feat: importedModule helper to load modules in declarative way

Author: theKashey

README.md

@@ -174,6 +174,36 @@ What you could load using `useImported`? Everything - `imported` itself is using
 
 > 💡 did you know that there is another hook based solution to load _"something might might need"_? The [use-sidecar](https://github.com/theKashey/use-sidecar) pattern.
 
+🤔 Keep in mind - __everything here is using `useImported`__, and __you can build whatever you need__ using just it.
+
+### Module
+A slim helper to help handle `modules`, you might require using `useImported` in a component way
+```js
+import {importedModule, ImportedModule} from 'react-imported-component';
+
+const Moment = importedModule(() => import('moment'));
+
+<Moment fallback="long time ago">
+  {(momentjs /* default imports are auto-imported*/) => momentjs(date).fromNow()}
+</Moment>
+```
+> Yes, this example was taken from [loadable.lib](https://www.smooth-code.com/open-source/loadable-components/docs/library-splitting/)
+
+Can I also use a ref, populated when the library is loaded? No, you cant. Use `useImported` for any special case like this.
+
+Plus, there is a Component helper:
+```js
+<ImportedModule
+ // import is just a _trackable_ promise - do what ever you want
+ import={() => import('moment').then(({momentDefault})=> momentDefault(date).fromNow()} 
+ fallback="long time ago"
+>
+ {(fromNow) => fromNow()}
+</ImportedModule>
+``` 
+
+> ImportedModule will throw a promise to the nearest Suspense boundary if no `fallback` provided.
+
 ## Babel macro
 If you could not use babel plugin, but do have `babel-plugin-macro` (like CRA) - consider using macro API:
 ```js
@@ -224,6 +254,10 @@ If you have `imported` definition in one file, and use it from another - just `i
 - `loading` - is it loading right now?
 - `loadable` - the underlying `Loadable` object
 - `retry` - retry action (in case of error)
+
+Hints:
+- use `options.import=false` to perform conditional import - `importFunction` would not be used if this option set to `false.
+- use `options.track=true` to perform SSR only import - to usage would be tracked if this option set to `false.
 
 ##### Misc
 There is also API method, unique for imported-component, which could be useful on the client side

__tests__/module.spec.tsx

@@ -0,0 +1,48 @@
+import * as React from 'react';
+import {mount} from 'enzyme';
+import {act} from "react-dom/test-utils";
+
+import {importedModule, ImportedModule} from '../src/Module';
+import {done} from "../src/loadable";
+
+describe('Module Component', () => {
+
+  describe('hoc', () => {
+    it('should load component', async () => {
+      const Component = importedModule(() => Promise.resolve((x: number) => x + 42));
+
+      const wrapper = mount(<Component fallback={"loading"}>{(fn) => <span>{fn(42)}</span>}</Component>);
+
+      expect(wrapper.update().html()).toContain("loading");
+
+      await act(async () => {
+        await done();
+      });
+
+      expect(wrapper.update().html()).toContain("84");
+    });
+  });
+
+  describe('component', () => {
+    it('should load component', async () => {
+      const importer = () => Promise.resolve((x: number) => x + 42);
+
+      const wrapper = mount(
+        <ImportedModule
+          import={importer}
+          fallback={"loading"}
+        >
+          {(fn) => <span>{fn(42)}</span>}
+        </ImportedModule>
+      );
+
+      expect(wrapper.update().html()).toContain("loading");
+
+      await act(async () => {
+        await done();
+      });
+
+      expect(wrapper.update().html()).toContain("84");
+    });
+  })
+});

__tests__/useImported.spec.tsx

@@ -2,7 +2,7 @@ import * as React from 'react';
 import {mount} from 'enzyme';
 import {act} from "react-dom/test-utils";
 import {useLoadable, useImported} from '../src/useImported';
-import {toLoadable, getLoadable} from "../src/loadable";
+import {toLoadable, getLoadable, done} from "../src/loadable";
 import {drainHydrateMarks} from "../src";
 
 
@@ -15,8 +15,6 @@ describe('useLoadable', () => {
     const Component = () => {
       const used = useLoadable(loadable);
     }
-
-
   });
 });
 
@@ -91,4 +89,39 @@ describe('useImported', () => {
     expect(wrapper.html()).toContain("error");
     expect(drainHydrateMarks()).toEqual([]);
   });
+
+  it('conditional import', async () => {
+    const importer = () => importedWrapper('imported_mark1_component', Promise.resolve(() => <span>loaded!</span>));
+
+    const Comp = ({loadit}) => {
+      const {loading, imported: Component,} = useImported(importer, undefined, {import: loadit});
+
