In 1.3.0, we shipped a change that makes template literal always inlined as single arguments of a function. The problem with template literals is that they whitespace is significant so we can't change it. There are two cases:
```js
call(`
template
template
`);
```
and
```js
call(
`template
template`
);
```
If you always make the same decision to inline, you're going to be wrong for the other use case. The solution that I found that works is to figure out if there's a `\n` before the backtick `` ` ``. If that's the case, then don't inline, otherwise do. We're trying to avoid looking at the source as much as possible but this is one example where we actually don't have a choice if we want to keep the output sane.
1.3.0 made the jest codebase significantly worse because of this. The issue is that once things have been moved, this heuristic won't be able to undo it. So people need to have this fix applied before they run 1.3.0, otherwise it's going to damage their codebase unless they manually change everything back, which is a pain. So I'm going to land this as a hotfix in 1.3.1.
Fixes#1492
* Make slice simpler.
* Drop htmlEscapeInsideAngleBracket function.
Use child.extra.raw (Babylon) and child.raw (Flow) to get the value instead.
* Remove unused htmlEscapeInsideAngleBracket function.
* Update test cases accordingly.
* Fix merge conflict.
* Update tests via `npm test -- -u`.
* Fix multiple consecutive spaces preservation in printJSXChildren.
* Update tests accordingly.
* fix(typescript): fix handling of new keyword
* fix(typescript): fix handling of call signatures
* feat(typescript): share type parameter formatting with flow
* feat(typescript): #1480: implement *Keyword, namespace function and class heritage
* feat(typescript): add type params and modifiers to interfaces
* chore(style): add squigly wings to if/else blocks
* fix(typescript): remove hardline before declare
We never want to break on those at it looks very weird. The reason why I didn't add this yet is because whenever it triggered in the past, the root cause was something else and it helped identify things to fix. But now the remaining ones I'm seeing are no longer underlying issues and they're just about this breaking unnecessarily, so we should just fix it.
This was added in order to follow some eslint rule but it's only confusing when it doesn't break, when it breaks the indentation makes it clear what is happening and you don't need parenthesis.
Fixes#1379
All of the discussions around ternaries are for the form
```js
cond1 ? elem1_if : cond2 ? elem2_if : elem_else
```
but some of them are for the form
```js
cond1 ? cond2 ? elem2_if : elem2_else : elem1_else
```
which is more rare and would be good to call out by adding parenthesis.
```js
cond1 ? (cond2 ? elem2_if : elem2_else) : elem1_else
```
Note that we only want parenthesis if it's written inline, otherwise the indentation is good enough to understand the flow:
```js
cond1
? cond2 ? elem2_if : elem2_else
: elem1_else
```
Right now, expressions inside of template literals are have the level of indentation of the start of the template literal. But oftentimes, expressions are nested inside of template literals and therefore the expression should have this level of nesting.
The heuristic i'm using to decide when to use the template literal nesting is if it's not the first line and if there isn't another expression before on the same line.
* Add eslint as dev dep, reorder scripts.
* Add tests & docs to eslintignore.
* Add eslintcache to gitignore.
* Update yarn lock file 😽.
* Add linting step in the test pipeline.
* Add a set of really basic rules for linting.
* Fix linting 🚀.
* No need for .jsx files to be linted...
* Reorder rules alphabetically.
* Refine rules: drop styling ones, only keep what provides dead code elimination.
* Add no-console rule to be consistent along with the no-debugger one.
* Remove empty line.
* Add eslint-disable-next-line no-console where console log/warn/error are allowed.
* Drop no-console rule.
* Remove eslint-disable-next-line no-console comments.
* Remove linting step in Travis CI.
* Fix linting after merging current master.
* Run `npm test -- -u` after noticing one test was out of sync.
* Drop eslint references from previous implementation.
* Revert yarn lock file.
* Revert scripts ordering.
* Fix incorrect yarn lock file.
In #1251, we now have a proper whitelist of all the types that should have parenthesis. Turns out, it included NullableTypeAnnotation which is `?a`. For `?a => void` this wasn't needed but for `(?(a => b)) => c` it was! It's better to always put it anyway if it's not just a simple literal.
I've added tests for all the combinations I could think of, so we'll catch regressions if they happen.
