Refactor: Change SequenceDB to class based architecture.

[saurabhg772244]

📑 Summary

• Refactors the existing sequenceDb implementation from a functional approach to a class-based architecture to improve code organization, maintainability, and extensibility.
• Return a new DB object when diagramObject.db is called.
• Introduces new SequenceDB class to encapsulate database operations and state
• Migrates existing functions to class methods
• Maintains existing API interface for backwards compatibility
• Following functions still uses common DB:
  • apply
  • parseMessage
  • parseBoxData
  • LINETYPE
  • PLACEMENT
  • setDiagramTitle
  • setAccTitle
  • setAccDescription
• Reason why above functions still uses common DB: Refactor: Change flowDB to class based architecture. #6161 (comment)
• Added unique IDs for messages during parsing. Previously, IDs were assigned during rendering, which caused issues for diagrams since message operations relied on IDs.
• Updated unit tests to support unique DB instances instead of shared DB.

Resolves #

📏 Design Decisions

• The sequenceDb module previously relied on functions and global variables. Consequently, each call to mermaid.parse or mermaid.render resulted in changes to global variables.
• This behavior caused issues when rendering multiple diagrams using the same Mermaid API, as the database object (DB) for the diagrams would get mixed up.
• To address this, sequenceDb was refactored into a class-based structure. This change ensures that each diagramObject.db call creates a new instance of the database (DB), preventing conflicts between diagrams.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added necessary unit/e2e tests.
• 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• 🦋 If your PR makes a change that should be noted in one or more packages' changelogs, generate a changeset by running pnpm changeset and following the prompts. Changesets that add features should be minor and those that fix bugs should be patch. Please prefix changeset messages with feat:, fix:, or chore:.

[changeset-bot]

🦋 Changeset detected

Latest commit: 5857953

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
mermaid	Patch

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commit: 5857953

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 581 lines in your changes missing coverage. Please review.

Project coverage is 4.46%. Comparing base (52532a7) to head (5857953).
Report is 18 commits behind head on develop.

Files with missing lines	Patch %	Lines
...ckages/mermaid/src/diagrams/sequence/sequenceDb.ts	0.00%	567 Missing ⚠️
...s/mermaid/src/diagrams/sequence/sequenceDiagram.ts	0.00%	14 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           develop   #6272   +/-   ##
=======================================
  Coverage     4.46%   4.46%           
=======================================
  Files          385     385           
  Lines        54276   54275    -1     
  Branches       598     598           
=======================================
  Hits          2425    2425           
+ Misses       51851   51850    -1     

Flag	Coverage Δ
unit	4.46% <0.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
.../mermaid/src/diagrams/sequence/sequenceRenderer.ts	0.00% <ø> (ø)
...s/mermaid/src/diagrams/sequence/sequenceDiagram.ts	0.00% <0.00%> (ø)
...ckages/mermaid/src/diagrams/sequence/sequenceDb.ts	0.00% <0.00%> (ø)

[aloisklink]

The this.setWrap(getConfig().wrap); in the constructor seems to be the only thing I'm a bit nervous about, the rest of the PR seems good to me (as long as the visual regression tests come back green ✔️)

[saurabhg772244]

@aloisklink i think we can refactor it into separate PR

[sidharthv96]

@saurabhg772244 please sync with develop, argos should work now.

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Build	Status	Details	Updated (UTC)
default (Inspect)	✅ No changes detected	-	Feb 19, 2025, 6:08 AM