* Support JavaScript code blocks set apart by triple backticks (``` ... ```)
* Add test for escaped backticks
* Remove TODOs for things we’re never going to support
* Convert escaped backticks to backticks; update tests
* Block inline JavaScript can end with an escaped backtick character
* Updated JavaScript token regexes per @lydell
* In JavaScript blocks, escape backslashes when they immediately precede backticks; additional tests
* Test that we don’t break backslash escaping in JavaScript literals
* Add initial support for template literals with no
interpolation
* Change ‘unexpected string’ error message tests to
use number not identifier prefix.
Identifer prefixes are now valid as tagged
template literals
* Test tagged template literals for non-interpolated
strings and tag function.
* Tagged template literals work for pure Strings.
Pull tagged template definition up to Invocation
level in grammar, enabling chained invocation calls.
We can view a tagged template is a special form
of function call.
* Readying for StringWithInterpolations work.
* Tweaks.
* Fix style
* Pass StringWithInterpolations parameter straight
into Call constructor.
StringWithInterpolations will be output as
template literal, so already in correct form for
outputting tagged template literal.
* Strip down compileNode for StringWithInterpolations
* Done StringLiteral case for interpolated Strings
* Remove need for TemplateLiteral
* Simplify code.
* Small code tidy
* Interpolated strings now outputting as template literals.
Still needs comprehensive testing.
* Move error message tests into error_messages.coffee; remove test that is testing for a Node runtime error
* Split up tests that were testing multiple things per test, so that each test tests only one thing
* Edge cases: tagged template literals containing interpolated strings or even internal tagged template literals
* Make more concise, more idiomatic style
* Pull back extreme indentation
* Restore and fix commented-out tests
* Edge case: tagged template literal with empty string
* Only use new ES2015 interpolated string syntax if we’re inside a tagged template literal; this keeps this PR safe to merge into CoffeeScript 1.x. Remove the code from this commit to make all interpolated strings use ES2015 syntax, for CoffeeScript 2.
* Compiler now _doesn’t_ use template literals.
* Expand tagged template literal tests
* Move ‘Unexpected string’ error message tests into
tagged template literal section.
‘Unexpected string’ is not reported in these test
scenarios anymore. Instead, we error that the
prefixing literal is not a function.
* Don’t unwrap StringWithInterpolations.
Saw bug with program consisting of “#{2}” not
compiling with template literals. Root cause was
that Block.compileNode was unwrapping interpolated
string and so didn’t use compileNode logic at
StringWithInterpolations level.
* No need to bracket interpolated strings any more.
When interpolated string looks like `hello ${2}`,
no extract brackets are needed, as the `s mark the
beginning and end.
* Show html templating with tagged template literals
* Multiline should match multiline
* Comment out unnecessary `unwrap`, which is only needed for CoffeeScript 2 all-ES2015 syntax output
* Added support for for-from loop, see #3832
* for-from: remove extra newline and add support for ranges
* for-from: tidy up the lexer
* for-from: add support for patterns
* for-from: fix bad alignment
* for-from: add two more tests
* for-from: fix test "for-from loops over generators"
See explanation here: https://github.com/jashkenas/coffeescript/pull/4306#issuecomment-257066877
* for-from: delete leftover console.log
* Refactor the big `if` block in the lexer to be as minimal a change from `master` as we can get away with
* Cleanup to make more idiomatic, remove trailing whitespace, minor performance improvements
* for-from: move code from one file to another
* for-from: clean up whitespace
* for-from: lexer bikeshedding
* Move "own is not supported in for-from loops" test into error_messages.coffee; improve error message so that "own" is underlined
* Revert unnecessary changes, to minimize the lines of code modified by this PR
This is an upstream port of https://github.com/decaffeinate/coffeescript/pull/10
See that PR for links to the issues that this fixes.
Just like OUTDENT and CALL_END tokens, close-curly-brace tokens can be generated
without having a real location, and if that position overlaps with a later
token, it can cause the AST to have bad location data. Just like the other two
token types, we now give `}` tokens the position of the previous real token,
which makes all AST nodes have reasonable locations.
This is an upstream port of https://github.com/decaffeinate/coffeescript/pull/9
The existing logic for computing the end location of a string was to take the
end of the string contents, then add the delimiter length to last_column. For
example, `"""abc"""` would have an end position three characters after the `c`.
However, if a string ended in a newline, then the end location for the string
contents would be one line above the end location for the string, so the proper
fix is to move the end location to the next line, not just to shift it to the
right.
This avoids a bug where the location data would sometimes reference a
non-existent location (one past the end of its line). It fixes the AST location
data, although as far as I know, it never has caused correctness issues in the
CoffeeScript output.
