Fixes#5238.
cc @duailibe for the [original change](https://github.com/prettier/prettier/pull/4413). I basically undid that PR because it didn't look to me like `shouldFlatten` made sense as the place to introduce the behavior it was going for, but I might have misunderstood something.
* chore: upgrade Jest
* chore: update snapshots
* chore: lock down babel dependency using invalid syntax
* 2 args to test.skip
* use jest 22 for now
* Revert "2 args to test.skip"
This reverts commit 691fdc3f99e320f2303958f2b503f7b4c93fa455.
* remove snapshot name from matcher
* fix standalone tests skips
Fixes#2777
Since we can't break after `return` and don't add `()` around
ConditionalExpressions' tests, we end up with some weird indentation when
breaking.
* Add test for empty object in logical expression
* Add check for empty object and array in shouldInlineLogicalExpression
* Review fixes, add additional case with function call
* Revert "Remove mutation in `printBinaryishExpressions` (#1067)"
This reverts commit e7312ad7b2.
* Revert "Make it clear what parser was used in each snapshot (#1068)"
This reverts commit 4f7ae4815b.
The root cause is that we're calling `printComments` with an empty string, meaning that the leading/trailing comments are not correctly inserted at the right location.
So, the way to fix it is to call `p => concat(parts)` but because we're mutating the array in place, it doesn't work. We need to mutate it and create a copy. But, the root call is actually checking the shape of the parts array which our code is now breaking...
```js
// Don't include the initial expression in the indentation
// level. The first item is guaranteed to be the first
// left-most expression.
parts.length > 0 ? parts[0] : "",
```
The consequence is that binary expressions are no longer indented if the first expression has a comment (but now it places the comment properly!), which seems like a good trade-off.
I'm not sure if we should merge this one or instead refactor this code such that it doesn't rely on mutation and looking at the shape of the printed tree. `printMemberChain` is a good thing to reference for inspiration.
Fixes#946
Printing the first line of a binary expression next to the `=` leads to weird cases where the first expression is parenthesised and doens't read well with chained conditionals as they don't align well. This makes it behave the same was as `if` tests.
Fixes#863
In #605 I restricted it to binary operations as I didn't know how it would affect boolean operations but it turns out the same technique solves problems that people are reporting. So doesn't make sense to restrict it.
Fixes#824
It seems like precedence for this combination of operators is very unclear to people (myself included) and consistently adding parenthesis there would be good.
Fixes#773
I've been trying to come up with a heuristic to stop putting small elements on a new line and I just realized that all the cases I found out only involved a single binary expression. If there's only a single operation, we can just put them on the same line (if it fits) and it's not going to look weird.
We do the same thing for MemberExpression where we only break if there are more than one ".".
Fixes#583Fixes#503
* new_tests
* move_all_clobbered_tests
* remove all the tests that no longer exist
* re-run flow tests
* Move all the flow tests to tests/flow and prettier to tests/
* Move prettier tests to their own folders
* Add jsfmt files
* run prettier snapshot tests
Sosuke Suzuki