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Mihai Bazon
2015-03-29 13:13:40 +03:00
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@@ -52,70 +52,87 @@ a double dash to prevent input files being used as option arguments:
The available options are: The available options are:
``` ```
--source-map Specify an output file where to generate source map. --source-map Specify an output file where to generate source
[string] map.
--source-map-root The path to the original source to be included in the --source-map-root The path to the original source to be included
source map. [string] in the source map.
--source-map-url The path to the source map to be added in //# --source-map-url The path to the source map to be added in //#
sourceMappingURL. Defaults to the value passed with sourceMappingURL. Defaults to the value passed
--source-map. [string] with --source-map.
--source-map-include-sources --source-map-include-sources Pass this flag if you want to include the
Pass this flag if you want to include the content of content of source files in the source map as
source files in the source map as sourcesContent sourcesContent property.
property. [boolean] --in-source-map Input source map, useful if you're compressing
--in-source-map Input source map, useful if you're compressing JS that was JS that was generated from some other original
generated from some other original code. code.
--screw-ie8 Pass this flag if you don't care about full compliance --screw-ie8 Pass this flag if you don't care about full
with Internet Explorer 6-8 quirks (by default UglifyJS compliance with Internet Explorer 6-8 quirks
will try to be IE-proof). [boolean] (by default UglifyJS will try to be IE-proof).
--expr Parse a single expression, rather than a program (for --expr Parse a single expression, rather than a
parsing JSON) [boolean] program (for parsing JSON)
-p, --prefix Skip prefix for original filenames that appear in source -p, --prefix Skip prefix for original filenames that appear
maps. For example -p 3 will drop 3 directories from file in source maps. For example -p 3 will drop 3
names and ensure they are relative paths. You can also directories from file names and ensure they are
specify -p relative, which will make UglifyJS figure out relative paths. You can also specify -p
itself the relative paths between original sources, the relative, which will make UglifyJS figure out
source map and the output file. [string] itself the relative paths between original
-o, --output Output file (default STDOUT). sources, the source map and the output file.
-b, --beautify Beautify output/specify output options. [string] -o, --output Output file (default STDOUT).
-m, --mangle Mangle names/pass mangler options. [string] -b, --beautify Beautify output/specify output options.
-r, --reserved Reserved names to exclude from mangling. -m, --mangle Mangle names/pass mangler options.
-c, --compress Enable compressor/pass compressor options. Pass options -r, --reserved Reserved names to exclude from mangling.
like -c hoist_vars=false,if_return=false. Use -c with no -c, --compress Enable compressor/pass compressor options. Pass
argument to use the default compression options. [string] options like -c
-d, --define Global definitions [string] hoist_vars=false,if_return=false. Use -c with
-e, --enclose Embed everything in a big function, with a configurable no argument to use the default compression
parameter/argument list. [string] options.
--comments Preserve copyright comments in the output. By default this -d, --define Global definitions
works like Google Closure, keeping JSDoc-style comments -e, --enclose Embed everything in a big function, with a
that contain "@license" or "@preserve". You can optionally configurable parameter/argument list.
pass one of the following arguments to this flag: --comments Preserve copyright comments in the output. By
- "all" to keep all comments default this works like Google Closure, keeping
- a valid JS regexp (needs to start with a slash) to keep JSDoc-style comments that contain "@license" or
only comments that match. "@preserve". You can optionally pass one of the
Note that currently not *all* comments can be kept when following arguments to this flag:
compression is on, because of dead code removal or - "all" to keep all comments
cascading statements into sequences. [string] - a valid JS regexp (needs to start with a
--preamble Preamble to prepend to the output. You can use this to slash) to keep only comments that match.
insert a comment, for example for licensing information. Note that currently not *all* comments can be
This will not be parsed, but the source map will adjust kept when compression is on, because of dead
for its presence. code removal or cascading statements into
--stats Display operations run time on STDERR. [boolean] sequences.
