`reduce_vars` enables substitution of variables but did not clone the value's `AST_Node`.
This confuses `collapse_vars` and result in invalid AST and subsequent crash.
fixes#1609
Liberal use of `Compressor.transform()` and `AST_Node.optimize()` presents an issue for look-up operations like `TreeWalker.in_boolean_context()` and `TreeWalker.parent()`.
This is an incremental fix such that `AST_Node.optimize()` would now contain the correct stack information when called correctly.
Self-referenced function has non-fixed values assigned to its parameters.
Let `unused` & `!keep_fnames` do the scanning, then apply `reduce_vars` only to unnamed functions.
fixes#1595
As patched on `harmony`, `statement()` is the only user of `embed_tokens()` with a missing error branch.
Updated test case and match up with `harmony` to facilitate future merging.
- one-use function call => IIFE should take `eval()` & `arguments` into account
- if unused parameter cannot be eliminated, replace it with `0`
fixes#1583
those were not optimised for `unused` before, which made it necessary for `reduce_vars` to have separate steps for `keep_fnames`
docs update by @kzc
closes#1577
Function expression can be assigned to a variable and be given a name. Ensure function name is the reduced variable before clearing it out.
fixes#1573fixes#1575
- omitting trailing semi-colon in do-while breaks non-browser parser, e.g. uglify-js 1.x
- trailing semi-colon only breaks IE8 if followed by `else` or `while`
- always use braces in do-while body to workaround 2nd case with no size loss in compression
fixes#1568
`AST_Label.references` get `.initialize()` to `[]` every time after `.clone()`
So walk down the tree to pick up the cloned `AST_LoopControl` pieces and put it back together.
`unsafe` turns undefined keyword into a variable of the same name if found, but that interferes with other related optimisations.
Keep track of such transformations to ensure zero information loss in the process.
Bookmarklet for instance implicitedly assumes a "completion value" without using `return`.
The `expression` option now supports such use cases.
Optimisations on IIFEs also enhanced.
fixes#354fixes#543fixes#625fixes#628fixes#640closes#1293
Avoid variable substitution in the following cases:
- use of variable before declaration
- declaration within conditional code blocks
- declaration within loop body
fixes#1518fixes#1525
Modules like webpack and grunt-contrib-uglify still uses `ast.transform(compressor)` before `Compressor.compress(ast)` was introduced.
Workaround this compatibility issue by deactivating `reduce_vars` in such case.
Also fix use case with omitted `options` when calling `Compressor()`.
fixes#1516
A function call or IIFE with an immediately preceding comment
containing `@__PURE__` or `#__PURE__` is deemed to be a
side-effect-free pure function call and can potentially be
dropped.
Depends on `side_effects` option.
`[#@]__PURE__` hint will be removed from comment when pure
call is dropped.
fixes#1261closes#1448
- support arrays, objects & AST_Node
- support `"a.b":1` on both cli & API
- emit warning if variable is modified
- override top-level variables
fixes#1416closes#1198closes#1469
previously test cases with the same name would be skipped except for the last one
`test/run-test.js` will now report duplicated names as errors
closes#1461
- remove extra tree scanning phase for `negate_iife`
- `negate_iife` now only deals with the narrowest form, i.e. IIFE sitting directly under `AST_SimpleStatement`
- `booleans`, `conditionals` etc. will now take care the rest via more accurate accounting
- `a(); void b();` => `a(); b();`
fixes#1288closes#1451
- assign statement does not count towards variable usage by default
- only works with assignments on the same scope level as declaration
- can be disabled with `unused` set to "keep_assign"
- `toplevel` to drop unused top-level variables and/or functions
- `top_retain` to whitelist top-level exceptions
closes#1450
- remove call to evaluate() in is_constant() and let nested optimize() does its job instead
- reject RegExp in is_constant() and remove special case logic under collapse_vars
- operands to conditionals optimisation are now always evaluate()-ed
- throw error in constant_value() instead of returning undefined to catch possible bugs, similar to make_node_from_constant()
- optimise binary boolean operators under `evaluate` instead of `conditionals`
If using `inSourceMap` this fix will ensure the copying of `sourcesContent` is based on potentially normalized `sources` values (https://github.com/mozilla/source-map/blob/master/lib/source-map-consumer.js#L304-L309).
For example `normalize` (https://github.com/mozilla/source-map/blob/master/lib/util.js#L80-L123) will rewrite `./dist/mySource.js` to `dist/mySource.js` in the target `_sources` of the `SourceMapConsumer`. As a result `orig_map.sourceContentFor(source, true);` would return `null` since the orginal `source` was no longer available in the consumer. By using the keys generating from the `SourceMapConsumer.constructor` consistency is ensured.
Using the symbol declaration tracking of UglifyJS doesn't make sense here
anyway, `arguments` always comes from something in the current scope.
fixes#1299
Fixes: #1247
Fix --mangle-props and --name-cache inconsistency.
AST_Dot and AST_Sub properties are now mangled by --mangle-props
without regard to being used in an assignment statement.
Note: if --mangle-props is used then *all* javascript files used must
be uglified with the same mangle options.
Fix the ignore_quoted=true mangle option, also known as
`--mangle-props=unquoted`. If a given property is quoted anywhere
it will not be mangled in any quoted or non-quoted context.
* Escaped newlines should also produce SyntaxError
* Fix multiline comment parsing and add tests
* Adapt makePredicate to handle \u2028 and \u2029
* Move up nlb check in regex so it's checked before any escape handling
* Change error messages to conform ecma standard
* Find_eol not recornizing \u2028 and \u2029 as line terminator
* Remove \u180e as it is removed in unicode 6.3.0 from the category zs
catch identifier is mangled correctly for ES5 standards-compliant JS engines by default.
Unconditionally use the ie8 if/do-while workaround whether or not --screw-ie8 is enabled.
To support non-standard ie8 javascript use: uglifyjs --support-ie8
This should simplify and improve implementation, make it easier to
implement template strings, and keep master a bit more in sync with
harmony.
Previous implementation wasn't broken, though the loop gave me the
impression it could read infinite numbers and annoyed me a bit. It was
also slightly unnecessary because the lookup involved only 3 characters.
The option added in fbbaa42ee5 wasn't
being respected inside object literals, so quoted property names would
still be stripped out with this option.
This is mostly a corner-case, but useful when the output is passed to
something like the Closure compiler, where quoted property names can be
used to prevent mangling.
* Don't interpret strings with escaped content as directive
* Don't interpret strings after empty statement as directive
* Adapt output to prevent strings being represent as directive
* Introduce UGLIFY_DEBUG to allow internal testing like EXPECT_DIRECTIVE