+      if (Component) {
+        return <Component/>
+      }
+
+      if (loading) {
+        return <span>loading</span>;
+      }
+      return <span>nothing</span>;
+    };
+
+    const wrapper = mount(<Comp loadit={false}/>);
+    expect(wrapper.html()).toContain("nothing");
+
+    await act(async () => {
+      await Promise.resolve();
+    });
+
+    expect(wrapper.update().html()).toContain("nothing");
+    wrapper.setProps({loadit: true});
+    expect(wrapper.update().html()).toContain("nothing");
+
+    await act(async () => {
+      await done();
+    });
+
+    expect(wrapper.update().html()).toContain("loaded!");
+    expect(drainHydrateMarks()).toEqual(["mark1"]);
+  })
 });

examples/CRA/package.json

@@ -15,7 +15,7 @@
     "typescript": "3.3.3"
   },
   "scripts": {
-    "start": "react-scripts start",
+    "start": "imported-components src async-imports.js && react-scripts start",
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom",
     "eject": "react-scripts eject"

package.json

@@ -63,7 +63,6 @@
     "crc-32": "^1.2.0",
     "detect-node": "^2.0.4",
     "prop-types": "^15.6.2",
-    "react-uid": "^2.2.0",
     "scan-directory": "^1.0.0",
     "tslib": "^1.10.0"
   },

src/Component.tsx

@@ -1,6 +1,5 @@
 import * as React from 'react';
 import {ReactElement} from "react";
-import {uid} from "react-uid";
 
 import {settings} from './config';
 import {ComponentOptions} from "./types";
@@ -20,7 +19,7 @@ function ImportedComponent<P, K>(props: ComponentOptions<P, K>): ReactElement |
 
   if (Component) {
     // importedUUID for cache busting
-    return <Component {...props.forwardProps} ref={props.forwardRef} importedUUID={uid(Component)}/>
+    return <Component {...props.forwardProps} ref={props.forwardRef} />
   }
 
   if (loading) {

src/HOC.tsx

@@ -1,9 +1,10 @@
 import * as React from 'react';
+import {useMemo} from "react";
+
 import {ImportedComponent} from './Component';
 import {getLoadable} from './loadable';
 import {ComponentOptions, DefaultComponentImport, HOCOptions, HOCType, LazyImport} from "./types";
 import {useLoadable} from "./useImported";
-import {useMemo} from "react";
 import {asDefault} from "./utils";
 import {isBackend} from "./detectBackend";
 

src/Module.tsx

@@ -0,0 +1,48 @@
+import * as React from "react";
+import {
+  DefaultImport,
+  FullImportModuleProps,
+  HOCModuleType,
+  ImportModuleProps,
+
+} from "./types";
+import {useImported} from "./useImported";
+import {getLoadable} from "./loadable";
+
+
+export function ImportedModule<T>(props: FullImportModuleProps<T>) {
+  const {error, loadable, imported: module} = useImported(props.import);
+  if (error) {
+    throw error;
+  }
+  if (module) {
+    return props.children(module);
+  }
+  if (!props.fallback){
+    throw loadable.resolution;
+  }
+  return props.fallback as any;
+}
+
+export function importedModule<T>(
+  loaderFunction: DefaultImport<T>
+): HOCModuleType<T> {
+  const loadable = getLoadable(loaderFunction);
+
+  const Module = ((props: ImportModuleProps<T>) => (
+    <ImportedModule
+      {...props}
+      import={loadable}
+      fallback={props.fallback}
+    />
+  )) as HOCModuleType<T>;
+
+  Module.preload = () => {
+    loadable.load().catch(() => ({}));
+
+    return loadable.resolution;
+  };
+  Module.done = loadable.resolution;
+
+  return Module;
+}

src/babel.ts

@@ -30,7 +30,7 @@ const templateOptions = {
   placeholderPattern: /^([A-Z0-9]+)([A-Z0-9_]+)$/,
 };
 
-export const createTransformer = ({types: t, template}: any) => {
+export const createTransformer = ({types: t, template}: any, excludeMacro = false) => {
   const headerTemplate = template(`var importedWrapper = function(marker, realImport) { 
       if (typeof __deoptimization_sideEffect__ !== 'undefined') {
         __deoptimization_sideEffect__(marker, realImport);
@@ -50,6 +50,10 @@ export const createTransformer = ({types: t, template}: any) => {
     traverse(programPath: any, fileName: string) {
       programPath.traverse({
         ImportDeclaration(path: any) {
+          if(excludeMacro){
+            return;
+          }
+
           const source = path.node.source.value;
           if (source === 'react-imported-component/macro') {
             const {specifiers} = path.node;

src/config.ts

@@ -6,7 +6,8 @@ export const settings = {
   hot: (!!module as any).hot,
   SSR: isBackend,
   rethrowErrors: process.env.NODE_ENV !== 'production',
-  fileFilter: rejectNetwork
+  fileFilter: rejectNetwork,
+  updateOnReload: false,
 };
 
 export const setConfiguration = (config: Partial<typeof settings>) => {