migrate tool ignores parser

Describe the bug When running sb migrate with a parser argument (eg sb migrate --parser=flow storiesof-to-csf --glob 'components/stories/*.js'), the parser is ignored.

To Reproduce Steps to reproduce the behavior:

1. Create a stories file with flowtype annotations
2. Run sb migrate --parser=flow storiesof-to-csf --glob 'components/stories/*.js'

Expected behavior The migrate tool converts my stories to CSF format

Screenshots Failure due to babel parser not being able to parse flow types:

 ERR components/stories/midrollToolbar.js Transformation error
SyntaxError: Unexpected token, expected ";" (7:11)
    at _class.raise (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:776:15)
    at _class.unexpected (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:2079:16)
    at _class.semicolon (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:2063:40)
    at _class.parseVarStatement (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:4413:10)
    at _class.parseStatementContent (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:4012:21)
    at _class.parseStatement (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:3962:17)
    at _class.parseBlockOrModuleBlockBody (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:4513:23)
    at _class.parseBlockBody (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:4500:10)
    at _class.parseBlockBody (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:5462:44)
    at _class.parseTopLevel (/Users/jon/.config/yarn/global/node_modules/jscodeshift/node_modules/babylon/lib/index.js:3938:10)

Additional context

The parser option is passed here - https://github.com/storybookjs/storybook/blob/dfe9eb7efc73cd677f44c1ebb3f052ef68b4a3f9/lib/cli/bin/generate.js#L68 - and then ignored here - https://github.com/storybookjs/storybook/blob/dfe9eb7efc73cd677f44c1ebb3f052ef68b4a3f9/lib/cli/lib/migrate.js#L3.

I tried to naively fix it by passing the parserOption through to runCodeMod, but it dies at the prettier stage:

 ERR components/stories/midrollToolbar.js Transformation error (Cannot read property 'process' of undefined)
TypeError: Cannot read property 'process' of undefined
    at buffer (/Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:42536)
    at mGt (/Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:1429771)
    at e (/Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:393)
    at default (/Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:19587)
    at /Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:16
    at Object.prettierPlugins (/Users/jon/Developer/web/webpack/node_modules/prettier/parser-flow.js:1:139)
    at Module._compile (internal/modules/cjs/loader.js:816:30)
    at Module._compile (/Users/jon/Developer/web/webpack/node_modules/pirates/lib/index.js:99:24)
    at Module._extensions..js (internal/modules/cjs/loader.js:827:10)
    at Object.newLoader [as .js] (/Users/jon/Developer/web/webpack/node_modules/pirates/lib/index.js:104:7)

[mbylstra]

Yes, thanks - I also found that. But then I ran into further problems with the transform when it’s run in tsx mode: I opened an issue about this: https://github.com/storybookjs/storybook/issues/9669

[shilman]

Fixed in #12453 and released in 6.0. Closing!