@storybook/addon-svelte-csf/dist/compiler/post-transform/shared/parameters.js

Allows to write stories in Svelte syntax

import dedent from 'dedent';
import { createASTObjectExpression } from '../../../parser/ast.js';
/**
 * In order to be able to access AST node - {@link Property} - from the {@link ObjectExpression},
 * we need to have its index based on the property name, so the key must be an identifier.
 * NOTE: Reminder, it always returns a number and `-1` means not found.
 */
export function findASTPropertyIndex(options) {
    const { node, name } = options;
    return node.properties.findIndex((p) => p.type === 'Property' && p.key.type === 'Identifier' && p.key.name === name);
}
export const findPropertyParametersIndex = (options) => {
    return findASTPropertyIndex({
        ...options,
        name: 'parameters',
    });
};
export const getParametersProperty = (options) => {
    const { node } = options;
    return node.properties[findPropertyParametersIndex(options)];
};
export const getParametersPropertyValue = (options) => {
    const { filename, component } = options;
    let property = getParametersProperty(options);
    // NOTE: is a getter property - `get parameters()`
    // WARN: This is probably a bad idea. Need second opinion.
    // In the case when attribute _(prop)_ `parameters` was defined by the user in the `<Story />` component,
    // svelte internally will convert provided value into `Proxy`(?) _(I'm guessing on initial research)_.
    // This is some sort of reactivity-optimization(?).
    // The visualization below explains what's going to happen:
    //
    // Before:
    //
    // ```js
    // get parameters() {
    //   return something;
    // }
    //
    // ```js
    // parameters: {
    //   ...something,
    // },
    //
    if (property.kind === 'get' &&
        property.value.type === 'FunctionExpression' &&
        property.value.body.body[0].type === 'ReturnStatement') {
        const properties = [];
        if (property.value.body.body[0].argument) {
            properties.push({
                type: 'SpreadElement',
                argument: property.value.body.body[0].argument,
            });
        }
        property.kind = 'init';
        property.value = createASTObjectExpression(properties);
    }
    if (property.value.type !== 'ObjectExpression') {
        console.warn(dedent `
      Svelte CSF:
        Could not access 'parameters' of ${component ? "Story's prop" : 'defineMeta'}}.
        Expected value to be an object expression.
        Instead it was '${property.value.type}', in: 
        ${filename}
        Property:
        ${JSON.stringify(property, null, 2)}
    `);
        // NOTE: We're emitting a warning when it happens
        return undefined;
    }
    // FIXME: This is a dirty workaround.
    // I couldn't figure out how and where it gets `Object.preventExtension(properties)` enabled, or anything that gives the same effect.
    // There's no possibility to push an element to 'properties' array - throws an error related to "Object is not extensible".
    if (!Object.isExtensible(property.value.properties)) {
        property.value.properties = Array.from(property.value.properties);
    }
    return property.value;
};
export const findPropertyDocsIndex = (options) => {
    return findASTPropertyIndex({
        ...options,
        name: 'docs',
        node: getParametersPropertyValue(options),
    });
};
export const getDocsProperty = (options) => {
    return getParametersPropertyValue(options).properties[findPropertyDocsIndex(options)];
};
export const getDocsPropertyValue = (options) => {
    const { filename, component } = options;
    const property = getDocsProperty(options);
    const { value } = property;
    if (value.type !== 'ObjectExpression') {
        console.warn(dedent `
      Svelte CSF:
        Could not access 'parameters.docs' of ${component ? "Story's prop" : 'defineMeta'}}.
        Expected value to be an object expression.
        Instead it was '${property.value.type}', in: 
        ${filename}
        Property:
        ${JSON.stringify(property, null, 2)}
    `);
        // NOTE: We're emitting a warning when it happens
        return undefined;
    }
    return value;
};
export const findPropertyDescriptionIndex = (options) => {
    return findASTPropertyIndex({
        ...options,
        name: 'description',
        node: getDocsPropertyValue(options),
    });
};
export const getDescriptionProperty = (options) => {
    return getDocsPropertyValue(options).properties[findPropertyDescriptionIndex(options)];
};
export const getDescriptionPropertyValue = (options) => {
    const { filename, component } = options;
    const property = getDescriptionProperty(options);
    const { value } = property;
    if (value.type !== 'ObjectExpression') {
        console.warn(dedent `
      Svelte CSF:
        Could not access 'parameters.docs.description' of ${component ? "Story's prop" : 'defineMeta'}}.
        Expected value to be an object expression.
        Instead it was '${property.value.type}', in: 
        ${filename}
        Property:
        ${JSON.stringify(property, null, 2)}
    `);
        // NOTE: We're emitting a warning when it happens
        return undefined;
    }
    return value;
};