78 lines
1.9 KiB
TypeScript
78 lines
1.9 KiB
TypeScript
|
function addReactImport(j, root) {
|
||
|
// We create an import specifier, this is the value of an import, eg:
|
||
|
// import React from 'react'
|
||
|
// The specifier would be `React`
|
||
|
const ReactDefaultSpecifier = j.importDefaultSpecifier(j.identifier('React'))
|
||
|
|
||
|
// Check if this file is already importing `react`
|
||
|
// so that we can attach `React` to the existing import instead of creating a new `import` node
|
||
|
const originalReactImport = root.find(j.ImportDeclaration, {
|
||
|
source: {
|
||
|
value: 'react',
|
||
|
},
|
||
|
})
|
||
|
if (originalReactImport.length > 0) {
|
||
|
// Check if `React` is already imported. In that case we don't have to do anything
|
||
|
if (originalReactImport.find(j.ImportDefaultSpecifier).length > 0) {
|
||
|
return
|
||
|
}
|
||
|
|
||
|
// Attach `React` to the existing `react` import node
|
||
|
originalReactImport.forEach((node) => {
|
||
|
node.value.specifiers.unshift(ReactDefaultSpecifier)
|
||
|
})
|
||
|
return
|
||
|
}
|
||
|
|
||
|
// Create import node
|
||
|
// import React from 'react'
|
||
|
const ReactImport = j.importDeclaration(
|
||
|
[ReactDefaultSpecifier],
|
||
|
j.stringLiteral('react')
|
||
|
)
|
||
|
|
||
|
// Find the Program, this is the top level AST node
|
||
|
const Program = root.find(j.Program)
|
||
|
// Attach the import at the top of the body
|
||
|
Program.forEach((node) => {
|
||
|
node.value.body.unshift(ReactImport)
|
||
|
})
|
||
|
}
|
||
|
|
||
|
export default function transformer(file, api, options) {
|
||
|
const j = api.jscodeshift
|
||
|
const root = j(file.source)
|
||
|
|
||
|
const hasReactImport = (r) => {
|
||
|
return (
|
||
|
r.find(j.ImportDefaultSpecifier, {
|
||
|
local: {
|
||
|
type: 'Identifier',
|
||
|
name: 'React',
|
||
|
},
|
||
|
}).length > 0
|
||
|
)
|
||
|
}
|
||
|
|
||
|
const hasReactVariableUsage = (r) => {
|
||
|
return (
|
||
|
r.find(j.MemberExpression, {
|
||
|
object: {
|
||
|
type: 'Identifier',
|
||
|
name: 'React',
|
||
|
},
|
||
|
}).length > 0
|
||
|
)
|
||
|
}
|
||
|
|
||
|
if (hasReactImport(root)) {
|
||
|
return
|
||
|
}
|
||
|
|
||
|
if (hasReactVariableUsage(root)) {
|
||
|
addReactImport(j, root)
|
||
|
}
|
||
|
|
||
|
return root.toSource(options)
|
||
|
}
|