Fix cursor jumping

README.md

@@ -96,8 +96,9 @@ Blacklist mode is the opposite of whitelist mode - it **only removes** links tha
 - **2.1.1**: Added hyperlink whitelist feature to preserve specified domains/URLs.
 - **2.2.0**: Added hyperlink type filtering (internal/external/both) and hyperlink/wikilink whitelist feature.
 - **2.3.0**: Added explicit commands to remove links from either internal or extrnal origin.
-- **2.4.0**: Added blacklist mode to explicitly remove only links you want (opposite of whitelist).
+- **2.4.0**: Added sblacklist mode to explicitly remove only links you want (opposite of whitelist).
 - **2.4.2**: Upgrade all dependencies to latest versions and fix all issues reported in community page.
 - **2.5.0**: Added support for stripping AI and Wikipedia citation links.
 - **2.5.1**: Fix issues reported in community page.
-- **3.0.0**: Added support for filtering out what types of embeds to remove (image, audio, video, pdf, etc).
+- **3.0.0**: Added support for filtering out what types of embeds to remove (image, audio, video, pdf, etc).
+- **3.1.0**: Fix cursor position jumping when using the remove link command.

editorUtils.test.ts

@@ -0,0 +1,206 @@
+import { describe, expect, test } from "@jest/globals";
+import type { Editor, EditorPosition } from "obsidian";
+
+import { applyTextUpdate, diffRange } from "./editorUtils";
+
+/**
+ * Minimal Obsidian Editor, covering only the methods
+ * applyTextUpdate touches. Records the calls the tests assert on.
+ */
+class StubEditor {
+	value: string;
+	anchor: EditorPosition;
+	head: EditorPosition;
+	scroll = { top: 420, left: 7 };
+	replacedRanges: {
+		insert: string;
+		from: EditorPosition;
+		to: EditorPosition;
+	}[] = [];
+	scrolledTo: { left: number; top: number }[] = [];
+	setValueCalls = 0;
+
+	constructor(value: string, cursor: EditorPosition = { line: 0, ch: 0 }) {
+		this.value = value;
+		this.anchor = cursor;
+		this.head = cursor;
+	}
+
+	getValue(): string {
+		return this.value;
+	}
+
+	setValue(value: string): void {
+		this.setValueCalls++;
+		this.value = value;
+	}
+
+	getLine(line: number): string {
+		return this.value.split("\n")[line] ?? "";
+	}
+
+	lastLine(): number {
+		return this.value.split("\n").length - 1;
+	}
+
+	getCursor(mode: "anchor" | "head"): EditorPosition {
+		return mode === "anchor" ? this.anchor : this.head;
+	}
+
+	setSelection(anchor: EditorPosition, head: EditorPosition): void {
+		this.anchor = anchor;
+		this.head = head;
+	}
+
+	getScrollInfo(): { top: number; left: number } {
+		return this.scroll;
+	}
+
+	scrollTo(left: number, top: number): void {
+		this.scrolledTo.push({ left, top });
+	}
+
+	offsetToPos(offset: number): EditorPosition {
+		const lines = this.value.slice(0, offset).split("\n");
+		return {
+			line: lines.length - 1,
+			ch: (lines[lines.length - 1] ?? "").length,
+		};
+	}
+
+	posToOffset(pos: EditorPosition): number {
+		const lines = this.value.split("\n");
+		let offset = 0;
+		for (let i = 0; i < pos.line; i++) {
+			offset += (lines[i] ?? "").length + 1;
+		}
+		return offset + pos.ch;
+	}
+
+	replaceRange(
+		insert: string,
+		from: EditorPosition,
+		to: EditorPosition,
+	): void {
+		this.replacedRanges.push({ insert, from, to });
+		this.value =
+			this.value.slice(0, this.posToOffset(from)) +
+			insert +
+			this.value.slice(this.posToOffset(to));
+	}
+
+	asEditor(): Editor {
+		return this as unknown as Editor;
+	}
+}
+
+describe("diffRange", () => {
+	test("identical text produces no change", () => {
+		expect(diffRange("same text", "same text")).toBeNull();
+	});
+
+	test("change at the start", () => {
+		expect(diffRange("[a](http://a) tail", "a tail")).toEqual({
+			from: 0,
+			to: 13,
+			insert: "a",
+		});
+	});
+
+	test("change in the middle", () => {
+		expect(diffRange("head [a](http://a) tail", "head a tail")).toEqual({
+			from: 5,
+			to: 18,
+			insert: "a",
+		});
+	});
+
+	test("change at the end", () => {
+		expect(diffRange("head [a](http://a)", "head a")).toEqual({
+			from: 5,
+			to: 18,
+			insert: "a",
+		});
+	});
+
+	test("pure deletion leaves an empty insert", () => {
+		expect(diffRange("keep [[gone]] keep", "keep  keep")).toEqual({
+			from: 5,
+			to: 13,
+			insert: "",
+		});
+	});
+
+	test("everything removed", () => {
+		expect(diffRange("[[gone]]", "")).toEqual({
+			from: 0,
+			to: 8,
+			insert: "",
+		});
+	});
+
+	test("prefix and suffix do not overlap on repeated text", () => {
+		const diff = diffRange("aaaa", "aa");
+		expect(diff).not.toBeNull();
+		const { from, to, insert } = diff!;
+		expect(from).toBeLessThanOrEqual(to);
+		expect("aaaa".slice(0, from) + insert + "aaaa".slice(to)).toBe("aa");
+	});
+});
+
+describe("applyTextUpdate", () => {
+	test("returns false and touches nothing when content is unchanged", () => {
+		const editor = new StubEditor("no links here");
+
+		expect(applyTextUpdate(editor.asEditor(), "no links here")).toBe(false);
+		expect(editor.replacedRanges).toHaveLength(0);
+		expect(editor.scrolledTo).toHaveLength(0);
+		expect(editor.setValueCalls).toBe(0);
+	});
+
+	test("replaces only the changed span and never calls setValue", () => {
+		const editor = new StubEditor(
+			"line one\nline [two](http://two)\nline three",
+		);
+
+		expect(
+			applyTextUpdate(
+				editor.asEditor(),
+				"line one\nline two\nline three",
+			),
+		).toBe(true);
+		expect(editor.value).toBe("line one\nline two\nline three");
+		expect(editor.setValueCalls).toBe(0);
+		expect(editor.replacedRanges).toEqual([
+			{
+				insert: "two",
+				from: { line: 1, ch: 5 },
+				to: { line: 1, ch: 22 },
+			},
+		]);
+	});
+
+	test("restores the cursor and the scroll position", () => {
+		const editor = new StubEditor(
+			"line one\nline [two](http://two)\nline three",
+			{ line: 2, ch: 4 },
+		);
+
+		applyTextUpdate(editor.asEditor(), "line one\nline two\nline three");
+
+		expect(editor.head).toEqual({ line: 2, ch: 4 });
+		expect(editor.anchor).toEqual({ line: 2, ch: 4 });
+		expect(editor.scrolledTo).toEqual([{ left: 7, top: 420 }]);
+	});
+
+	test("clamps a cursor that the edit pushed past the end of its line", () => {
+		const editor = new StubEditor("line [two](http://two)", {
+			line: 0,
+			ch: 22,
+		});
+
+		applyTextUpdate(editor.asEditor(), "line two");
+
+		expect(editor.head).toEqual({ line: 0, ch: 8 });
+	});
+});

