From patchwork Thu Sep 10 07:32:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Denton Liu X-Patchwork-Id: 11766925 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D9CED618 for ; Thu, 10 Sep 2020 07:33:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B23D720795 for ; Thu, 10 Sep 2020 07:33:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="m4bDTg/j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729993AbgIJHc7 (ORCPT ); Thu, 10 Sep 2020 03:32:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726991AbgIJHcm (ORCPT ); Thu, 10 Sep 2020 03:32:42 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E4ACC061573 for ; Thu, 10 Sep 2020 00:32:42 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id f18so4121542pfa.10 for ; Thu, 10 Sep 2020 00:32:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=X07fjBNoq01iqUUTr4DhWgRcLn6b5141lFlA0uWwMWw=; b=m4bDTg/jgHaF2pVgCNtYYhBf/nv0XH9L/A7V4Coixq2XjzHiAoWLoEVFoPqtIVGHKw EsYrzGCwur5KuyfDZafEhTfgDeqkAkyi1zdHukLP2YUTbM0wFkMtuJFdJcg2jfVsnY42 wFz/CtbvkRe1wRT9knq950Va6xCsRl5fmC9M3yV5xJLF6rs6FXUywaQcsHvuz+8ccWjD ny3E079ddhS4CZTNRU/tjjEw41uyYV3N7gmJol1CNrryV0tg/FA6BzL1S5A4o6KVa+uV ZdJ4Ra8FghSF0AzkJtKxVAsqW9Hc2NMfA7+faH2pJhI7pUW90k0GISWNl6ZwYVfCplY4 uRJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=X07fjBNoq01iqUUTr4DhWgRcLn6b5141lFlA0uWwMWw=; b=kW6imEB1PTlo6lIRns5gwYSWliK4znE4mBOHqK6cyXwGsoaaaDQ9j3zfpSvwSnFeNN /R6aCJwMQ3Jrvd9iP7QVAIXSPMRVho5TPHjdYudo8Uiox98opFODy0ZOxhm3BRpyIiXd u7g+o/OfjaRyCLSgmilJZPCFfIMeA7gKJYkJVmLXq43kKiaGn0Xs3qi7axx0S1n/wovg htqZlnJv87d0QSKPg/edYzcfiyAsMDvTnKQs4SDBuiFDXd6GKhkemlILXaBYe3F1ctFC 4CgJaJ8Sofp2V7XCkO7AcpNXF83/m1tfzMMqjX52FgwikyNwwiSkFH4VlDSj62Yj57MD 7HlA== X-Gm-Message-State: AOAM530drCH7/81zKhUb75OOT5SfOpIskhm3fSiTX2xMrONhE8u3YSJ4 ij6FuZ7FTITZLbtpEp/7aZgHxVfGuLc= X-Google-Smtp-Source: ABdhPJxwTmpxDgUBIA2IgOe3j4NkxOe5xkr6Y9CvnZ8yuoIQWEzWQ7parr95BaD1vWgXqbnGk0iYpA== X-Received: by 2002:a62:878f:: with SMTP id i137mr3948185pfe.24.1599723161235; Thu, 10 Sep 2020 00:32:41 -0700 (PDT) Received: from archbookpro.hsd1.ca.comcast.net ([2601:647:5900:d670::1ab5]) by smtp.gmail.com with ESMTPSA id q127sm4990550pfb.61.2020.09.10.00.32.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Sep 2020 00:32:40 -0700 (PDT) From: Denton Liu To: Git Mailing List Cc: Junio C Hamano Subject: [PATCH v2 0/4] builtin/diff: learn --merge-base Date: Thu, 10 Sep 2020 00:32:16 -0700 Message-Id: X-Mailer: git-send-email 2.28.0.618.gf4bc123cb7 In-Reply-To: References: MIME-Version: 1.0 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org The range-notation in `git diff` has been cited as a mistake since diff compares two endpoints, not whole ranges.[0] In fact, the ranges seem to take on the opposite meanings when compared to range notation in `git log`. In an effort to reduce the use of range notation as much as possible, introduce the `--merge-base` flag, slightly modified from a suggestion by Jonathan Nieder.[1] This flag allows us to replace the first commit given on the command-line with its merge base between the first and second commits. This allows us to gently deprecate the `...` form entirely, although that is left as an exercise to the reader ;) One additional bonus is that this flag allows the "after" side to be not just constrained to a commit (like with `...` notation). It can now be the working tree or the index as well. The `--merge-base` name isn't very satisfying. If anyone has any better suggestions, please let me know. Changes since v1: * Implement Junio's documentation suggestions * Update git diff's usage to include this option [0]: https://lore.kernel.org/git/xmqqy2v26hu0.fsf@gitster-ct.c.googlers.com/ [1]: https://lore.kernel.org/git/20191223215928.GB38316@google.com/ Denton Liu (4): t4068: remove unnecessary >tmp git-diff.txt: backtick quote command text builtin/diff: parse --no-index using parse_options() builtin/diff: learn --merge-base Documentation/git-diff.txt | 40 +++++++++++----- builtin/diff.c | 94 +++++++++++++++++++++++++++++++++----- diff-no-index.c | 15 ++---- t/t4068-diff-symmetric.sh | 89 ++++++++++++++++++++++++++++++++++-- 4 files changed, 198 insertions(+), 40 deletions(-) Range-diff against v1: 1: 231ba3f661 ! 1: 4f219cf0d1 builtin/diff: learn --merge-base @@ Commit message Suggested-by: Jonathan Nieder + + ## Notes ## + The `--merge-base` name isn't very satisfying. If anyone has any + suggestions for alternative names, please let me know. + ## Documentation/git-diff.txt ## @@ Documentation/git-diff.txt: SYNOPSIS 'git diff' [] [] [--] [...] @@ Documentation/git-diff.txt: files on disk. +equivalent to `git diff $(git merge-base A B) B`. ++ +In the case where one commit is given, a diff is displayed between the -+merge base and the working tree or the index if `--cached` is given. -+`git diff --merge-base A` is equivalent to `git diff $(git merge-base A -+HEAD)`. ++merge base of the commit and the HEAD and the working tree or the index ++if `--cached` is given. `git diff --merge-base A` is equivalent to `git ++diff $(git merge-base A HEAD)`. ++ +In the case where no commits are given, this form behaves identically to +as if no `--merge-base` were supplied. @@ builtin/diff.c #define DIFF_NO_INDEX_EXPLICIT 1 #define DIFF_NO_INDEX_IMPLICIT 2 +@@ builtin/diff.c: static const char builtin_diff_usage[] = + "git diff [] [] [--] [...]\n" + " or: git diff [] --cached [] [--] [...]\n" + " or: git diff [] [...] [--] [...]\n" +-" or: git diff [] ...] [--] [...]\n" ++" or: git diff [] --merge-base [ []] [--] [...]\n" + " or: git diff [] ]\n" + " or: git diff [] --no-index [--] ]\n" + COMMON_DIFF_OPTIONS_HELP; @@ builtin/diff.c: int cmd_diff(int argc, const char **argv, const char *prefix) int blobs = 0, paths = 0; struct object_array_entry *blob[2]; @@ builtin/diff.c: int cmd_diff(int argc, const char **argv, const char *prefix) DIFF_NO_INDEX_EXPLICIT, PARSE_OPT_NONEG), + OPT_BOOL(0, "merge-base", &merge_base, -+ N_("use the merge base between the two commits as the diff base")), ++ N_("compare with the merge base between two commits")), OPT_END(), };