Fixes#1353
We've had this issue since the beginning and I tagged it as 1.0 but haven't managed to fix it by then. We shouldn't allow things to break in the argument list if we are in the last argument expansion mode. It turns out that we now have all the building blocks needed to fix this:
- have a special way to flag when we are printing the last argument expansion in the code that prints the argument list
- have a way to remove all the softlines from the argument list
Fixes#1301
This is the second part of the fix for the performance regression seen in #1250. In #1217, for correctness reasons, we're now traversing all the conditional groups. This means that we're now in O(n^2). But, in practice, many of those groups are === between each others. So we only need to recurse through one of the instances to know if it's going to break.
This makes the first example go from not terminating to being instant. The second one going from not terminating to taking ~1s. We can also make it instant by tweaking the printing phase, but that's for another PR.
The implementation was checking if the comment was inside of the expression range, which seems like a good idea. Unfortunately, the expression range is not what's inside of `${}` but the actual AST node, which incidentally doesn't include comments. So the logic was off and returned `undefined` which threw afterwards.
Another solution is to find the first quasi where start is > comment start. This means that the comment appeared between the quasi before and this one... therefore in the expression before!
The flow parser has issues with unicode where it makes node location invalid, there are likely other places where node locations are off. So instead of throwing with a weird error, let's attach it to the first one if it doesn't work.
Fixes#1293
As I was debugging #1248, I found out that the code to fix was actually making things worse. The other two branches are for decorators and deleting some random value of a function. I ran all the tests and the flow object is actually now preserving empty lines and didn't change anything else.
I'd rather remove all those and if something comes up then fix it properly upstream than having those crutches that we don't know why they exist anymore.
In #1257, I discovered that if there's a `""` doc at the end, it's not going to trim the previous one correctly. It also happens to fix a few existing things.
This one is pretty crazy. In #927, I changed
```js
concat(["(", join(concat([", "]), printed), ")"]),
```
into
```js
concat(["(", join(concat([", "]), printedLastArgExpanded), ")"]),
```
which makes the example in #1203 look ugly. The crazy thing is that `JSON.stringify(printed) === JSON.stringify(printedLastArgExpanded)`. So they are deep equal but not the same object. In a non-mutative world, this should cause any problem, but we actually mutate those to propagate breaks.
In the break propagation, we only looked at the first one in case of a conditional group. But, because the two were the same object then it also applied to the second one and happened to be the correct behavior! When I changed that piece of code to be two distinct objects, it no longer worked by accident and caused a bunch of weird issues where breaks didn't propagate correctly.
The solution for this case is to propagate the breaks on all the conditions. I'm pretty sure that this is the expected behavior, we want to deeply recurse in all of them, we don't propagate it up the boundary anyway.
The other use case for `traverseInDoc()` is `findInDoc()`, right now it searches for the first conditional group but it seems very arbitrary. I changed it to not search on any and none of the tests are failing, so I think it's safe(tm). If it triggers weird behavior, then it'll at least be expected and not randomly explode at us if we move groups around.
I tried to go through all the conditions for `findInDoc()` but it triggers a few failures (the output look bad). I'm not really sure why. https://gist.github.com/vjeux/5fb7566cc3d65974817d512d1ef6abe1Fix#1203
In #847, I used a heuristic to find if the element was going to be expanded. But, it wasn't 100% accurate because we couldn't know in which conditionalGroup we would land. We added a way for the parent to tell that function if we should be in `expandLastArg`. By replacing the condition by this variable, it now fixes the issues!
This is so good that adding the right abstraction fixes problems across the board :)
Fixes#997
It turns out that we can't reliably detect with the ast if a comment is before or after the ). In order to fix this same problem with `if` I added the `getNextNonSpaceNonCommentCharacter` function. We can use the same here to fix the problem.
Fixes#933
* Hug template literals inside of JSXExpressionContainer
We already hug a bunch of things inside of `{}`. It seems that it's a good idea to do it for template literals as well. I don't think I've seen anyone actually indent them.
Fixes#1090
* Inline jsx elements with single template literal expression
If there is a single expression and a single template literal, then a lot of people in the jsx-style world inline it. I've also myself used this for markdown and printed it that way. So we probably should print it that way.
