Sourcemaps always report position 0
smcenlly opened this issue · 4 comments
In this function the sourcemap positions are always returned as position 0. This breaks mapping back to the original source and coverage reporting.
transformWithMap(code: string, _id: string) {
const generated = this.transform(code, _id)
if (generated) {
const ms = new MagicString(code, { filename: _id })
ms.overwrite(0, code.length, generated)
return {
code: ms.toString(),
map: ms.generateMap({ hires: true }),
}
}
}A simpler reproducible example (effectively the same code):
import MagicString from 'magic-string';
const code = `const answer = 42;\n\nconsole.log("The answer is", answer);`;
const generated = code;
const ms = new MagicString(code, { filename: 'test.ts' })
ms.overwrite(0, code.length, generated)
console.log(ms.generateMap({ hires: true }));Returns:
SourceMap {
version: 3,
file: undefined,
sources: [ '' ],
sourcesContent: undefined,
names: [],
mappings: 'AAAA;AAAA'
}
AAAA is position 0 for both statements.
In this function the sourcemap positions are always returned as position 0. This breaks mapping back to the original source and coverage reporting.
transformWithMap(code: string, _id: string) { const generated = this.transform(code, _id) if (generated) { const ms = new MagicString(code, { filename: _id }) ms.overwrite(0, code.length, generated) return { code: ms.toString(), map: ms.generateMap({ hires: true }), } } }A simpler reproducible example (effectively the same code):
import MagicString from 'magic-string'; const code = `const answer = 42;\n\nconsole.log("The answer is", answer);`; const generated = code; const ms = new MagicString(code, { filename: 'test.ts' }) ms.overwrite(0, code.length, generated) console.log(ms.generateMap({ hires: true }));Returns:
SourceMap { version: 3, file: undefined, sources: [ '' ], sourcesContent: undefined, names: [], mappings: 'AAAA;AAAA' }
AAAAis position 0 for both statements.
It seems adding if condition can fix this:
import MagicString from 'magic-string';
const code = `const answer = 42;\n\nconsole.log("The answer is", answer);`;
const generated = code;
const ms = new MagicString(code, { filename: 'test.ts' })
if (code !== generated) {
ms.overwrite(0, code.length, generated);
}
console.log(ms.generateMap({ hires: true }));Returns:
SourceMap {
version: 3,
file: undefined,
sources: [ '' ],
sourcesContent: undefined,
names: [],
mappings: 'AAAA,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC;AAClB,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC,CAAC'
}@cookabc - it's not really a fix... it's a fix for the case where the transformed code is the same as the original. I expect in this case, the unplugin processor hasn't done the work it may have needed to do.
Regardless, it's probably a good interim fix for when unplugin doesn't modify the code but it doesn't address the issue for when unplugin does modify the code.
@cookabc - it's not really a fix... it's a fix for the case where the transformed code is the same as the original. I expect in this case, the unplugin processor hasn't done the work it may have needed to do.
Regardless, it's probably a good interim fix for when unplugin doesn't modify the code but it doesn't address the issue for when unplugin does modify the code.
After some investigation, I believe this might be a rather difficult one than a good first issue
Is there any plan to fix this soon? Interestingly enough, a second plugin I found that provides similar functionality, has this problem too: LZS911/vite-plugin-conditional-compile#5