add @babel/plugin-syntax-dynamic-import

[bourgeoa]

PR: Fix JSON-LD Dynamic Import Broken by Babel Transpilation

Problem

The jsonldparser.js uses dynamic import to load the jsonld module:

const jsonld = await import('jsonld')

This works perfectly in vanilla Node.js, but Babel's transpilation breaks it:

• Babel's _interopRequireWildcard wrapper causes the module to load as an empty object {}
• Result: TypeError: jsonld.flatten is not a function

[Copilot]

Pull request overview

This PR addresses a critical issue where JSON-LD dynamic imports were failing due to Babel transpilation issues. The fix involves two main approaches: configuring Babel to preserve dynamic imports in ESM builds and adding fallback logic to handle both ESM and CommonJS module formats.

Changes:

• Added @babel/plugin-syntax-dynamic-import plugin and configured Babel to exclude dynamic import transformation in ESM builds
• Updated jsonldparser.js to handle both ESM (jsonld.default) and CommonJS (jsonld) module formats
• Added comprehensive RDFa parsing tests that exercise the JSON-LD parser functionality

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
.babelrc	Added dynamic import syntax plugin and excluded transform in ESM config
package.json	Added @babel/plugin-syntax-dynamic-import dependency
package-lock.json	Lock file updates for new dependency
src/jsonldparser.js	Added ESM/CommonJS compatibility with fallback logic
tests/unit/parse-test.js	Added RDFa test suite with JSON-LD serialization/parsing tests

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[Copilot]

The exclude configuration uses "proposal-dynamic-import" but this may not match the actual plugin name used by @babel/preset-env version 7.28.x. The plugin was renamed from "proposal-dynamic-import" to "@babel/plugin-transform-dynamic-import" in earlier Babel 7 versions. You should verify this exclusion is working as intended by checking if dynamic imports are preserved in the ESM build output. The correct value might need to be "transform-dynamic-import" or "@babel/plugin-transform-dynamic-import" depending on the preset-env version.

Suggested change

	{ "exclude": ["proposal-dynamic-import"],
	{ "exclude": ["transform-dynamic-import"],

[Copilot]

Adding @babel/plugin-syntax-dynamic-import may be unnecessary with @babel/preset-env version 7.28.x, as the preset already includes dynamic import syntax support. The plugin only enables parsing of dynamic import syntax and doesn't prevent transformation. To preserve dynamic imports in the output, you should focus on correctly excluding the transform plugin in the preset-env configuration (line 16 of .babelrc) rather than adding this syntax plugin. Consider removing this plugin and verifying that the exclude configuration alone solves the issue.

Suggested change

	"@babel/plugin-proposal-class-properties",
	"@babel/plugin-syntax-dynamic-import"
	"@babel/plugin-proposal-class-properties"

[Copilot]

The variable ttlContent is declared at the top but only assigned and used in the first test. It should be declared inside the specific test where it's used (line 556) to improve test isolation and clarity.

[bourgeoa]

@copilot open a new pull request to apply changes based on this feedback

[Copilot]

@bourgeoa I've opened a new pull request, #757, to work on those changes. Once the pull request is ready, I'll request review from you.