Support nohoist feature

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Sub Packages is a common concept in most Mini Program platforms to improve load performance and code
structure. It can be regarded as chunk split in Web development.

Here are some useful links to their official documents.

• WeChat sub packages

• QQ sub packages

• Alipay sub packages

• Baidu sub packages

• Toutiao sub packages

Problems

The original design of sub packages based code splitting result in several limitations. A sub
package cannot require any module in the main package nor other sub packages.

Developers have to place shared code in main package manually, otherwise they will get a compile
error from the Mini Program dev tool. In another hand, if a module was only required by a sub
package, developers should move it into the sub package to reduce size of main package.

Hoist and nohoist

In GojiJS, we use Webpack to analyze module dependencies and bundle the
code. With code splitting we are able to import
dependents in a sub package from anywhere we want, like the main package, node_modules or even other
sub packages. GojiJS can hoist the shared code into a common chunk file ( usually
_goji_commons.js ) in the main package.

Here is an example that has 5 pages, one is in the main package and others are in 2 sub packages (
packageA and packageB ).

GojiJS hoist modules to root common chunk. By doing this the dependencies can match Mini Program sub
packages' limitations.

nohoist.enable

boolean = true if in production mode, otherwise false.

In above example, redux and date-fns are not shared code so they can be moved into sub packages
to reduce size of main package. We call that optimization nohoist.

You can change nohoist.enable option in goji.config.js to toggle this feature.

nohoist.enable is set to false in development mode to speed up code bundling.

nohoist.maxPackages

number = 1

Some modules, like lodash in the example, are shared only by sub packages. It is possible to
forked them into sub packages. Although the size of total packages increases, it does reduce the
size of main package.

To enable this feature, you can set nohoist.maxPackages to a number N above 1. A module shared
less than or equal N will be forked into packageName/_goji_nohoist_[contenthash].js.

Although the code are duplicated, the runtime closure is still a singleton. For more details see
Independent packages.

Please note this feature may heart user lading time because more duplicated code are generated.
You should only use it if size of main package was exceeded or about to exceed.

nohoist.test

function (module, chunks) => boolean RegRex string

You can use this options to nohoist specific modules.