Minification

Whitespace, identifier and syntax minification, plus property mangling.

Minification is a choice about the bytes a build leaves behind, and a person who has not made it should get output they can still read. All minification is off by default.

The three switches

They are independent, so minifyWhitespace alone is a safe way to shrink a file for debugging while keeping names intact.

Option	What it does
`minifyWhitespace`	Remove insignificant whitespace
`minifyIdentifiers`	Shorten local identifiers
`minifySyntax`	Apply size-reducing rewrites

--minify on the command line is shorthand for all three:

guchho build src/app.js --minify
guchho build src/app.js --minify-whitespace   # only one

Dropping code

drop - drop: ['console', 'debugger'] removes console.* calls and debugger statements.

dropLabels - remove a labelled statement outright, the classic way of fencing off development-only code:

build: { dropLabels: ['DEBUG'], define: { DEBUG: 'false' } }

while (DEBUG) { /* development-only */ }   // the whole loop is removed

Keeping names

keepNames preserves function and class names while minifying, which matters when stack traces or reflection read them.

Property mangling

Option	Meaning
`mangleProps`	Regex matching property names to shorten
`reserveProps`	Regex of names to protect
`mangleQuoted`	Also shorten `obj["name"]` string keys
`mangleCache`	Carry name decisions between builds

mangleCache keeps a project's shortened property names stable across builds, so a hot-reload session does not invalidate cached files. See the CLI reference for the file-backed spelling.

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