This PR adds two things:
`--debug-print-doc` command that prints the formatted doc
```js
echo "<div><</div>" | ./bin/prettier.js --stdin --debug-print-doc
[
groupConditional(
group([
group([ "<", "div", group([ indent(2, []), softline() ]), ">" ]),
"<",
"</",
"div",
">"
]),
[
group([
group([ "<", "div", group([ indent(2, []), softline() ]), ">" ]),
"<",
"</",
"div",
">"
]),
group([
group([ "<", "div", group([ indent(2, []), softline() ]), ">" ]),
indent(2, groupBreak([ hardline(), "<" ])),
hardline(),
"</",
"div",
">"
])
]
),
";",
hardline()
];
```
The ability to view the IR in real time on the browser display:
The way it works is pretty cool, we take the doc IR and print a valid JavaScript string out of it, that we then send to prettier in order to make it look good :)
The previous API was inconsistent. The new one is
```js
--parser flow
--parser babylon
{parser: 'flow'}
{parser: 'babylon'}
```
if we ever want to add new parsers in the future it'll allow that more easily.
I put a console.log in parser.js in both functions and tested that the test suite worked both with and without the change in run_spec. I also tested that both the previous and new command line options are working.
At some point in the future we'll likely want to get rid of the old api but might as well keep supporting it so we don't break anyone for now.
Extracted out parse and attachComments. Moved the options normalization in the exported function.
This way, we have a super clean format function :)
```js
function format(text, opts) {
const ast = parse(text, opts);
attachComments(text, ast, opts)
const doc = printAstToDoc(ast, opts)
const str = printDocToString(doc, opts.printWidth)
return str;
}
```
- doc-printer.js is now the direct implementation of the Wadler paper
- doc-builders.js are a lot of utils to generate the IR the above file needs
- doc-utils.js are small utils to traverse list of docs.
The Nuclide codebase uses features that are still proposals which require a flag to be enabled. Babylon parses them fine without any flags.
Let's enable them by default as it doesn't cost much, you either are using those features and you don't want the parser to break, or you are not and you don't care.
After this and #218, none of the nuclide files are throwing exceptions! (yay!)
When looking into adding a test, I realized that the logic was inside of bin/prettier.js and therefore only applying to the cli. Moving it to index.js and adding a test so that it's more robust :)
Christopher Chedeau