This is an upstream port for the patch https://github.com/decaffeinate/coffeescript/pull/8
See https://github.com/decaffeinate/decaffeinate/issues/291 for the bug that this fixed.
For the most part, CoffeeScript and JavaScript have the same precedence rules,
but in some cases, the intermediate AST format didn't represent the actual
evaluation order. For example, in the expression `a or b and c`, the `and` is
evaluated first, but the parser treated the two operators with equal precedence.
This was still correct end-to-end because CoffeeScript simply emitted the result
without parens, but any intermediate tools using the CoffeeScript parser could
become confused.
Here are the JS operator precedence rules:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence
For the most part, CoffeeScript already follows these. `COMPARE` operators
already behave differently due to chained comparisons, so I think we don't need
to worry about following JS precedence for those. So I think the only case where
it was behaving differently in an important way was for the binary/bitwise
operators that are being changed here.
As part of this change, I also introduced a new token tag, `BIN?`, for the
binary form of the `?` operator.
Fixes https://github.com/decaffeinate/decaffeinate/issues/446
In addition to OUTDENT tokens, CALL_END tokens can also be virtual tokens
without a real location, and sometimes they end up with a location that's
incorrect.
This commit adds another post-processing step after normal lexing that sets the
locationData on all OUTDENT tokens to be at the last character of the previous
token. This does feel like a little bit of a hack. Ideally the location data
would be set correctly in the first place and not in a post-processing step, but
I tried that and some temporary intermediate tokens were causing problems, so I
decided to set the location data once those intermediate tokens were removed.
Also, having this as a separate processing step makes it more robust and
isolated.
This fixes the problem in https://github.com/decaffeinate/decaffeinate/issues/371 .
In that issue, the CoffeeScript tokens had three OUTDENT tokens in a row, and
the last two overlapped with the `]`. Since at least one of those OUTDENT tokens
was considered part of the function body, the function expression had an ending
position just after the end of the `]`.
OUTDENT tokens are sort of a weird case in the lexer anyway, since they often
don't correspond to an actual location in the source code. It seems like the
code in `lexer.coffee` makes an attempt at finding a good place for them, but in
some cases, it has a bad result. This seems hard to avoid in the general case.
For example, in this code:
```coffee
[->
a]
```
There must be an OUTDENT between the `a` and the `]`, but CoffeeScript tokens
have an inclusive start and end, so they must always be at least one character
wide (I think). In this case, the lexer was choosing the `]` as the location,
and the parser ended up generating correct location data, I believe because
it ignores the outermost INDENT and OUTDENT tokens. However, with multiple
OUTDENT tokens in a row, the parser ends up producing location data that is
wrong.
It seems to me like there isn't a solid answer to "what location do OUTDENT
tokens have", since it hasn't mattered much, but for this commit, I'm defining
it: they always have the location of the last character of the previous token.
This should hopefully be fairly safe because tokens are still in the same order
relative to each other. Also, it's worth noting that this makes the start
location for OUTDENT tokens awkward. However, OUTDENT tokens are always used to
mark the end of something, so their `last_line` and `last_column` values are
always what matter when determining AST node bounds, so it is most important for
those to be correct.
`"""` (and `"`) strings are lexed into an array of tokens, consisting of
strings and interpolations. Previously, the minimum indententation
inside `"""` strings was stripped from the beginning of _all_ of those
string tokens. Usually, the indentation is longer than any other
sequence of spaces in a `"""` string, so the problem didn't occur in
most cases. This commit makes sure to only strip indentation after
newlines.
Fixes#4314.
Very large decimal number literals, binary number literals and octal
literals are lexed into an INFINITY token (instead of a NUMBER token)
and compiled into `2e308`. That is is supposed to be the case for very
large hexdecimal dumber literals as well, but previously wasn't.
Before:
$ node -p 'require("./").tokens(`0x${Array(256 + 1).join("f")}`)[0][0]'
NUMBER
After:
$ node -p 'require("./").tokens(`0x${Array(256 + 1).join("f")}`)[0][0]'
INFINITY
This commit also cleans up `numberToken` in lexer.coffee a bit.
`isLiteralArguments` mistakenly looked at `Literal`s instead of
`IdentifierLiteral`s.
This also gets rid of the ugly `.asKey` hack in nodes.coffee.
Fixes#4320.
Before:
```
$ cat tmp.coffee.md
test
a
$ ./bin/coffee tmp.coffee.md
ReferenceError: a is not defined
at Object.<anonymous> (/src/coffee-script/tmp.coffee.md:2:3)
...
```
Note how the line and column numbers (2 and 3, respectively) are not
correct.
After:
```
$ ./bin/coffee tmp.coffee.md
ReferenceError: a is not defined
at Object.<anonymous> (/home/lydell/forks/coffee-script/tmp.coffee.md:3:5)
...