Note that I'm checking for children.length === 1, this means that if there's any whitespace, this is not going to be true and will not enter this case. So it WON'T reformat
```js
<style>
{`
color: red;
`}
</style>
```
into
```js
<style>{`
color: red;
`}</style>
```
which is great. You have to opt-in to the second style in order to get it.
Fixes#1090
I'm unclear whether anyone was ever confused by this but the eslint page is kind of compelling
```js
// The intent is not clear
var x = a => 1 ? 2 : 3;
// Did the author mean this
var x = function (a) { return 1 ? 2 : 3 };
// Or this
var x = a <= 1 ? 2 : 3;
```
Adding a parenthesis makes it valid with `{"allowParens": true}` rule. Note that if this option is not enabled, the code would not pass lint in the first place.
I've tried a lot of places where to fix this and this is the only one that gives correct results. This is likely not exhaustive but works for that use case. It's been reported twice in issues and I've seen it happen a few other times so we probably want to get it fixed.
Fixes#922Fixes#797
This one sucks.
The range of the `test` of `if (a /* comment */) {}` is only `a` and doesn't include the comment nor parenthesis. This means that we have no way to know if the comment is placed before or after the `)` unless you look at the actual source and strip all the whitespace/comments characters to see if it's a `)`...
This happened on the babel source code twice and many times in the fb codebase. I think we need to fix it unfortunately :(
Fixes#867
We need to call the `skipToLineEnd` which skips `,` after an inline comment. So we have to put it inside of the while loop as you can have many comments, a comma and then many more comments.
Fixes#964
.#1136 accidentally removed all the empty lines between statements inside of switch cases. I just brough back the logic and made sure to only use it for everything but the last line.
* Add exceptions for html escape usage in href and src attributes.
* Add new test cases.
* Remove useless spaces.
* Do not escape if the parser does not do so.
* Implement a different heuristic for keeping along with the parser.
* Update tests.
* Forgot passing options as param.
* Experimental alternative implementation.
* Remove other function.
* Push test after merge.
* Update getJsXRawValue in order to return the unprocessed raw value.
Latest Babylon version includes a fix that allow us to directly
inject the unprocessed raw value available in the `extra.rawValue`
property of the node. A last transformation is applied by replacing
double quotes to `"` entities.
* Drop unused htmlEscapeInsideDoubleQuote function.
* Move getJSXRawValue function logic to the its only call, drop it.
A simple check is performed to determine if the parser is babylon or
flow via `n.value.extra`. Thus, the corresponding raw value is
extracted. If we are converting a string from single quotes to
double quotes, we need to make sure that double quotes are converted
to ".
* Remove ambiguous comment.
* Add Babylon parser.
* Update test cases accordingly, revert regression introduced previously.
* Extract custom tests from tests/flow/
Approach:
1. Remove all .js files in tests/flow except .snap.js files.
2. Copy over all .js files from tests/ in the flow repo.
3. Go through the diff looking for deletions.
- It was easy to see which deletions were due to changes in the tests
due to updates in the flow repo.
- For the rest of the deletions, I used `git blame` to verify that
they had been added by us since the flow tests were copied over.
This makes tests/flow/ simply a copy of the tests from the flow repo,
making it easier to sync with the upstream flow tests in the future.
* Add a script for syncing the flow tests
* Sync the flow tests
We break on `class` before `extends` but didn't for `interface`. Now we do in the same way. Also TIL that `interface` was an actual keyword in JavaScript :P
* Verify parsers against same snapshot
- Reworked run_spec, now accepts 3th optional array argument for
additional parsers to verify against
- Merged duplicate run_spec configs
- Removed duplicate snapshot data
* Formatted run_spec.js with prettier
* Fixed node4 incompatibility
If you write your code in a functional way where you have an arrow function for each argument, it looks better for them to be inline. I can't imagine any case where it would be used in a different way if we limit to a single argument.
Fixes#1065
We started using the same logic for union and intersection but then added a special case for `a & {}`. It turns out that they should be handled completely differently in practice.
The heuristic i'm using is if you go from object to non-object or vis-versa, then inline, otherwise go to the next line and indent (like &&).
