From 26105034da4fcce7ac883c899d781f016559310d Mon Sep 17 00:00:00 2001 From: ruki Date: Thu, 8 Nov 2018 00:38:48 +0800 Subject: switch to vuepress --- .../lib/templateCompilerModules/srcset.ts | 66 ++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 node_modules/@vue/component-compiler-utils/lib/templateCompilerModules/srcset.ts (limited to 'node_modules/@vue/component-compiler-utils/lib/templateCompilerModules/srcset.ts') diff --git a/node_modules/@vue/component-compiler-utils/lib/templateCompilerModules/srcset.ts b/node_modules/@vue/component-compiler-utils/lib/templateCompilerModules/srcset.ts new file mode 100644 index 00000000..7cb7544e --- /dev/null +++ b/node_modules/@vue/component-compiler-utils/lib/templateCompilerModules/srcset.ts @@ -0,0 +1,66 @@ +// vue compiler module for transforming `img:srcset` to a number of `require`s + +import { urlToRequire, ASTNode } from './utils' + +interface ImageCandidate { + require: string + descriptor: string +} + +export default () => ({ + postTransformNode: (node: ASTNode) => { + transform(node) + } +}) + +// http://w3c.github.io/html/semantics-embedded-content.html#ref-for-image-candidate-string-5 +const escapedSpaceCharacters = /( |\\t|\\n|\\f|\\r)+/g + +function transform(node: ASTNode) { + const tags = ['img', 'source'] + + if (tags.indexOf(node.tag) !== -1 && node.attrs) { + node.attrs.forEach(attr => { + if (attr.name === 'srcset') { + // same logic as in transform-require.js + const value = attr.value + const isStatic = + value.charAt(0) === '"' && value.charAt(value.length - 1) === '"' + if (!isStatic) { + return + } + + const imageCandidates: ImageCandidate[] = value + .substr(1, value.length - 2) + .split(',') + .map(s => { + // The attribute value arrives here with all whitespace, except + // normal spaces, represented by escape sequences + const [url, descriptor] = s + .replace(escapedSpaceCharacters, ' ') + .trim() + .split(' ', 2) + return { require: urlToRequire(url), descriptor } + }) + + // "require(url1)" + // "require(url1) 1x" + // "require(url1), require(url2)" + // "require(url1), require(url2) 2x" + // "require(url1) 1x, require(url2)" + // "require(url1) 1x, require(url2) 2x" + const code = imageCandidates + .map( + ({ require, descriptor }) => + `${require} + "${descriptor ? ' ' + descriptor : ''}, " + ` + ) + .join('') + .slice(0, -6) + .concat('"') + .replace(/ \+ ""$/, '') + + attr.value = code + } + }) + } +} -- cgit v1.2.3