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Merge branch 'master' into harmony-v3.0.11

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alexlamsl
2017-05-23 22:29:04 +08:00
parent 7bcb442e4c e95052a423
commit 37e549ff4f
11 changed files with 194 additions and 45 deletions
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README.md
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@@ -124,7 +124,7 @@ a double dash to prevent input files being used as option arguments:
`url` If specified, path to the source map to append in
`//# sourceMappingURL`.
--stats Display operations run time on STDERR.
--toplevel Compress and/or mangle variables in toplevel scope.
--toplevel Compress and/or mangle variables in top level scope.
--verbose Print diagnostic messages.
--warn Print warning messages.
--wrap <name> Embed everything in a big function, making the
@@ -199,7 +199,7 @@ Example:
To enable the mangler you need to pass `--mangle` (`-m`). The following
(comma-separated) options are supported:
- `toplevel` — mangle names declared in the toplevel scope (disabled by
- `toplevel` — mangle names declared in the top level scope (disabled by
default).
- `eval` — mangle names visible in scopes where `eval` or `with` are used
@@ -298,9 +298,10 @@ like this:
var UglifyJS = require("uglify-es");
```
There is a single high level minification function, `minify(code, options)`, which will
performs all the steps in a configurable manner.
Example:
There is a single high level function, **`minify(code, options)`**,
which will perform all minification [phases](#minify-options) in a configurable
manner. By default `minify()` will enable the options [`compress`](#compress-options)
and [`mangle`](#mangle-options). Example:
```javascript
var code = "function add(first, second) { return first + second; }";
var result = UglifyJS.minify(code);
@@ -308,14 +309,17 @@ console.log(result.error); // runtime error, or `undefined` if no error
console.log(result.code); // minified output: function add(n,d){return n+d}
```
You can also compress multiple files:
You can `minify` more than one JavaScript file at a time by using an object
for the first argument where the keys are file names and the values are source
code:
```javascript
var code = {
"file1.js": "function add(first, second) { return first + second; }",
"file2.js": "console.log(add(1 + 2, 3 + 4));"
};
var result = UglifyJS.minify(code);
console.log(result.code); // function add(d,n){return d+n}console.log(add(3,7));
console.log(result.code);
// function add(d,n){return d+n}console.log(add(3,7));
```
The `toplevel` option:
@@ -326,7 +330,33 @@ var code = {
};
var options = { toplevel: true };
var result = UglifyJS.minify(code, options);
console.log(result.code); // console.log(function(n,o){return n+o}(3,7));
console.log(result.code);
// console.log(function(n,o){return n+o}(3,7));
```
An example of a combination of `minify()` options:
```javascript
var code = {
"file1.js": "function add(first, second) { return first + second; }",
"file2.js": "console.log(add(1 + 2, 3 + 4));"
};
var options = {
toplevel: true,
compress: {
global_defs: {
"@console.log": "alert"
},
passes: 2
},
output: {
beautify: false,
preamble: "/* uglified */"
}
};
var result = UglifyJS.minify(code, options);
console.log(result.code);
// /* uglified */
// alert(10);"
```
To produce warnings:
@@ -345,7 +375,7 @@ var result = UglifyJS.minify({"foo.js" : "if (0) else console.log(1);"});
console.log(JSON.stringify(result.error));
// {"message":"Unexpected token: keyword (else)","filename":"foo.js","line":1,"col":7,"pos":7}
```
Note: unlike `uglify-js@2.x`, the `3.x` API does not throw errors. To
Note: unlike `uglify-js@2.x`, the `3.x` API does not throw errors. To
achieve a similar effect one could do the following:
```javascript
var result = UglifyJS.minify(code, options);
@@ -354,7 +384,7 @@ if (result.error) throw result.error;
## Minify options
- `warnings` (default `false`) — pass `true` to return compressor warnings
- `warnings` (default `false`) — pass `true` to return compressor warnings
in `result.warnings`. Use the value `"verbose"` for more detailed warnings.
- `parse` (default `{}`) — pass an object if you wish to specify some
@@ -518,7 +548,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
assignments do not count as references unless set to `"keep_assign"`)
- `toplevel` -- drop unreferenced functions (`"funcs"`) and/or variables (`"vars"`)
in the toplevel scope (`false` by default, `true` to drop both unreferenced
in the top level scope (`false` by default, `true` to drop both unreferenced
functions and variables)
- `top_retain` -- prevent specific toplevel functions and variables from `unused`
@@ -536,7 +566,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
- `cascade` -- small optimization for sequences, transform `x, x` into `x`
and `x = something(), x` into `x = something()`
- `collapse_vars` -- Collapse single-use non-constant variables - side
- `collapse_vars` -- Collapse single-use non-constant variables - side
effects permitting.
- `reduce_vars` -- Improve optimization on variables assigned with and
@@ -598,7 +628,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
- `reserved` - pass an array of identifiers that should be excluded from mangling
- `toplevel` — mangle names declared in the toplevel scope (disabled by
- `toplevel` — mangle names declared in the top level scope (disabled by
default).
- `eval` — mangle names visible in scopes where eval or with are used
@@ -783,7 +813,7 @@ You can also use conditional compilation via the programmatic API. With the diff
property name is `global_defs` and is a compressor property:
```javascript
var result = uglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
var result = UglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
compress: {
dead_code: true,
global_defs: {
@@ -793,6 +823,32 @@ var result = uglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
});
```
To replace an identifier with an arbitrary non-constant expression it is
necessary to prefix the `global_defs` key with `"@"` to instruct UglifyJS
to parse the value as an expression:
```javascript
UglifyJS.minify("alert('hello');", {
compress: {
global_defs: {
"@alert": "console.log"
}
}
}).code;
// returns: 'console.log("hello");'
```
Otherwise it would be replaced as string literal:
```javascript
UglifyJS.minify("alert('hello');", {
compress: {
global_defs: {
"alert": "console.log"
}
}
}).code;
// returns: '"console.log"("hello");'
```
### Using native Uglify AST with `minify()`
```javascript
// example: parse only, produce native Uglify AST