```
Line 3, column 5 is the actual position of the `a` in tmp.coffee.md.
Supersedes and fixes#4204.
This pull request adds support for ES2015 modules, by recognizing `import` and `export` statements. The following syntaxes are supported, based on the MDN [import](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import) and [export](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/export) pages:
```js
import "module-name"
import defaultMember from "module-name"
import * as name from "module-name"
import { } from "module-name"
import { member } from "module-name"
import { member as alias } from "module-name"
import { member1, member2 as alias2, … } from "module-name"
import defaultMember, * as name from "module-name"
import defaultMember, { … } from "module-name"
export default expression
export class name
export { }
export { name }
export { name as exportedName }
export { name as default }
export { name1, name2 as exportedName2, name3 as default, … }
export * from "module-name"
export { … } from "module-name"
```
As a subsitute for ECMAScript’s `export var name = …` and `export function name {}`, CoffeeScript also supports:
```js
export name = …
```
CoffeeScript also supports optional commas within `{ … }`.
This PR converts the supported `import` and `export` statements into ES2015 `import` and `export` statements; it **does not resolve the modules**. So any CoffeeScript with `import` or `export` statements will be output as ES2015, and will need to be transpiled by another tool such as Babel before it can be used in a browser. We will need to add a warning to the documentation explaining this.
This should be fully backwards-compatible, as `import` and `export` were previously reserved keywords. No flags are used.
There are extensive tests included, though because no current JavaScript runtime supports `import` or `export`, the tests compare strings of what the compiled CoffeeScript output is against what the expected ES2015 should be. I also conducted two more elaborate tests:
* I forked the [ember-piqu](https://github.com/pauc/piqu-ember) project, which was an Ember CLI app that used ember-cli-coffeescript and [ember-cli-coffees6](https://github.com/alexspeller/ember-cli-coffees6) (which adds “support” for `import`/`export` by wrapping such statements in backticks before passing the result to the CoffeeScript compiler). I removed `ember-cli-coffees6` and replaced the CoffeeScript compiler used in the build chain with this code, and the app built without errors. [Demo here.](https://github.com/GeoffreyBooth/coffeescript-modules-test-piqu)
* I also forked the [CoffeeScript version of Meteor’s Todos example app](https://github.com/meteor/todos/tree/coffeescript), and replaced all of its `require` statements with the `import` and `export` statements from the original ES2015 version of the app on its `master` branch. I then updated the `coffeescript` Meteor package in the app to use this new code, and again the app builds without errors. [Demo here.](https://github.com/GeoffreyBooth/coffeescript-modules-test-meteor-todos)
The discussion history for this work started [here](https://github.com/jashkenas/coffeescript/pull/4160) and continued [here](https://github.com/GeoffreyBooth/coffeescript/pull/2). @lydell provided guidance, and @JimPanic and @rattrayalex contributed essential code.
In f609036bee, a line was changed from
`if length > 0 then (length - 1) else 0` to `Math.max 0, length - 1`. However,
in some cases, the `length` variable can be `undefined`. The previous code would
correctly compute `lastCharacter` as 0, but the new code would compute it as
`NaN`. This would cause trouble later on: the end location would just be the end
of the current chunk, which would be incorrect.
Here's a specific case where the parser was behaving incorrectly:
```
a {
b: ->
return c d,
if e
f
}
g
```
The OUTDENT tokens after the `f` had an undefined length, so the `NaN` made it
so the end location was at the end of the file. That meant that various nodes in
the AST, like the `return` node, would incorrectly have an end location at the
end of the file.
To fix, I just reverted the change to that particular line.
In for example `for` loops, a variable called `i` is generated (for the
loop index). If that name is unavailable, `j` is used instead, then `k`,
`l`, etc. all the way to `z`. Then, `aa`, `ab`, `ac` etc. are used.
This meant that, eventually, `do` would be used, but that's not a valid
variable name since `do` is a JavaScript keyword.
This logic was also inefficiently implemented. For example, going from
`aa` to `ab` or from `az` to `ba` required lots of loop iterations.
This commit changes the variable naming convention. Now, `i`, `j`, `k`,
etc. to `z` are used like before. Then comes `i1`, `j1`, `k1`, etc. Then
`i2`, `j2`, `k2` and so on. This is simpler, efficient and easier to
understand. `i1` is more obvious to be a loop index than `aa`.
Fixes#4267.
- Inline source maps are now shorter by not using pretty-printed JSON.
- `.register()`ed files are now given more information in their inline source
maps: The name and contents of the source file.
- Some code cleanup.
