF token on Android phone</a></li>`,
+            /*html*/`<li><a href="https://github.com/TriliumNext/Notes/issues/341">Excess spacing in lists</a></li>`,
+            /*html*/`</ul>`
+        ].join("");
+        expect(markdownService.renderToHtml(input, "Title")).toStrictEqual(expected);
+    });
+
 });