Communication: Fix cursor jump issue during list text editing

[asliayk]

Checklist

General

• I tested all changes and their related features with all corresponding user types on a test server.
• Language: I followed the guidelines for inclusive, diversity-sensitive, and appreciative language.
• I chose a title conforming to the naming conventions for pull requests.

Client

• I strictly followed the client coding and design guidelines.
• I added multiple integration tests (Jest) related to the features (with a high test coverage), while following the test guidelines.

Motivation and Context

When editing text in a list (unordered or ordered) within a message, the text cursor would previously jump to the end of the line after each character addition. (Closes #10133)

Description

The cursor now maintains its position during text modifications, allowing seamless editing. The fix involved introducing a return; condition to prevent unnecessary processing when no text is selected, and the cursor is within the current line.

Steps for Testing

Prerequisites:

• 1 User
• 1 Course with Communication enabled

1. Log in to Artemis
2. Navigate to Communication section of a course
3. Insert a list (unordered or ordered), write some text in the message input
4. Go to the middle of the text and start writing or deleting some characters
5. Verify correct cursor behavior

Testserver States

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Review Progress

Code Review

• Code Review 1
• Code Review 2

Manual Tests

• Test 1
• Test 2

Test Coverage

Client

Class/File	Line Coverage	Confirmation (assert/expect)
list.action.ts	80.68%	✅ ❌

Summary by CodeRabbit

• Bug Fixes

  • Improved list action handling in the markdown editor to preserve cursor position when editing list items
  • Enhanced list prefix detection for more robust markdown formatting

• Tests

  • Added test case to verify cursor position stability during list item editing

[coderabbitai]

Walkthrough

The pull request addresses an issue with text cursor positioning when editing list items in a markdown editor. The changes involve modifying the ListAction class in the Monaco editor to prevent the cursor from jumping to the end of the line during text editing. A corresponding test case has been added to verify the cursor position remains intact when performing list-related actions.

Changes

File	Change Summary
src/main/webapp/app/shared/monaco-editor/model/actions/list.action.ts	- Changed position declaration from let to const - Added early return condition for specific cursor scenarios - Slightly modified regex for list prefix detection
src/test/javascript/spec/component/shared/metis/postings-markdown-editor/postings-markdown-editor.component.spec.ts	- Added new test case to verify cursor position preservation during list item editing

Assessment against linked issues

Objective	Addressed	Explanation
Prevent cursor jumping to end of line when editing list text [#10133]	✅
Maintain cursor position during list item modifications	✅

Possibly related PRs

• Communication: Fix an issue with list formatting in Markdown #9925: Enhances list creation functionality with automatic prefixing
• Communication: Add additional input formatting options #9657: Introduces additional input formatting options including bulleted lists

Suggested labels

ready to merge

Suggested reviewers

• HawKhiem
• SimonEntholzer
• sachmii
• florian-glombik
• az108

---

📜 Recent review details

Configuration used: .coderabbit.yaml
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 1543e3e and 0453d9b.

📒 Files selected for processing (2)

• src/main/webapp/app/shared/monaco-editor/model/actions/list.action.ts (1 hunks)
• src/test/javascript/spec/component/shared/metis/postings-markdown-editor/postings-markdown-editor.component.spec.ts (1 hunks)

🧰 Additional context used

📓 Path-based instructions (2)

src/main/webapp/app/shared/monaco-editor/model/actions/list.action.ts (1)

Pattern src/main/webapp/**/*.ts: angular_style:https://angular.io/guide/styleguide;methods_in_html:false;lazy_loading:true;code_reuse:true;tests:meaningful;types:PascalCase;enums:PascalCase;funcs:camelCase;props:camelCase;no_priv_prefix:true;strings:single_quotes;localize:true;btns:functionality;links:navigation;icons_text:newline;labels:associate;code_style:arrow_funcs,curly_braces,open_braces_same_line,indent_4;memory_leak_prevention:true;routes:naming_schema;chart_framework:ngx-charts;responsive_layout:true

src/test/javascript/spec/component/shared/metis/postings-markdown-editor/postings-markdown-editor.component.spec.ts (1)

Pattern src/test/javascript/spec/**/*.ts: jest: true; mock: NgMocks; bad_practices: avoid_full_module_import; perf_improvements: mock_irrelevant_deps; service_testing: mock_http_for_logic; no_schema: avoid_NO_ERRORS_SCHEMA; expectation_specificity: true; solutions: {boolean: toBeTrue/False, reference: toBe, existence: toBeNull/NotNull, undefined: toBeUndefined, class_obj: toContainEntries/toEqual, spy_calls: {not_called: not.toHaveBeenCalled, once: toHaveBeenCalledOnce, with_value: toHaveBeenCalledWith|toHaveBeenCalledExactlyOnceWith}}

⏰ Context from checks skipped due to timeout of 90000ms (1)

• GitHub Check: Codacy Static Code Analysis

🔇 Additional comments (2)

src/main/webapp/app/shared/monaco-editor/model/actions/list.action.ts (1)

82-87: LGTM! The cursor position fix looks good.

The changes effectively prevent the cursor from jumping to the end of the line during text editing by adding an early return condition when no text is selected and the cursor is within the line length.

src/test/javascript/spec/component/shared/metis/postings-markdown-editor/postings-markdown-editor.component.spec.ts (1)

586-606: LGTM! Comprehensive test coverage for cursor position fix.

The test case thoroughly verifies that:

1. The cursor position remains intact during list text editing
2. No unnecessary text replacements occur
3. The cursor stays at the correct column position

✨ Finishing Touches

• 📝 Generate Docstrings (Beta)

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[anian03]

Tested on TS6, did not notice any issues with the cursor position

[eylulnc]

Tested in TS6, testing session. Work as expected ✅

[FelberMartin]

Tested on TS6, the described bug is fixed!

[HawKhiem]

Tested on TS6. No problem with cursor behavior was found

[julian-wls]

Tested on TS6 during session. Didn't notice any cursor jump 👍

[PaRangger]

Tested on TS6, works now. 😄 The only thing i noticed is that if you click again on the "list" button while editing the list it now does not jump to the end of the list. I think that was the behaviour the previous code was trying to achieve, but I don't think its a important use case.

[alekspetrov9e]

There is no problem with the cursor.Tested on TS4

[ItsaaaMeMario]

Tested on TS4, the cursor works correctly.