editorUtils.ts

@@ -0,0 +1,78 @@
+import type { Editor, EditorPosition } from "obsidian";
+
+export interface TextDiff {
+	from: number;
+	to: number;
+	insert: string;
+}
+
+/**
+ * Narrow a whole-document rewrite down to the single span that actually changed,
+ * so the editor can map the cursor and scroll position through the edit instead
+ * of collapsing them to the start of the document.
+ */
+export function diffRange(oldText: string, newText: string): TextDiff | null {
+	if (oldText === newText) {
+		return null;
+	}
+
+	let prefix = 0;
+	const maxPrefix = Math.min(oldText.length, newText.length);
+	while (prefix < maxPrefix && oldText[prefix] === newText[prefix]) {
+		prefix++;
+	}
+
+	let suffix = 0;
+	const maxSuffix = maxPrefix - prefix;
+	while (
+		suffix < maxSuffix &&
+		oldText[oldText.length - 1 - suffix] ===
+			newText[newText.length - 1 - suffix]
+	) {
+		suffix++;
+	}
+
+	return {
+		from: prefix,
+		to: oldText.length - suffix,
+		insert: newText.slice(prefix, newText.length - suffix),
+	};
+}
+
+function clampPosition(
+	editor: Editor,
+	position: EditorPosition,
+): EditorPosition {
+	const line = Math.min(Math.max(position.line, 0), editor.lastLine());
+	const ch = Math.min(Math.max(position.ch, 0), editor.getLine(line).length);
+	return { line, ch };
+}
+
+/**
+ * Replace the editor's content, keeping the cursor and viewport in place.
+ * Returns false when the new content is identical to the current content.
+ */
+export function applyTextUpdate(editor: Editor, newContent: string): boolean {
+	const diff = diffRange(editor.getValue(), newContent);
+	if (!diff) {
+		return false;
+	}
+
+	const anchor = editor.getCursor("anchor");
+	const head = editor.getCursor("head");
+	const scroll = editor.getScrollInfo();
+
+	editor.replaceRange(
+		diff.insert,
+		editor.offsetToPos(diff.from),
+		editor.offsetToPos(diff.to),
+	);
+
+	editor.setSelection(
+		clampPosition(editor, anchor),
+		clampPosition(editor, head),
+	);
+	editor.scrollTo(scroll.left, scroll.top);
+
+	return true;
+}

