Function getSourceForImportExternal

lib/ExternalModule.js:275–331

(
	moduleAndSpecifiers,
	runtimeTemplate,
	dependencyMeta
)

 * @returns {SourceData} the generated source
 */
const getSourceForImportExternal = (
	moduleAndSpecifiers,
	runtimeTemplate,
	dependencyMeta
) => {
	const baseImportName = runtimeTemplate.outputOptions.importFunctionName;
	if (
		!runtimeTemplate.supportsDynamicImport() &&
		(baseImportName === "import" || baseImportName === "module-import")
	) {
		throw new Error(
			"The target environment doesn't support 'import()' so it's not possible to use external type 'import'"
		);
	}
	const phase = dependencyMeta && dependencyMeta.phase;
	// `import.defer(…)` and `import.source(…)` are only valid forms of the
	// native `import(…)` function, so we only emit the phase suffix when the
	// importFunctionName is the default `"import"`.
	const importName =
		baseImportName === "import" && ImportPhaseUtils.isDefer(phase)
			? "import.defer"
			: baseImportName === "import" && ImportPhaseUtils.isSource(phase)
				? "import.source"
				: baseImportName;
	const attributes =
		dependencyMeta && dependencyMeta.attributes
			? dependencyMeta.attributes._isLegacyAssert
				? `, { assert: ${JSON.stringify(
						dependencyMeta.attributes,
						importAssertionReplacer
					)} }`
				: `, { with: ${JSON.stringify(dependencyMeta.attributes)} }`
			: "";
	if (!Array.isArray(moduleAndSpecifiers)) {
		return {
			expression: `${importName}(${JSON.stringify(
				moduleAndSpecifiers
			)}${attributes});`
		};
	}
	if (moduleAndSpecifiers.length === 1) {
		return {
			expression: `${importName}(${JSON.stringify(
				moduleAndSpecifiers[0]
			)}${attributes});`
		};
	}
	const moduleName = moduleAndSpecifiers[0];
	return {
		expression: `${importName}(${JSON.stringify(
			moduleName
		)}${attributes}).then(${runtimeTemplate.returningFunction(
			`module${propertyAccess(moduleAndSpecifiers, 1)}`,
			"module"
		)});`
	};
};