Fixes#864Fixes#1017
This is very common for stateful react functional components. It also matches last object expansion. I think that we should only do that for a single argument in function definitions though, unlike the last for function calls.
Fixes#1019
* 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
Right now it's only doing one test for begin/end, but in the issue #1037, we have two nodes that have the same start but different end. The current implementation incorrectly sorts them and the identifier ends up being before the container and therefore the comment search doesn't recurse into it.
Fixes#1037
ast-types was missing a type, I sent a PR on ast-type ( https://github.com/benjamn/ast-types/pull/211 ) which was merged and released (thanks @benjamn for being super quick!). So I'm upgrading ast-types and add the test in this PR.
Fixes#1007
While looking at an instability on the React codebase ( ba1299acc2 (diff-2550aa3d377452ae29361f5e53c51c10) ), I realized that we don't let them break which makes the code look weird.
So I added the ability for them to break :)
We already had a special case for it for a group of 2 elements but now that we are also going in this codepath for 3 if we merge, then we need to do the same here.
Fixes#930
* Add some typescript tests
* fix: Remove extraneous colon in type parameter constraint
* style: Add missing newline at EOF in TS tests
* feat: Pretty print typescript object type annotations
* feat: Pretty print TSFunctionType
* fix: Type annotations was missing on class properties
* Add a new batch of tests
* Bump typescript-eslint-parser
* Add a new batch of tests and fix a syntax error in previous
* Bump typescript-eslint-parser
* Group first arg for inline functions
* Group first arg. Unless there are comments.
* Group first arg. Allow second arg to be empty object/array.
This implementation has a side effect of disallowing empty objects/arrays in the should group last arg heuristic.
* Add handleImportDeclarationComments function.
* Fix indent.
* Update test cases accordingly.
* Implement better heuristic for adding comments.
* Make the test case more exhaustive.
* Refactor condition in printStatementSequence, add new helper function.
* Add new test cases.
* Move logic in SwitchCase case.
* Revert unrelated changes, remove unecessary variables.
* Use util.getLast helper function.
* Move variables out of the loop.
* Simplify code.
* Fix mapping with mutated path.
* Implement checking for not printing the parens in this case.
* Add test case.
* Remove parent type checking.
* Fix test accordingly.
* Refactor to a better heuristic.
* Add new test cases.
* Fix implementation.
* Fix unnecessary function call.
* Add new test cases 🚀.
* Use isObjectTypePropertyAFunction and create isTypeAnnotationAFunction.
* Add missing space.
* Add new test cases.
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
This was intended for object expressions. I tried to remove it for ObjectTypeAnnotation but it changes a ton of stuff as it's used all over the place in many different contexts. We should clean it up but in a later PR :)
Fixes part of #975
In practice, trying to allow calls to be inlined is causing a lot of code to look very weird and unstable as seen by the four issues this is fixing. It also requires us to add a conditional group and do hackery around it.
Fixes#959Fixes#760Fixes#615Fixes#625
* WIP immediate feedback
* typescript parser is drop-in replacement for flow parser
* Add new TypeScript Parser snapshots where drop-in replacement possible
* Snapshot updates after rebasing
* Remove unnecessary stripping of properties on TypeScript parser AST
* Remove annotated issues
* Move TS dependencies to dev for now
* Implement new logic for wrapping binary op in arrowFunctionExpression.
* Add new test cases.
* Reuse new helper function in order to fix#917.
* Add new test case.
* Extend heuristic to dive deeper into mixed types.
* Add new test.
* Enhance logic to cover more cases.
* Add new test cases.
* Disable Flow as it gets BindExpression as an unexpected token.
* Simplify getCombinedDeepest function.
* Add missing case.
* Extract all conditions in switch cases to one top level condition.
* Refactor implementation to make it cleaner and also handle ExpressionStatement.
* Update related test cases.
* Add new test case.
* Make condition less expensive.
* Clean up unecessary conditions, simplify condition involving startsWithOpenCurlyBrace.
* Update and add new test cases for better coverage.
* Remove unecessary condition, refactor canBeFirstInStatement to drop some useless parens.
* Update test cases accordingly 🚀.
* Add new handleOnlyComments function.
* Update tests.
* Update test as the printer forces a trailing newline if there were any contents.
* Implement a different heuristic.
