fix(isArrayLike): reject functions because functions have "length"

spec/observables/from-spec.ts

@@ -1,6 +1,7 @@
 import { expect } from 'chai';
 import { TestScheduler } from 'rxjs/testing';
-import { asyncScheduler, of, from, Observable, asapScheduler, Observer } from 'rxjs';
+import { asyncScheduler, of, from, Observable, asapScheduler, Observer, observable, Subject } from 'rxjs';
+import { first } from 'rxjs/operators';
 
 // tslint:disable:no-any
 declare const asDiagram: any;
@@ -118,5 +119,26 @@ describe('from', () => {
  );
  expect(nextInvoked).to.equal(false);
  });
+ it(`should accept a function`, (done) => {
+ const subject = new Subject();
+ const handler = (...args: any[]) => subject.next(...args);
+ handler[observable] = () => subject;
+ let nextInvoked = false;
+
+ from((handler as any)).pipe(first()).subscribe(
+ (x) => {
+ nextInvoked = true;
+ expect(x).to.equal('x');
+ },
+ (x) => {
+ done(new Error('should not be called'));
+ },
+ () => {
+ expect(nextInvoked).to.equal(true);
+ done();
+ }
+ );
+ handler('x');
+ });
  }
 });

src/internal/util/isArrayLike.ts

@@ -1 +1 @@
-export const isArrayLike = (<T>(x: any): x is ArrayLike<T> => x && typeof x.length === 'number');
+export const isArrayLike = (<T>(x: any): x is ArrayLike<T> => x && typeof x.length === 'number' && typeof x !== 'function');