TypeScript @angular-compiler-src-output-js_emitter.JavaScriptEmitter类(方法)实例源码

export function emit() {
  var emitter = new JavaScriptEmitter(new SimpleJsImportGenerator());
  var emittedCode = emitter.emitStatements(
      assetUrl('compiler', 'output/output_emitter_codegen_untyped', 'test'), codegenStmts,
      codegenExportsVars);
  return emittedCode;
}

describe('JavaScriptEmitter', () => {
    let emitter: JavaScriptEmitter;
    let someVar: o.ReadVarExpr;

    beforeEach(() => { emitter = new JavaScriptEmitter(); });

    function emitSourceMap(stmt: o.Statement | o.Statement[], preamble?: string): SourceMap {
      const stmts = Array.isArray(stmt) ? stmt : [stmt];
      const source = emitter.emitStatements(someSourceFilePath, someGenFilePath, stmts, preamble);
      return extractSourceMap(source) !;
    }

    describe('source maps', () => {
      it('should emit an inline source map', () => {
        const source = new ParseSourceFile(';;;var', 'in.js');
        const startLocation = new ParseLocation(source, 0, 0, 3);
        const endLocation = new ParseLocation(source, 7, 0, 6);
        const sourceSpan = new ParseSourceSpan(startLocation, endLocation);
        const someVar = o.variable('someVar', null, sourceSpan);
        const sm = emitSourceMap(someVar.toStmt(), '/* MyPreamble \n */');

        expect(sm.sources).toEqual([someSourceFilePath, 'in.js']);
        expect(sm.sourcesContent).toEqual([' ', ';;;var']);
        expect(originalPositionFor(sm, {line: 3, column: 0}))
            .toEqual({line: 1, column: 3, source: 'in.js'});
      });
    });
  });

describe('JavaScriptEmitter', () => {
    let importResolver: ImportResolver;
    let emitter: JavaScriptEmitter;
    let someVar: o.ReadVarExpr;

    beforeEach(() => {
      importResolver = new SimpleJsImportGenerator();
      emitter = new JavaScriptEmitter(importResolver);
    });

    function emitSourceMap(
        stmt: o.Statement | o.Statement[], exportedVars: string[] = null): SourceMap {
      const stmts = Array.isArray(stmt) ? stmt : [stmt];
      const source = emitter.emitStatements(someModuleUrl, stmts, exportedVars || []);
      return extractSourceMap(source);
    }

    describe('source maps', () => {
      it('should emit an inline source map', () => {
        const source = new ParseSourceFile(';;;var', 'in.js');
        const startLocation = new ParseLocation(source, 0, 0, 3);
        const endLocation = new ParseLocation(source, 7, 0, 6);
        const sourceSpan = new ParseSourceSpan(startLocation, endLocation);
        const someVar = o.variable('someVar', null, sourceSpan);
        const sm = emitSourceMap(someVar.toStmt());

        expect(sm.sources).toEqual(['in.js']);
        expect(sm.sourcesContent).toEqual([';;;var']);
        expect(originalPositionFor(sm, {line: 1, column: 0}))
            .toEqual({line: 1, column: 3, source: 'in.js'});
      });
    });
  });

describe('JavaScriptEmitter', () => {
    let emitter: JavaScriptEmitter;
    let someVar: o.ReadVarExpr;

    beforeEach(() => {
      emitter = new JavaScriptEmitter(new SimpleJsImportGenerator());
      someVar = o.variable('someVar');
    });

    function emitStmt(stmt: o.Statement, exportedVars: string[] = null): string {
      if (!exportedVars) {
        exportedVars = [];
      }
      return emitter.emitStatements(someModuleUrl, [stmt], exportedVars);
    }

    it('should declare variables', () => {
      expect(emitStmt(someVar.set(o.literal(1)).toDeclStmt())).toEqual(`var someVar = 1;`);
      expect(emitStmt(someVar.set(o.literal(1)).toDeclStmt(), ['someVar'])).toEqual([
        'var someVar = 1;',
        `Object.defineProperty(exports, 'someVar', { get: function() { return someVar; }});`
      ].join('\n'));
    });

    it('should read and write variables', () => {
      expect(emitStmt(someVar.toStmt())).toEqual(`someVar;`);
      expect(emitStmt(someVar.set(o.literal(1)).toStmt())).toEqual(`someVar = 1;`);
      expect(emitStmt(someVar.set(o.variable('someOtherVar').set(o.literal(1))).toStmt()))
          .toEqual(`someVar = (someOtherVar = 1);`);
    });

    it('should read and write keys', () => {
      expect(emitStmt(o.variable('someMap').key(o.variable('someKey')).toStmt()))
          .toEqual(`someMap[someKey];`);
      expect(emitStmt(o.variable('someMap').key(o.variable('someKey')).set(o.literal(1)).toStmt()))
          .toEqual(`someMap[someKey] = 1;`);
    });