* Update tests.
* Add directives checking in handleOnlyComments function.
* Add directives checking in handleOnlyComments function (amend to retrigger CI).
* Remove duplicate.
* Add new helper function to convert comments as blocks in ExportNamedDeclaration.
* Add new test.
* Switch to a leading position.
* Update test accordingly.
The comments infra has been architected with trailing operators and fails for leading `|`. Instead of having leading comments, we can put trailing comments on the previous one and use the same technique as assignment to deal with the indentation.
Fixes#849
This happens very frequently that naming a test makes the entire line go > 80 columns and requires to indent everything which takes a lot more space. We've had this being reported multiple times and it also affects a lot of tests inside of fb.
Fixes#159
(Note, this is built on-top of #841 but github doesn't handle stacked pull requests well...)
This is a leftover from the recast prototype, it hasn't been touched since then. I have never seen anyone not put the label on the same line.
Fixes#859
This is a neat trick from the React codebase. It helps highlight the fact that this is an assignment and not a comparison which is subtle to realize.
Fixes#861
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 turns out that my fix was not correct. We should not add parenthesis for FunctionDeclaration instead of checking if the function expression is named.
Fixes#819
In #596, I fixed a bunch of jsx expression comment edge cases and happened to add a softline there. But it turns out that it's not needed and is actually harmful :)
Fixes#712
Since this is extremely rare, I just took the easy way out and if you are adding a comment inside the "as" node, I just move it outside. We could be more fancy but that works.
Fixes#620
This has come up a couple times on the issue tracker on the react-native-web discussion about Twitter internals. It seems like there's a concensus that people don't break long require calls and they'd rather have it go > 80 columns.
Fixes#303Fixes#752
I'm not really sure what a general rule is for those, but starting with LogicalExpressions should be good. Outside of identifiers, function calls and logical expressions, there aren't a lot of things you'd put there in real code anyway.
Fixes#822
Instead of trying to figure out a complicated way to preserve their correct position, it's easier to just migrate those comments before the class.
Fixes#693Fixes#694
Printing a merged group indented was actually not the right fix. The right fix was to print them in a single line. It used to have this behavior when I was mutating the first group but now that I don't anymore I need to reproduce this condition.
Fixes#823
We need to add parenthesis around function expressions if they are named otherwise the name leak, but if the function is not named then it's just superfluous.
The conditional change is due to a bad use of switch case where it would fall through the next one. We don't want parenthesis there.
* Add new handleFunctionDeclarationComments function.
* Add dangling comments printing for function params.
* Add new test case.
* Update tests.
* Refactor handleFunctionDeclarationComments to only addDanglingComment when no params.
* Remove unecessary helper function, only attach dangling comments when no params.
* Reset flow tests, no more regression.
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
The idea is that if you reach the end of the `}` inside of a template literal, we have to flush the trailing comma, otherwise it would generate invalid code. We also need the same special case for JSX.
I don't like adding yet another type of document but it seems like the most elegant way to solve the problem.
Fixes#623
* Add handleTemplateLiteralComment helper function.
* Fix handleTemplateLiteralComment function.
* Extend handleTemplateLiteralComment to deal with trailing comments 🚀.
* Add test.
* Make handle comments function naming more consistent, fix merge conflicts.
* Update tests.
* Add better comment injection in Template Literal.
* Pass options to attach function.
* Update tests to match new implementation.
* Fix let -> var in findExpressionIndexForComment for NodeJS v4.
* Reorder after merge conflicts.
* Drop old tests for dangling arrays.
* Replace redundant conditional by a boolean 🚀.
* Refactor implementation.
I originally wanted to expand it but I think that it may not be a good decision because it's very common for them to be empty and you want it to take as little space as possible.
I tried to remove all those conditions but I think that there are valid places where we always want to expand like empty if/for/while loops.
Fixes#778
In addition to Observable, $ or _, we should also add `this` to the list of things that are likely factory and not objects you want to apply things on directly.
I added a way to make the function call break on its own line when it doesn't fit in one line and indent. But I think that only having the indentation is enough, having the call on its own line feels weird.