--acorn Use Acorn for parsing. [boolean] --preamble Preamble to prepend to the output. You can use
--spidermonkey Assume input files are SpiderMonkey AST format (as JSON). this to insert a comment, for example for
[boolean] licensing information. This will not be
--self Build itself (UglifyJS2) as a library (implies parsed, but the source map will adjust for its
--wrap=UglifyJS --export-all) [boolean] presence.
--wrap Embed everything in a big function, making the “exports” --stats Display operations run time on STDERR.
and “global” variables available. You need to pass an --acorn Use Acorn for parsing.
argument to this option to specify the name that your --spidermonkey Assume input files are SpiderMonkey AST format
module will take when included in, say, a browser. (as JSON).
[string] --self Build itself (UglifyJS2) as a library (implies
--export-all Only used when --wrap, this tells UglifyJS to add code to --wrap=UglifyJS --export-all)
automatically export all globals. [boolean] --wrap Embed everything in a big function, making the
--lint Display some scope warnings [boolean] “exports” and “global” variables available. You
-v, --verbose Verbose [boolean] need to pass an argument to this option to
-V, --version Print version number and exit. [boolean] specify the name that your module will take
when included in, say, a browser.
--export-all Only used when --wrap, this tells UglifyJS to
add code to automatically export all globals.
--lint Display some scope warnings
-v, --verbose Verbose
-V, --version Print version number and exit.
--noerr Don't throw an error for unknown options in -c,
-b or -m.
--bare-returns Allow return outside of functions. Useful when
minifying CommonJS modules.
--keep-fnames Do not mangle/drop function names. Useful for
code relying on Function.prototype.name.
--reserved-file File containing reserved names
--reserve-domprops Make (most?) DOM properties reserved for
--mangle-props
--mangle-props Mangle property names
--name-cache File to hold mangled names mappings
``` ```
Specify `--output` (`-o`) to declare the output file. Otherwise the output Specify `--output` (`-o`) to declare the output file. Otherwise the output
@@ -189,6 +206,69 @@ comma-separated list of names. For example:
to prevent the `require`, `exports` and `$` names from being changed. to prevent the `require`, `exports` and `$` names from being changed.
### Mangling property names (`--mangle-props`)
**Note:** this will probably break your code. Mangling property names is a
separate step, different from variable name mangling. Pass
`--mangle-props`. It will mangle all properties that are seen in some
object literal, or that are assigned to. For example:
```js
var x = {
foo: 1
};
x.bar = 2;
x["baz"] = 3;
x[condition ? "moo" : "boo"] = 4;
console.log(x.something());
```
In the above code, `foo`, `bar`, `baz`, `moo` and `boo` will be replaced
with single characters, while `something()` will be left as is.
In order for this to be of any use, we should avoid mangling standard JS
names. For instance, if your code would contain `x.length = 10`, then
`length` becomes a candidate for mangling and it will be mangled throughout
the code, regardless if it's being used as part of your own objects or
accessing an array's length. To avoid that, you can use `--reserved-file`
to pass a filename that should contain the names to be excluded from
mangling. This file can be used both for excluding variable names and
property names. It could look like this, for example:
```js
{
"vars": [ "define", "require", ... ],
"props": [ "length", "prototype", ... ]
}
```
`--reserved-file` can be an array of file names (either a single
comma-separated argument, or you can pass multiple `--reserved-file`
arguments) — in this case it will exclude names from all those files.
A default exclusion file is provided in `tools/domprops.json` which should
cover most standard JS and DOM properties defined in various browsers. Pass
`--reserve-domprops` to read that in.
When you compress multiple files using this option, in order for them to
work together in the end we need to ensure somehow that one property gets
mangled to the same name in all of them. For this, pass `--name-cache
filename.json` and UglifyJS will maintain these mappings in a file which can
then be reused. It should be initially empty. Example:
```
rm -f /tmp/cache.json # start fresh
uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js
```
Now, `part1.js` and `part2.js` will be consistent with each other in terms
of mangled property names.
Using the name cache is not necessary if you compress all your files in a
single call to UglifyJS.
## Compressor options ## Compressor options
You need to pass `--compress` (`-c`) to enable the compressor. Optionally You need to pass `--compress` (`-c`) to enable the compressor. Optionally