fix(@angular-devkit/build-angular): re-introduce pure_getters

cexbrayat · vikerman · commit fa8216c217bc · 2019-10-03T14:29:24.000-07:00
PR #15607 removed the `_pure_getters` optimization as it no longer has effect on the framework size. But it does have an effect on third party library. For example a simple project using `@ng-bootstrap/ng-bootstrap` goes from `444K` uncompressed with CLI `9.0.0-next.5` to `488K` with CLI `9.0.0-next.6` which introduced the removal.
diff --git a/packages/angular_devkit/build_angular/src/angular-cli-files/models/webpack-configs/common.ts b/packages/angular_devkit/build_angular/src/angular-cli-files/models/webpack-configs/common.ts
@@ -354,6 +354,7 @@ export function getCommonConfig(wco: WebpackConfigOptions): Configuration {
             }
           : {
               ecma: terserEcma,
+              pure_getters: buildOptions.buildOptimizer,
               // PURE comments work best with 3 passes.
               // See https://github.com/webpack/webpack/issues/2899#issuecomment-317425926.
               passes: buildOptions.buildOptimizer ? 3 : 1,

Original file line number	Diff line number	Diff line change
`@@ -354,6 +354,7 @@ export function getCommonConfig(wco: WebpackConfigOptions): Configuration {`
`354`	`354`	`}`
`355`	`355`	`: {`
`356`	`356`	`ecma: terserEcma,`
	`357`	`+ pure_getters: buildOptions.buildOptimizer,`
`357`	`358`	`// PURE comments work best with 3 passes.`
`358`	`359`	`// See https://github.com/webpack/webpack/issues/2899#issuecomment-317425926.`
`359`	`360`	`passes: buildOptions.buildOptimizer ? 3 : 1,`