Fixes#777
Previously we would blindly put leading comments of the next expression, but we didn't account for a real trailing comment. By checking if the leadingNode is on the same line, we can correctly put it there when needed
Fixes#685
* Add handleAssignmentPatternComments helper function.
* Add new tests 🎉.
* Remove unecessary arg in function.
* Reorder it.
* Experimental fix for key comments in the printComments function.
* Pull master and switch to @vjeux implementation.
* Fix bad rebase.
* Add additional checking for enclosingNode in handleObjectProperty function.
There is an off by one error which made the algorithm not work all the time. In many cases, it actually is the opposite, so whenever you save, it adds/removes that line. I noticed it during the --debug-check run on our codebase but didn't investigate.
Fixes#723
This has come up many times in the past and while going through the fb codebase, there are a few instances where we group array elements logically using empty lines and it's a shame that they are gone.
I've started the discussion around it but I think that it was a mistake. It feels weird to add parenthesis on object values sometimes but not others. I think that it's best to let prettier do its work on staying under 80 columns based on the rules we added.
We inline function definitions but we shouldn't inline new expressions,
835befebf5 introduced both call expressions and new expressions. Call expressions have been removed but looks like new haven't.
This was surprisingly easy to write!
Technically, it doesn't ignore the next line but the next expression or block but I'm guessing that people are already used to `// eslint-disable-next-line` so it's going to be an easier learning curve.
Fixes#120
* Extend ReturnStatement case to better handle comments in argument 🎉.
* Update test.
* Add missing space between return and left parenthese.
* Fix current tests and add new tests.
* Do not break one-liner returns.
* Revert specific test.
* Patch from #683.
In #563 it looked odd that there was no space before `//`, it turns out that we don't automatically go to the new line for dangling comments. I think that we just should no matter what, so this is what this diff does.
Fixes#563
* Inject source text into printAstToDoc function.
* Add getNodeSource helper function.
* Fix Flow drawback with missing DeclareTypeAlias by checking the node source.
* Add new test.
* Fix getNodeSource helper function.
* Revert text injection.
* Refactor DeclareTypeAlias printing.
* Drop expensive getNodeSource helper function 🗑️.
* Refactor declareTypeAlias case in printer.
* Update tests.
* Implement the same logic for DeclareInterface.
* Update the tests.
* Fix missing semicolons and typo.
* Put Flow specific node detection code into own helper function 🚀.
* Refactor isFlowNodeStartingWithDeclare helper function.
* Simplify isFlowNodeStartingWithDeclare helper function.
* Rename test spec.
* Update tests.
When there is a comment right before the first `.`, we want to force break such that the comment is printed on its own line.
Note: this needs to be based on-top of #667 as it always indent the first `.`
Fixes#613
* Add prettier indentation for UnionTypeAnnotation in ObjectTypeAnnotation.
* Update tests accordingly.
* Fix indentation.
* Update a bunch of tests 🚀.
* Switch to a more consistent indentation.
* Fix tests to match new indentation 🚀.
The reason why trailing comments on a line work with commas is because of a special `lineSuffix` document that delays printing the content until a \n is printed. But `lineSuffix` only worked for pure string. By making it work with arbitrary documents we can fix trailing commas with trailing comments.
Fixes#538
Before, we would always concatenate the first `.call()` if the identifier started with a capital letter, but we do want to break if the content of the call doesn't fit in one line.
Fixes#639
Because the group was too high up, the comment would be taken into consideration to determine the size and it would break and add parenthesis. Adding a group where we actually want the ifBreak seems to be passing all the existing tests and fixes this edge case.
Fixes#655
We already preserve blank lines inside of classes but not objects. It's still very common to have objects that represent classes (React.createClass) and having the same behavior there seems like a good idea. It does make the snapshot tests look better!
Fixes#554
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
* Do not indent binary expressions inside of if
The reason why the indent has been added is to support the
```js
var x = a ||
b;
```
use case where we need a level of indentation. But inside of a `if` it just looks strange
```js
if (
a ||
b
) {
```
because the parent already indented the first line.
Fixes#567
* Tweak logic to make more explicit
We want to preserve an empty line before the last comment. It is added as a trailing comment of the node and adding the same logic to detect if the next line is empty is working.
Fixes#566
* Remove last trailing line for directives-only files
There are two hardlines that are added that do not need to.