main.ts

@@ -1,4 +1,5 @@
 import { App, Editor, Notice, Plugin, PluginSettingTab, Setting } from 'obsidian';
+import { applyTextUpdate } from './editorUtils';
 import { EmbedTypeOptions, removeCitations, removeHyperlinks, removeWikilinks, removeWikipediaCitations } from './removeLinks';
 
 interface HyperlinkRemoverSettings {
@@ -70,10 +71,8 @@ export default class HyperlinkRemover extends Plugin {
 			id: 'remove-links-from-file',
 			name: 'Remove links from file',
 			editorCallback: (editor: Editor) => {
-				const content = editor.getValue();
-				const updatedContent = this.processText(content);
-				if (content !== updatedContent) {
-					editor.setValue(updatedContent);
+				const updatedContent = this.processText(editor.getValue());
+				if (applyTextUpdate(editor, updatedContent)) {
 					new Notice('Links removed from file');
 				} else {
 					new Notice('No links found in the file');
@@ -85,10 +84,8 @@ export default class HyperlinkRemover extends Plugin {
 			id: 'remove-external-links-from-file',
 			name: 'Remove external links from file',
 			editorCallback: (editor: Editor) => {
-				const content = editor.getValue();
-				const updatedContent = this.processText(content, 'external');
-				if (content !== updatedContent) {
-					editor.setValue(updatedContent);
+				const updatedContent = this.processText(editor.getValue(), 'external');
+				if (applyTextUpdate(editor, updatedContent)) {
 					new Notice('External links removed from file');
 				} else {
 					new Notice('No external links found in the file');
@@ -100,10 +97,8 @@ export default class HyperlinkRemover extends Plugin {
 			id: 'remove-internal-links-from-file',
 			name: 'Remove internal links from file',
 			editorCallback: (editor: Editor) => {
-				const content = editor.getValue();
-				const updatedContent = this.processText(content, 'internal');
-				if (content !== updatedContent) {
-					editor.setValue(updatedContent);
+				const updatedContent = this.processText(editor.getValue(), 'internal');
+				if (applyTextUpdate(editor, updatedContent)) {
 					new Notice('Internal links removed from file');
 				} else {
 					new Notice('No internal links found in the file');
@@ -134,10 +129,8 @@ export default class HyperlinkRemover extends Plugin {
 			id: 'remove-blacklisted-links-from-file',
 			name: 'Remove blacklisted links from file',
 			editorCallback: (editor: Editor) => {
-				const content = editor.getValue();
-				const updatedContent = this.processText(content, undefined, true);
-				if (content !== updatedContent) {
-					editor.setValue(updatedContent);
+				const updatedContent = this.processText(editor.getValue(), undefined, true);
+				if (applyTextUpdate(editor, updatedContent)) {
 					new Notice('Blacklisted links removed from file');
 				} else {
 					new Notice('No blacklisted links found in the file');
@@ -171,10 +164,8 @@ export default class HyperlinkRemover extends Plugin {
 					item.setTitle("Remove links from file")
 						.setIcon("unlink")
 						.onClick(() => {
-							const content = editor.getValue();
-							const updatedContent = this.processText(content);
-							if (content !== updatedContent) {
-								editor.setValue(updatedContent);
+							const updatedContent = this.processText(editor.getValue());
+							if (applyTextUpdate(editor, updatedContent)) {
 								new Notice('Links removed from file');
 							} else {
 								new Notice('No links found in the file');

manifest.json

@@ -1,7 +1,7 @@
 {
 	"id": "hyperlink-remover",
 	"name": "Link Remover",
-	"version": "3.0.0",
+	"version": "3.1.0",
 	"minAppVersion": "0.16.2",
 	"description": "Easily remove hyperlinks and wikilinks from selected text or the entire note.",
 	"author": "Daniel Agafonov",

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "link-remover",
-	"version": "3.0.0",
+	"version": "3.1.0",
 	"description": "Easily remove hyperlinks and wikilinks from selected text or the entire note",
 	"main": "main.js",
 	"scripts": {

versions.json

@@ -16,5 +16,6 @@
 	"2.4.2": "0.16.2",
 	"2.5.0": "0.16.2",
 	"2.5.1": "0.16.2",
-	"3.0.0": "0.16.2"
+	"3.0.0": "0.16.2",
+	"3.1.0": "0.16.2"
 }