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Configuration error
Configuration error
| export function walk(ast, { enter, leave }) { | |
| visit(ast, null, enter, leave); | |
| } | |
| let shouldSkip = false; | |
| const context = { skip: () => shouldSkip = true }; | |
| export const childKeys = {}; | |
| const toString = Object.prototype.toString; | |
| function isArray(thing) { | |
| return toString.call(thing) === '[object Array]'; | |
| } | |
| function visit(node, parent, enter, leave, prop, index) { | |
| if (!node) return; | |
| if (enter) { | |
| const _shouldSkip = shouldSkip; | |
| shouldSkip = false; | |
| enter.call(context, node, parent, prop, index); | |
| const skipped = shouldSkip; | |
| shouldSkip = _shouldSkip; | |
| if (skipped) return; | |
| } | |
| const keys = node.type && childKeys[node.type] || ( | |
| childKeys[node.type] = Object.keys(node).filter(key => typeof node[key] === 'object') | |
| ); | |
| for (let i = 0; i < keys.length; i += 1) { | |
| const key = keys[i]; | |
| const value = node[key]; | |
| if (isArray(value)) { | |
| for (let j = 0; j < value.length; j += 1) { | |
| value[j] && value[j].type && visit(value[j], node, enter, leave, key, j); | |
| } | |
| } | |
| else if (value && value.type) { | |
| visit(value, node, enter, leave, key, null); | |
| } | |
| } | |
| if (leave) { | |
| leave(node, parent, prop, index); | |
| } | |
| } | |