- The first one is when there's an empty line afterwards, we want to remove it. The solution I opted for to fix this one is to trimRight the originalText so that globally it's never going to return yes for the isNextLineEmpty.
- The second one is at the end of Program, but we already printed it inside of the directive itself, so we can just add a condition to make sure it's only printed when there's a body or a comment, but not a directive.
Fixes#527
* Add comment
If you removed it before #561, it would trigger an exception in the globalPreceding branch. But now that we don't have this hack anymore, it works fine.
Fixes#543
Babylon has a two top level nodes: File and Program whereas flow just has Program. This causes two things two happen that prevents comments from being displayed:
1) Because there's a single node, none of following/preceding/enclosing exist. We ran into a TOOD case that we now need to fill. We just need to attach comments to the only node we have: the ast.
2) Both the raw comments and the computed comments are set on the `.comments` field of the object, however, it is being reset after calling `attach`, so we lose the computed comments :( The fix is to use a local variable and delete the comments before calling `attach`.
Since we don't print EmptyStatement, we don't want to attach comments to them. I've tried actually printing the EmptyStatement but it messes up a ton of other things.
I made sure that MemberExpressions where printed correctly but didn't do the same for CallExpression. Now it is! It is a bit less straightforward because the comments for the root CallExpression have already been printed, so we need to extract the first call out.
(This is the last place where we drop comments on the test suite, we can start enabling throwing when comments are dropped!)
* Add parentheses if node is StringLiteral surrounded by ExpressionStatement :tools:.
* Add new test.
* Update tests to run against Babylon, plus no regression case.
* Split actual test and no regression test in two files.
* Disable Flow till facebook/flow#3234 is merged.
The original motivation for this change is trying to fix#560 where the comment was attached to the JSXText node instead of the JSXExpressionContainer because it used the globalPrecedingNode. In general, I don't think that it is very safe to attach a comment to a random node just because it happened to be before.
I tried to delete the globalPrecedingNode codepath and I think that it actually improves the results. I'll add inline comments in the pull request to explain the various changes.
Fixes#560
This reverts commit 7148184d65.
There are four types of literals where escapes were normalized:
1. Strings ('\xAb' and "\xAb")
2. Regexes (/\xAb/)
3. Untagged template literals (`\xAb`)
4. Tagged template literals (tag`\xAb`)
However, changing the case of the escapes alters the runtime behavior of
in two of the above cases.
```js
/\xAb/.source === '\\xAb' // true
String.raw`\xAb` === '\\xAb' // true
```
So for regexes and tagged template literals the escapes must not be
changed. Instead of enforcing lowercase escapes in only 50% of the
different cases, it was decided not to bother with escapes at all.
Closes#562.
While trying to figure out how to handle both MemberExpression comments and IfStatement comments, I ended up doing this one as well... Sorry @yamafaktory :(
The logic is a bit annoying but works.
Fixes#487
There are currently three issues related to suboptimal rendering of MemberExpression chains. The previous implementation was trying to flatten only a single group at the same time, but it didn't work well because we didn't have the full context to be able to make decisions.
In this implementation, I'm going through the entire chain at the same time and group it into logical units and make decisions based on this. It solves all the problems I can think of and if we need to tweak it in the future, it should be easy.
Fixes#268Fixes#212Fixes#21
If there's a break inside of a call, we want to force it in the group, otherwise it may get the indentation wrong. See the real-world use case in #513Fixes#513
It turns that our hasNextLine logic needs to be tuned to skip all the trailing comments. The code is not pretty but it does the job. It looks like it fixes a bunch of things in the test cases :)
I made sure that nested inline comments are NOT valid JavaScript
```js
/* /* a */ */
Uncaught SyntaxError: Unexpected token *
```
so it is okay to do a dumb search for */ when you are in a comment
* Print \x and \u escapes in strings and regexes lowercase
Theoretically, we would want to do this for escapes int identifiers as
well. However, neither flow nor babylon preserves escapes in
identifiers. For example, `\u0061.\u{0061}` cannot be distinguished from
`a.a`. Nobody uses such escapes in real code anyway. It could also be
considered a feature that such escapes are converted to real unicode
characters.
