feat(logger): add opt-in multi-line log alignment

[a145789]

feat(logger): add opt-in multi-line log alignment

Add alignMultiline option to createLogger (default: false,
non-breaking). When enabled, continuation lines of multi-line
messages are indented to align with the first line's content
column (label + prefix), so multi-line output reads as a
contiguous block instead of wrapping back to column 0.

Changes

• src/types.ts: add alignMultiline?: boolean to Options.
• src/utils.ts: add stripAnsi; use it in isErrorStackMessage
  so the stack regex still matches ANSI-grayed lines.
• src/createLogger.ts: extract LABEL_WIDTH constant; after
  text is assembled, indent continuation lines to
  LABEL_WIDTH + 1 + (prefix length + 1). Skip the first line,
  blank lines, and stack-like lines (only at level === 'error').
  Error objects are exempt entirely.
• tests: add new tests for the feature only; existing tests and
  snapshots are untouched.

Expected output

Without prefix:

info    User profile updated:
        - Name: John Doe
        - Email: john@example.com

With prefix [web]:

info    [web] User profile updated:
              - Name: John Doe
              - Email: john@example.com

Error stacks stay top-aligned:

error   Something failed:
        - reason A
    at /rslog/foo/bar.js:29:0
        - reason B

Closes #51

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: e9fe137b-cbdd-4afa-bdd2-d81ccc5f4629

📥 Commits

Reviewing files that changed from the base of the PR and between 3df572a and a53084d.

📒 Files selected for processing (3)

• src/createLogger.ts
• src/utils.ts
• tests/logger.test.ts

🚧 Files skipped from review as they are similar to previous changes (2)

• tests/logger.test.ts
• src/createLogger.ts

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📝 Walkthrough

Walkthrough

The PR adds an alignMultiline option to the logger. A new alignMultiline?: boolean property is added to the Options interface. A stripAnsi helper is introduced in src/utils.ts, and isErrorStackMessage is updated to strip ANSI codes before pattern matching. In createLogger, the options destructuring is expanded to include alignMultiline; label tracking is refactored with hasLabel and isErrorObject flags. When alignMultiline is enabled and a non-Error message contains newlines, subsequent non-empty lines are indented by LABEL_WIDTH plus the ANSI-stripped prefix length, except error-stack lines at error level which remain top-aligned. Tests and a preview demo are added to cover all alignment scenarios.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: opt-in multi-line log alignment.
Description check	✅ Passed	The description matches the code changes and explains the new alignMultiline behavior accurately.
Linked Issues check	✅ Passed	The PR implements #51 by adding alignMultiline, indenting continuation lines, handling error stacks, and adding tests.
Out of Scope Changes check	✅ Passed	The changes stay focused on multiline alignment support and related test/util updates, with no clear unrelated scope creep.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[coderabbitai]

🧹 Nitpick comments (1)

src/utils.ts (1)

6-6: 🧹 Nitpick | 🔵 Trivial | ⚡ Quick win

Prefer standard escape sequence notation.

Consider using \x1b instead of String.fromCharCode(27) for the ESC character—it's more idiomatic and immediately recognizable.

♻️ Suggested refactor

-const ANSI_REGEXP = new RegExp(`${String.fromCharCode(27)}\\[[0-9;]*m`, 'g');
+const ANSI_REGEXP = /\x1b\[[0-9;]*m/g;

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@src/utils.ts` at line 6, The ANSI_REGEXP constant uses
String.fromCharCode(27) to represent the ESC character, which is less idiomatic
than the standard escape sequence notation. Replace the String.fromCharCode(27)
call in the ANSI_REGEXP definition with the \x1b escape sequence, which is more
immediately recognizable and follows JavaScript conventions for representing
control characters.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@src/utils.ts`:
- Line 6: The ANSI_REGEXP constant uses String.fromCharCode(27) to represent the
ESC character, which is less idiomatic than the standard escape sequence
notation. Replace the String.fromCharCode(27) call in the ANSI_REGEXP definition
with the \x1b escape sequence, which is more immediately recognizable and
follows JavaScript conventions for representing control characters.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 95d06d21-d4c9-4da2-aeb6-153813037fc4

📥 Commits

Reviewing files that changed from the base of the PR and between 25dc20d and 3df572a.

⛔ Files ignored due to path filters (1)

• tests/__snapshots__/logger.test.ts.snap is excluded by !**/*.snap

📒 Files selected for processing (5)

• preview/index.ts
• src/createLogger.ts
• src/types.ts
• src/utils.ts
• tests/logger.test.ts

[chenjiahan]

Sorry I missed this, could you resolve the conflicts?

[a145789]

Sorry I missed this, could you resolve the conflicts?

Resolved

[chenjiahan]

Thank you!