    it('should read and write properties', () => {
      expect(emitStmt(o.variable('someObj').prop('someProp').toStmt()))
          .toEqual(`someObj.someProp;`);
      expect(emitStmt(o.variable('someObj').prop('someProp').set(o.literal(1)).toStmt()))
          .toEqual(`someObj.someProp = 1;`);
    });

    it('should invoke functions and methods and constructors', () => {
      expect(emitStmt(o.variable('someFn').callFn([o.literal(1)]).toStmt())).toEqual('someFn(1);');
      expect(emitStmt(o.variable('someObj').callMethod('someMethod', [o.literal(1)]).toStmt()))
          .toEqual('someObj.someMethod(1);');
      expect(emitStmt(o.variable('SomeClass').instantiate([o.literal(1)]).toStmt()))
          .toEqual('new SomeClass(1);');
    });

    it('should support builtin methods', () => {
      expect(emitStmt(o.variable('arr1')
                          .callMethod(o.BuiltinMethod.ConcatArray, [o.variable('arr2')])
                          .toStmt()))
          .toEqual('arr1.concat(arr2);');

      expect(emitStmt(o.variable('observable')
                          .callMethod(o.BuiltinMethod.SubscribeObservable, [o.variable('listener')])
                          .toStmt()))
          .toEqual('observable.subscribe(listener);');

      expect(
          emitStmt(
              o.variable('fn').callMethod(o.BuiltinMethod.Bind, [o.variable('someObj')]).toStmt()))
          .toEqual('fn.bind(someObj);');
    });

    it('should support literals', () => {
      expect(emitStmt(o.literal(0).toStmt())).toEqual('0;');
      expect(emitStmt(o.literal(true).toStmt())).toEqual('true;');
      expect(emitStmt(o.literal('someStr').toStmt())).toEqual(`'someStr';`);
      expect(emitStmt(o.literalArr([o.literal(1)]).toStmt())).toEqual(`[1];`);
      expect(emitStmt(o.literalMap([['someKey', o.literal(1)]]).toStmt())).toEqual(`{someKey: 1};`);
    });

    it('should support blank literals', () => {
      expect(emitStmt(o.literal(null).toStmt())).toEqual('null;');
      expect(emitStmt(o.literal(undefined).toStmt())).toEqual('undefined;');
    });

    it('should support external identifiers', () => {
      expect(emitStmt(o.importExpr(sameModuleIdentifier).toStmt())).toEqual('someLocalId;');
      expect(emitStmt(o.importExpr(externalModuleIdentifier).toStmt())).toEqual([
        `var import0 = re` +
            `quire('somePackage/someOtherPath');`,
        `import0.someExternalId;`
      ].join('\n'));
    });

    it('should support operators', () => {
      const lhs = o.variable('lhs');
      const rhs = o.variable('rhs');
      expect(emitStmt(o.not(someVar).toStmt())).toEqual('!someVar;');
      expect(
          emitStmt(someVar.conditional(o.variable('trueCase'), o.variable('falseCase')).toStmt()))
          .toEqual('(someVar? trueCase: falseCase);');

//.........这里部分代码省略.........

function emitSourceMap(
     stmt: o.Statement | o.Statement[], exportedVars: string[] = null,
     preamble?: string): SourceMap {
   const stmts = Array.isArray(stmt) ? stmt : [stmt];
   const source = emitter.emitStatements(
       someSourceFilePath, someGenFilePath, stmts, exportedVars || [], preamble);
   return extractSourceMap(source);
 }

function emitStmt(stmt: o.Statement, exportedVars: string[] = null): string {
   if (!exportedVars) {
     exportedVars = [];
   }
   return emitter.emitStatements(someModuleUrl, [stmt], exportedVars);
 }

function emitStmt(stmt: o.Statement, exportedVars: string[] = null): string {
   const source = emitter.emitStatements(someModuleUrl, [stmt], exportedVars || []);
   return stripSourceMapAndNewLine(source);
 }

function emitStmt(stmt: o.Statement, preamble?: string): string {
   const source = emitter.emitStatements(someGenFilePath, [stmt], preamble);
   return stripSourceMapAndNewLine(source);
 }

function emitSourceMap(
     stmt: o.Statement | o.Statement[], exportedVars: string[] = null): SourceMap {
   const stmts = Array.isArray(stmt) ? stmt : [stmt];
   const source = emitter.emitStatements(someModuleUrl, stmts, exportedVars || []);
   return extractSourceMap(source);
 }

function emitSourceMap(stmt: o.Statement | o.Statement[], preamble?: string): SourceMap {
   const stmts = Array.isArray(stmt) ? stmt : [stmt];
   const source = emitter.emitStatements(someGenFilePath, stmts, preamble);
   return extractSourceMap(source) !;
 }