From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FORGED_GMAIL_RCVD,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY shortcircuit=no autolearn=no autolearn_force=no version=3.4.2 Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by dcvr.yhbt.net (Postfix) with ESMTP id 8BF3E1F4B4 for ; Fri, 9 Oct 2020 14:19:59 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id A820A120906; Fri, 9 Oct 2020 23:19:09 +0900 (JST) Received: from o1678948x4.outbound-mail.sendgrid.net (o1678948x4.outbound-mail.sendgrid.net [167.89.48.4]) by neon.ruby-lang.org (Postfix) with ESMTPS id 63BBD1208D6 for ; Fri, 9 Oct 2020 23:19:06 +0900 (JST) Received: by filterdrecv-p3mdw1-6685f47d68-ckbbx with SMTP id filterdrecv-p3mdw1-6685f47d68-ckbbx-20-5F807143-5D 2020-10-09 14:18:43.848484736 +0000 UTC m=+142962.926912505 Received: from herokuapp.com (unknown) by ismtpd0049p1mdw1.sendgrid.net (SG) with ESMTP id QPYlGqKVQJGHvIma4UsbgQ for ; Fri, 09 Oct 2020 14:18:43.796 +0000 (UTC) Date: Fri, 09 Oct 2020 14:18:43 +0000 (UTC) From: universato@gmail.com Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 76214 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Bug X-Redmine-Issue-Id: 17257 X-Redmine-Issue-Author: universato X-Redmine-Sender: universato X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-SG-EID: =?us-ascii?Q?b0vA5U4nV4LCn7uQc1WDU+qE5iOqMsxSHQSZEBs9qDMXSPPfYyysHtfA1bBqYX?= =?us-ascii?Q?ePm=2Ffc9b4+KDyDuHJnQou5ni2h3=2FpxnAjpqtEXJ?= =?us-ascii?Q?oRg4RwmbFAynxXLIope6mVY=2Fbq0+4JT+6SZWRHJ?= =?us-ascii?Q?8qd+Cka24kmgD7IAMx9k5gs0T5boHDLt40ilAkb?= =?us-ascii?Q?Ltt9APaFYQAOz7C8QFI7y57qoaS5nI3S5xR6iT3?= =?us-ascii?Q?9ematRAVoXIR7aB7s=3D?= To: ruby-core@ruby-lang.org X-Entity-ID: b/2+PoftWZ6GuOu3b0IycA== X-ML-Name: ruby-core X-Mail-Count: 100348 Subject: [ruby-core:100348] [Ruby master Bug#17257] Integer#pow(0, 1) returns 1, which is incorrect X-BeenThere: ruby-core@ruby-lang.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: Ruby developers List-Id: Ruby developers List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #17257 has been reported by universato (Yoshimine Sato). ---------------------------------------- Bug #17257: Integer#pow(0, 1) returns 1, which is incorrect https://bugs.ruby-lang.org/issues/17257 * Author: universato (Yoshimine Sato) * Status: Open * Priority: Normal * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- Ruby 2.5.8, 2.6.6, 2.7.1 ```ruby p -1.pow(0, 1) #=> 1 p 0.pow(0, 1) #=> 1 p 1.pow(0, 1) #=> 1 p 1234567890.pow(0, 1) #=> 1 ``` These return value shoud be 0. Patch for test: Let's add some boundary value tests to `test_pow` of [test_numeric.rb](https://github.com/ruby/ruby/blob/e014e6bf6685f681998238ff005f6d161d43ce51/test/ruby/test_numeric.rb). ```ruby integers = [-2, -1, 0, 1, 2, 3, 6, 1234567890123456789] integers.each do |i| assert_equal(0, i.pow(0, 1), '[Bug #17257]') assert_equal(1, i.pow(0, 2)) assert_equal(1, i.pow(0, 3)) assert_equal(1, i.pow(0, 6)) assert_equal(1, i.pow(0, 1234567890123456789)) assert_equal(0, i.pow(0, -1)) assert_equal(-1, i.pow(0, -2)) assert_equal(-2, i.pow(0, -3)) assert_equal(-5, i.pow(0, -6)) assert_equal(-1234567890123456788, i.pow(0, -1234567890123456789)) end assert_equal(0, 0.pow(2, 1)) assert_equal(0, 0.pow(3, 1)) assert_equal(0, 2.pow(3, 1)) assert_equal(0, -2.pow(3, 1)) -- https://bugs.ruby-lang.org/