Add DSL node styling support

[swiftlysingh]

Summary

• add DSL parser support for inline node style attributes and @node style blocks
• merge block defaults and inline overrides into deduplicated graph nodes
• document the new DSL styling syntax and cover parsing/generation behavior with tests

Testing

• npm run build
• npm run test:run -- tests/unit/parser/dsl-parser.test.ts

Implements #22

  

Summary by CodeRabbit

• New Features

  • Added node styling capabilities with inline @key:value attributes and reusable @node style blocks.
  • Supported style properties include fillStyle, backgroundColor, strokeColor, strokeWidth, strokeStyle, roughness, and opacity with defined precedence rules.

• Documentation

  • Updated README and man page with comprehensive node styling syntax documentation and examples.

• Tests

  • Added extensive test coverage for node styling parsing, validation, and output generation.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

A new node styling feature is introduced to the DSL parser through a preprocessing pass that recognizes @node block directives with style key-value pairs and inline @key:value attributes on node labels. Styles are validated, parsed (with numeric and enum conversions), and merged with block-level defaults overridden by inline attributes. Documentation is updated to describe the syntax and merge precedence rules.

Changes

Cohort / File(s)	Summary
Documentation README.md, man/excalidraw-cli.1	Extended DSL syntax documentation with new inline styled-node form [Label @key:value ...] and @node block directives; added "Node Styling" sections describing supported style keys and merge precedence.
Parser Implementation src/parser/dsl-parser.ts	Added preprocessing pass to recognize and validate @node style blocks; extended node token parsing to extract inline @key:value attributes; implemented mergeNodeStyles function for applying block defaults and inline overrides to nodes during creation.
Test Coverage tests/unit/parser/dsl-parser.test.ts	Added comprehensive test cases for inline style parsing, @node block directives, merge behavior, style validation (unsupported keys, invalid values), and integration with layout and code generation.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~45 minutes

Poem

🐰 Through @key and styled-node lands I hop,
Where inline colors never stop,
Block defaults dance with inline grace,
Each rectangle finds its place!
A parser's art, a rabbit's delight,
Node styling makes the DSL bright! ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 23.08% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'Add DSL node styling support' directly and concisely summarizes the main change: adding node styling capabilities to the DSL parser, which is the core focus of the changeset.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cursor/custom-fonts-support-95e2

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[Copilot]

Pull request overview

Adds DSL support for styling nodes via inline @key:value attributes and @node style blocks, propagating those styles through layout and Excalidraw generation.

Changes:

• Extend DSL parsing to recognize inline node style attributes and @node style blocks, merging defaults and overrides into deduplicated nodes.
• Add validation for supported style keys and allowed values.
• Document the new styling syntax and add unit tests covering parsing, merging, validation, and generation.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
tests/unit/parser/dsl-parser.test.ts	Adds test coverage for inline styles, @node blocks, precedence/merging rules, validation errors, and style propagation into generated elements.
src/parser/dsl-parser.ts	Implements style parsing/validation, @node block preprocessing, and merges block + inline styles into deduplicated graph nodes.
README.md	Documents inline style attributes, @node blocks, supported keys/values, and precedence rules.
man/excalidraw-cli.1	Updates CLI man page to include node styling syntax and examples.

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[Copilot]

preprocessNodeStyleBlocks only detects node-style blocks when the trimmed line starts with the literal string "@node " (space). If the DSL uses a tab or multiple spaces after @node (e.g. @node\t[Login]), the block will be ignored and tokenized as a normal directive instead, so styles won’t be applied. Consider matching @node with a whitespace regex (e.g. /^@node\b/) and then parsing the selector after any whitespace to make the directive robust and consistent with other directive parsing.

Suggested change

	if (!trimmed.startsWith('@node ')) {
	outputLines.push(line);
	continue;
	}
	const selector = trimmed.slice('@node'.length).trim();
	const nodeDirectiveMatch = trimmed.match(/^@node\s+(.+)$/);
	if (!nodeDirectiveMatch) {
	outputLines.push(line);
	continue;
	}
	const selector = nodeDirectiveMatch[1].trim();

[Copilot]

The man page describes [Label @key:value ...] as a "Rectangle node with inline style attributes" and shows @node [Label], but inline styles and @node selectors are supported for other node syntaxes too (e.g. {...}, (...), [[...]]). Updating this wording/examples to refer to “shape nodes” (or “any node selector”) would avoid misleading users about the feature scope.

Suggested change

	Rectangle node with inline style attributes.
	.TP
	.BI "@node [Label]"
	Start a node-style block followed by indented
	Shape node with inline style attributes.
	.TP
	.BI "@node <node-selector>"
	Start a node-style block for a node selector followed by indented