docs: create ripples api document (#8147)

* Generates a `material-ripple.html` API file in the material docs content. This can be used to show the ripple API information in material.angular.io.

Author: devversion

tools/dgeni/processors/component-grouper.ts

@@ -1,5 +1,5 @@
 import {CategorizedClassDoc} from './categorizer';
-import {DocCollection, Processor} from 'dgeni';
+import {DocCollection, Document, Processor} from 'dgeni';
 import * as path from 'path';
 
 /** Component group data structure. */
@@ -66,24 +66,13 @@ export class ComponentGrouper implements Processor {
     const groups = new Map<string, ComponentGroup>();
 
     docs.forEach(doc => {
-      // Full path to the file for this doc.
-      const basePath = doc.fileInfo.basePath;
-      const filePath = doc.fileInfo.filePath;
-
-      // All of the component documentation is under either `src/lib` or `src/cdk`.
-      // We group the docs up by the directory immediately under that root.
-      let packageName, packageDisplayName;
-      if (filePath.includes('cdk')) {
-        packageName = 'cdk';
-        packageDisplayName = 'CDK';
-      } else {
-        packageName = 'material';
-        packageDisplayName = 'Material';
-      }
+      const documentInfo = getDocumentPackageInfo(doc);
 
-      const displayName = path.relative(basePath, filePath).split(path.sep)[1];
-      const moduleImportPath = `@angular/${packageName}/${displayName}`;
-      const groupName = packageName + '-' + displayName;
+      const packageName = documentInfo.packageName;
+      const packageDisplayName = documentInfo.packageName === 'cdk' ? 'CDK' : 'Material';
+
+      const moduleImportPath = `@angular/${packageName}/${documentInfo.entryPointName}`;
+      const groupName = packageName + '-' + documentInfo.name;
 
       // Get the group for this doc, or, if one does not exist, create it.
       let group;
@@ -94,9 +83,8 @@ export class ComponentGrouper implements Processor {
         groups.set(groupName, group);
       }
 
-      group.displayName = displayName;
+      group.displayName = documentInfo.name;
       group.moduleImportPath = moduleImportPath;
-
       group.packageName = packageName;
       group.packageDisplayName = packageDisplayName;
 
@@ -115,3 +103,27 @@ export class ComponentGrouper implements Processor {
     return Array.from(groups.values());
   }
 }
+
+/** Resolves package information for the given Dgeni document. */
+function getDocumentPackageInfo(doc: Document) {
+  // Full path to the file for this doc.
+  const basePath = doc.fileInfo.basePath;
+  const filePath = doc.fileInfo.filePath;
+
+  // All of the component documentation is under either `src/lib` or `src/cdk`.
+  // We group the docs up by the directory immediately under that root.
+  const pathSegments = path.relative(basePath, filePath).split(path.sep);
+  let groupName = pathSegments[1];
+
+  // For the ripples there should be a component group in the docs. Even it's not a
+  // secondary-entry point it can be still documented with its own `material-ripple.html` file.
+  if (pathSegments[1] === 'core' && pathSegments[2] === 'ripple') {
+    groupName = 'ripple';
+  }
+
+  return {
+    name: groupName,
+    packageName: pathSegments[0] === 'lib' ? 'material' : pathSegments[0],
+    entryPointName: pathSegments[1],
+  };
+}