vue3-yuanma/packages/shared/src/codeframe.ts

40 lines
1.1 KiB
TypeScript

const range: number = 2
export function generateCodeFrame(
source: string,
start = 0,
end = source.length
): string {
const lines = source.split(/\r?\n/)
let count = 0
const res: string[] = []
for (let i = 0; i < lines.length; i++) {
count += lines[i].length + 1
if (count >= start) {
for (let j = i - range; j <= i + range || end > count; j++) {
if (j < 0 || j >= lines.length) continue
const line = j + 1
res.push(`${line}${' '.repeat(3 - String(line).length)}| ${lines[j]}`)
const lineLength = lines[j].length
if (j === i) {
// push underline
const pad = start - (count - lineLength) + 1
const length = Math.max(
1,
end > count ? lineLength - pad : end - start
)
res.push(` | ` + ' '.repeat(pad) + '^'.repeat(length))
} else if (j > i) {
if (end > count) {
const length = Math.max(Math.min(end - count, lineLength), 1)
res.push(` | ` + '^'.repeat(length))
}
count += lineLength + 1
}
}
break
}
}
return res.join('\n')
}