fix(compiler): Collector collects enum values. (angular#9967)

Fixes: angular#9928

Author: chuckjaz

tools/@angular/tsc-wrapped/src/collector.ts

@@ -175,6 +175,46 @@ export class MetadataCollector {
           }
           // Otherwise don't record the function.
           break;
+        case ts.SyntaxKind.EnumDeclaration:
+          const enumDeclaration = <ts.EnumDeclaration>node;
+          let enumValueHolder: {[name: string]: MetadataValue} = {};
+          const enumName = enumDeclaration.name.text;
+          let nextDefaultValue: MetadataValue = 0;
+          let writtenMembers = 0;
+          for (const member of enumDeclaration.members) {
+            let enumValue: MetadataValue;
+            if (!member.initializer) {
+              enumValue = nextDefaultValue;
+            } else {
+              enumValue = evaluator.evaluateNode(member.initializer);
+            }
+            let name: string = undefined;
+            if (member.name.kind == ts.SyntaxKind.Identifier) {
+              const identifier = <ts.Identifier>member.name;
+              name = identifier.text;
+              enumValueHolder[name] = enumValue;
+              writtenMembers++;
+            }
+            if (typeof enumValue === 'number') {
+              nextDefaultValue = enumValue + 1;
+            } else if (name) {
+              nextDefaultValue = {
+                __symbolic: 'binary',
+                operator: '+',
+                left: {
+                  __symbolic: 'select',
+                  expression: {__symbolic: 'reference', name: enumName}, name
+                }
+              }
+            } else {
+              nextDefaultValue = errorSym('Unsuppported enum member name', member.name);
+            };
+          }
+          if (writtenMembers) {
+            if (!metadata) metadata = {};
+            metadata[enumName] = enumValueHolder;
+          }
+          break;
         case ts.SyntaxKind.VariableStatement:
           const variableStatement = <ts.VariableStatement>node;
           for (let variableDeclaration of variableStatement.declarationList.declarations) {

tools/@angular/tsc-wrapped/test/collector.spec.ts

@@ -15,7 +15,8 @@ describe('Collector', () => {
   beforeEach(() => {
     host = new Host(FILES, [
       '/app/app.component.ts', '/app/cases-data.ts', '/app/error-cases.ts', '/promise.ts',
-      '/unsupported-1.ts', '/unsupported-2.ts', 'import-star.ts', 'exported-functions.ts'
+      '/unsupported-1.ts', '/unsupported-2.ts', 'import-star.ts', 'exported-functions.ts',
+      'exported-enum.ts', 'exported-consts.ts'
     ]);
     service = ts.createLanguageService(host, documentRegistry);
     program = service.getProgram();
@@ -316,6 +317,26 @@ describe('Collector', () => {
       {__symbolic: 'reference', module: 'angular2/common', name: 'NgFor'}
     ]);
   });
+
+  it('should be able to collect the value of an enum', () => {
+    let enumSource = program.getSourceFile('/exported-enum.ts');
+    let metadata = collector.getMetadata(enumSource);
+    let someEnum: any = metadata.metadata['SomeEnum'];
+    expect(someEnum).toEqual({A: 0, B: 1, C: 100, D: 101});
+  });
+
+  it('should be able to collect enums initialized from consts', () => {
+    let enumSource = program.getSourceFile('/exported-enum.ts');
+    let metadata = collector.getMetadata(enumSource);
+    let complexEnum: any = metadata.metadata['ComplexEnum'];
+    expect(complexEnum).toEqual({
+      A: 0,
+      B: 1,
+      C: 30,
+      D: 40,
+      E: {__symbolic: 'reference', module: './exported-consts', name: 'constValue'}
+    });
+  });
 });
 
 // TODO: Do not use \` in a template literal as it confuses clang-format
@@ -548,6 +569,16 @@ const FILES: Directory = {
      return !!window.history.pushState;
     }
   `,
+  'exported-enum.ts': `
+    import {constValue} from './exported-consts';
+
+    export const someValue = 30;
+    export enum SomeEnum { A, B, C = 100, D };
+    export enum ComplexEnum { A, B, C = someValue, D = someValue + 10, E = constValue };
+  `,
+  'exported-consts.ts': `
+    export const constValue = 100;
+  `,
   'node_modules': {
     'angular2': {
       'core.d.ts': `

tools/tsc-watch/index.ts

@@ -89,8 +89,9 @@ if (platform == 'node') {
     start: 'File change detected. Starting incremental compilation...',
     error: 'error',
     complete: 'Compilation complete. Watching for file changes.',
-    onChangeCmds:
-        [['node', 'dist/tools/cjs-jasmine/index-tools', '--', 'tsc-wrapped/**/*{_,.}spec.js']]
+    onChangeCmds: [[
+      'node', 'dist/tools/cjs-jasmine/index-tools', '--', '@angular/tsc-wrapped/**/*{_,.}spec.js'
+    ]]
   });
 }