carbon-custom-elements/es/globals/directives/spread.d.ts.map

A Carbon Design System variant that's as easy to use as native HTML elements, with no framework tax, no framework silo.

{"version":3,"sources":["globals/directives/spread.ts"],"names":[],"mappings":"AAAA;;;;;;;GAOG;AAEH,OAAO,EAAE,IAAI,EAA2B,MAAM,UAAU,CAAC;AAEzD,MAAM,WAAW,cAAc;IAC7B,QAAQ,EAAE,IAAI,EAAE,MAAM,GAAG,MAAM,CAAC;CACjC;AAQD;;;;;;GAMG;AACH,QAAA,MAAM,MAAM,0DA6BV,CAAC;AAEH,eAAe,MAAM,CAAC","file":"spread.d.ts","sourcesContent":["/**\n * @license\n *\n * Copyright IBM Corp. 2019\n *\n * This source code is licensed under the Apache-2.0 license found in the\n * LICENSE file in the root directory of this source tree.\n */\n\nimport { Part, PropertyPart, directive } from 'lit-html';\n\nexport interface AttributesInfo {\n  readonly [name: string]: string;\n}\n\n/**\n * Stores the ClassInfo object applied to a given AttributePart.\n * Used to unset existing values when a new ClassInfo object is applied.\n */\nconst attributesMapCache = new WeakMap();\n\n/**\n * A directive that applies attributes from a key-value pairs.\n * This must be used in the `...` name and must be the only part used in the attribute.\n * It applies the key-value pairs in the `attributesInfo` argument\n * and sets them as attribute name/value pairs.\n * @param classInfo The key-value pair to be set as the attribute name/value pairs.\n */\nconst spread = directive((attributesInfo: AttributesInfo) => (part: Part) => {\n  // The first character of `...` is interpreted as one for `PropertyPart`\n  if (!(part instanceof PropertyPart) || part.committer.name !== '..' || part.committer.parts.length > 1) {\n    throw new Error('The `spread` directive must be used in with `...` name and must be the only part in the attribute.');\n  }\n\n  const { committer } = part;\n  const { element } = committer;\n\n  // Removes old attributes that are no longer there\n  const oldAttributesInfo = attributesMapCache.get(part);\n  if (oldAttributesInfo) {\n    Object.keys(oldAttributesInfo).forEach(name => {\n      if (!(name in attributesInfo)) {\n        element.removeAttribute(name);\n      }\n    });\n  }\n\n  // Adds new attributes\n  Object.keys(attributesInfo).forEach(name => {\n    const value = attributesInfo[name];\n    if ((!oldAttributesInfo || !Object.is(value, oldAttributesInfo[name])) && typeof value !== 'undefined') {\n      element.setAttribute(name, value);\n    }\n  });\n\n  // Updates the cache\n  attributesMapCache.set(part, attributesInfo);\n});\n\nexport default spread;\n"]}