If you decode the inline source map generated (when using `.register()`) for a
file test.coffee with the contents `console.log "it works!"`, here is the
output:
Before:
{
"version": 3,
"file": "",
"sourceRoot": "",
"sources": [
""
],
"names": [],
"mappings": "AAAA;EAAA,OAAO,CAAC,GAAR,CAAY,eAAZ;AAAA"
}
After:
{"version":3,"file":"","sourceRoot":"","sources":["test.coffee"],"names":[],"mappings":"AAAA;EAAA,OAAO,CAAC,GAAR,CAAY,WAAZ;AAAA","sourcesContent":["console.log \"it works!\"\n"]}
Related: #4214.
- Split out a PROPERTY token from the IDENTIFIER token.
- Split out Property from the Identifier in the grammar.
- Split out PropertyLiteral from IdentifierLiteral.
- Show the same type of error message for compound assignment as for `=`
assignment when the LHS is invalid.
- Show the same type of error message when trying to assign to a CoffeeScript
keyword as when trying to assign to a JavaScript keyword.
- Now longer treat `&& =` as `&&=`. The same goes for `and=`, `||=` and `or=`.
- Unify the error message to: `<optional type> '<value>' can't be assigned`.
Previously, the parser created `Literal` nodes for many things. This resulted in
information loss. Instead of being able to check the node type, we had to use
regexes to tell the different types of `Literal`s apart. That was a bit like
parsing literals twice: Once in the lexer, and once (or more) in the compiler.
It also caused problems, such as `` `this` `` and `this` being indistinguishable
(fixes#2009).
Instead returning `new Literal` in the grammar, subtypes of it are now returned
instead, such as `NumberLiteral`, `StringLiteral` and `IdentifierLiteral`. `new
Literal` by itself is only used to represent code chunks that fit no category.
(While mentioning `NumberLiteral`, there's also `InfinityLiteral` now, which is
a subtype of `NumberLiteral`.)
`StringWithInterpolations` has been added as a subtype of `Parens`, and
`RegexWithInterpolations` as a subtype of `Call`. This makes it easier for other
programs to make use of CoffeeScript's "AST" (nodes). For example, it is now
possible to distinguish between `"a #{b} c"` and `"a " + b + " c"`. Fixes#4192.
`SuperCall` has been added as a subtype of `Call`.
Note, though, that some information is still lost, especially in the lexer. For
example, there is no way to distinguish a heredoc from a regular string, or a
heregex without interpolations from a regular regex. Binary and octal number
literals are indistinguishable from hexadecimal literals.
After the new subtypes were added, they were taken advantage of, removing most
regexes in nodes.coffee. `SIMPLENUM` (which matches non-hex integers) had to be
kept, though, because such numbers need special handling in JavaScript (for
example in `1..toString()`).
An especially nice hack to get rid of was using `new String()` for the token
value for reserved identifiers (to be able to set a property on them which could
survive through the parser). Now it's a good old regular string.
In range literals, slices, splices and for loop steps when number literals
are involved, CoffeeScript can do some optimizations, such as precomputing the
value of, say, `5 - 3` (outputting `2` instead of `5 - 3` literally). As a side
bonus, this now also works with hexadecimal number literals, such as `0x02`.
Finally, this also improves the output of `coffee --nodes`:
# Before:
$ bin/coffee -ne 'while true
"#{a}"
break'
Block
While
Value
Bool
Block
Value
Parens
Block
Op +
Value """"
Value
Parens
Block
Value "a" "break"
# After:
$ bin/coffee -ne 'while true
"#{a}"
break'
Block
While
Value BooleanLiteral: true
Block
Value
StringWithInterpolations
Block
Op +
Value StringLiteral: ""
Value
Parens
Block
Value IdentifierLiteral: a
StatementLiteral: break
Commit 347a6255 is a bit problematic:
- It doesn't include the built .js files.
- It breaks `CoffeeScript.register()`. This can be seen by running the tests;
four of them fails. The error is that `CoffeeScript.register()` calls
`CoffeeScript._compileFile()` with the `sourceMap` option enabled, which
returns an object while the code expected a string.
This commit fixes the broken `CoffeeScript.register()`, by setting the
`sourceMap` option to `false` (but still keeping the `inlineMap` option enabled,
which was the intention of commit 347a6255). It also commits the built .js
files. The tests now pass.
`({a = 1}) ->` and `({a: b}) ->` worked, but not the combination of the two:
`({a: b = 1}) ->`. That destrucuring worked for normal assignments, though:
`{a: b = 1} = c`. This commit fixes the param case.
This breaks compatibility with
->
yield for i in [1..3]
i * 2
and
->
yield
i * 2
yield's behaviour now mirrors that of return in that it can be used stand alone as well as with expressions. Thus, it currently also inherits the above limitations.