* Update snapshots
* Normalize escapes in template literals
* Update snapshots
* [Failing test] Comments in call expression
```js
foo(
// Hi
)
```
prints
```js
foo
// Hi();
```
* add one more failing case
* Don't group last args that has comments attached
* Update snapshot
It turns out that the range is not inclusive. It incorrectly included a \n after and would expand way more objects than we intended to.
I found it while running prettier on the codebase.
I'll make 0.14.1 for this.
* Print numbers in a uniform way
- Still preserve the radix (binary, octal, hexadecimal or decimal) used
in the original source code.
- Still preserve scientific notation.
- Add 0 to fractions. `.1` -> `0.1`
- Remove trailing dots from integers. `1.` -> `1`
- Always print the radix letters lowercase. `0b`, `0o`, `0x`
- Always print scientific notation lowercase. `1e1`
- Always print hexadecimal digits uppercase. `0x123ABCDEF`
- Remove unneeded plus in scientific notation. `1e+1` -> `1e1`
- Remove unneeded zeroes in scientific notation. `1e-001` -> `1e-1`
- Preserve leading zeroes in non-decimal radix. This can be useful when
working in binary, and having both `0b111000` and `0b000111` for
example.
* Always print numbers lowercase
* Remove trailing dot in scientific notation
* Update snapshots
Another attempt at solving the issue where objects are not expanded the way people expect. If there's any new line in the original source, it's going to expand it. This gives more control to the user in how the objects should be formatted.
Fixes#74
It turns out that in an unlikely turn of event, the inner group can be inline and not print the opening paren but the outer group breaks and outputs the closing paren which generates invalid JavaScript.
I tried removing the group altogether and no tests failed, so I'm assuming the group wasn't needed in the first place. If it was, we should add tests to cover this.
Fixes#501
* Proper support for dangling comments
In one code path, the dangling comment case is not properly handled. So I added the dangling comment, but it turns out that we only print manually in two node types: Program and BlockStatement. I made the generic printComment function print it everywhere but those two nodes. I tried to get rid of those special cases but unfortunately we need them there otherwise they are not printed at the right place.
Fixes#20
* Output dangling comments in specific places
The logic was already working, it was just special-cased to the first comment of the file! Presumably because the new line detection logic used to be broken ;)
I manually checked the first 10 snapshots and they are all legit, so I assume that all of them are.
Fixes#356
We don't call the generic print on the BinaryExpression itself, so we need to manually print those comments. It's going to be useful for my work on the MemberExpression :)
It's actually not needed to use conditionalGroup as we can use ifBreak for it. I was able to do it just for cleanup and found out that it also fixed two of the bugs we have with comments. That's great :p
Fixes#485Fixes#486
Conditionals are very common in JSX and it is unfortunate that they take up so much vertical space in the current prettier.
This pull request does a few tweaks:
- It hugs ConditionalExpression (ternary) and LogicalExpression (&&) inside of `{}` in a jsx child, not an attribute
- It doesn't output parenthesis if your parent is a LogicalExpression (&&)
Fixes#317
Mobx is the only popular JavaScript library that I know about which uses decorators. They put things on the same line so we should follow their conventions.
The logic implemented here is the following: if there is one decorator, it's on the same line. If there is more than one, they are each on their own line.
Fixes#325
This was introduced by #314 where `line` should have been `softline`. By the way, I was going to propose renaming `line` to `line_or_space` and `softline` to `line_or_nothing` which should make it more explicit what is going on.
Fixes#461
* 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
Given the discussion on #296, it seems like there's debate between spaces around `{}` but no one puts spaces around `[]`. So changing the behavior to respect this.
The original intent of it was for `if then else` and `try catch` as they aren't likely to be empty, but it accidentally caught function bodys, which have many valid reasons to be empty. Let's special case those out.
This one is really weird
```js
if (() => {} ? 1 : 0) {}
```
parses fine but
```js
if (() => {
} ? 1 : 0) {}
```
is a syntax error. Let's always add a parenthesis.
Note that no one is every going to write this in practice, this is really useless :p
We actually need this `;` for EmptyStatement, otherwise it applies to the next block of code. (Creating a label with an empty statement is completely useless, but it triggers a lot in the fuzz testing tool)
Fixes#376
Danny Arnold