Go 开发团队技术 leader Russ Cox 发文分享 Go 的版本控制历史

Russ Cox (rsc)发现每隔一段时间总会有人表示Go 的首次 commit 是在 1972 年 。rsc认为这种说法显然是非常愚蠢的，并分享了关于 Go 版本控制的更多有趣历史。例如： Go 真正首次 commit 是第 5 个 commit，此前的都是假 commit。

% git log --reverse --stat
commit 7d7c6a97f815e9279d08cfaea7d5efb5e90695a8
Author:     Brian Kernighan <bwk>
AuthorDate: Tue Jul 18 19:05:45 1972 -0500
Commit:     Brian Kernighan <bwk>
CommitDate: Tue Jul 18 19:05:45 1972 -0500

    hello, world

    R=ken
    DELTA=7  (7 added, 0 deleted, 0 changed)

 src/pkg/debug/macho/testdata/hello.b | 7 +++++++
 1 file changed, 7 insertions(+)

...

据rsc 所言，Go 使用过的版本控制系统共有 4 个：Subversion、Perforce、Mercurial 、Git。

commit 18c5b488a3b2e218c0e0cf2a7d4820d9da93a554
Author:     Robert Griesemer <[e-mail]>
AuthorDate: Sun Mar 2 20:47:34 2008 -0800
Commit:     Robert Griesemer <[e-mail]>
CommitDate: Sun Mar 2 20:47:34 2008 -0800

    Go spec starting point.

    SVN=111041

 doc/go_spec | 1197 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 1197 insertions(+)

Subversion

Go 开始使用 Subversion 是作为评估Subversion在Google内部推广使用的可行性实验，虽然最后没有选择 Subversion，但正是 Go 真正首次 commit提交到了 SVN 服务器。

Perforce

2008 年 7 月，Go 在 Subversion提交了最后一次 commit 。此后转向 Perforce，Go 开源前的大部分开发工作都是在 Perforce 上进行。

下面是 Go 迁移到 Perforce 的首次 commit：

commit 777ee7163bba96f2c9b3dfe135d8ad4ab837c062
Author:     Rob Pike <[e-mail]>
AuthorDate: Mon Jul 21 16:18:04 2008 -0700
Commit:     Rob Pike <[e-mail]>
CommitDate: Mon Jul 21 16:18:04 2008 -0700

    map delete

    SVN=128258

 doc/go_lang.txt | 6 ++++++
 1 file changed, 6 insertions(+)

commit 05caa7f82030327ccc9ae63a2b0121a029286501
Author:     Rob Pike <[e-mail]>
AuthorDate: Mon Jul 21 17:10:49 2008 -0700
Commit:     Rob Pike <[e-mail]>
CommitDate: Mon Jul 21 17:10:49 2008 -0700

    help management of empty pkg and lib directories in perforce

    R=gri
    DELTA=4  (4 added, 0 deleted, 0 changed)
    OCL=13328
    CL=13328

 lib/place-holder      | 2 ++
 pkg/place-holder      | 2 ++
 src/cmd/gc/mksys.bash | 0
 3 files changed, 4 insertions(+)

在转向到 Perforce 后，引入了DELTA=, OCL= 和 CL= 这些标签。并且许多其他变更具有相同的OCL=和CL=，因为它们是在单个Perforce命令中创建和提交的，没有经过审核。

commit c1f5eda7a2465dae196d1fa10baf6bfa9253808a
Author:     Rob Pike <[e-mail]>
AuthorDate: Mon Jul 21 18:06:39 2008 -0700
Commit:     Rob Pike <[e-mail]>
CommitDate: Mon Jul 21 18:06:39 2008 -0700

    change date

    OCL=13331
    CL=13331

 doc/go_lang.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Mercurial

2009 年 10 月，Go 的版本控制系统迁移到Mercurial，作为11月开源Go准备工作的一部分。

commit 942d6590d9005f89e971ed5af0374439a264a20e
Author:     Kai Backman <[e-mail]>
AuthorDate: Fri Oct 23 11:03:16 2009 -0700
Commit:     Kai Backman <[e-mail]>
CommitDate: Fri Oct 23 11:03:16 2009 -0700

    one more argsize fix. we were copying with the correct
    alignment but not enough (duh).

    R=rsc
    APPROVED=rsc
    DELTA=16  (13 added, 0 deleted, 3 changed)
    OCL=36020
    CL=36024

 src/cmd/5g/ggen.c |  2 +-
 test/arm-pass.txt | 17 +++++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

commit b74fd8ecb17c1959bbf2dbba6ccb8bae6bfabeb8
Author:     Kai Backman <[e-mail]>
AuthorDate: Fri Oct 23 12:43:01 2009 -0700
Commit:     Kai Backman <[e-mail]>
CommitDate: Fri Oct 23 12:43:01 2009 -0700

    fix build issue cause by transition to hg

    R=rsc
    http://go/go-review/1013012

 src/make-arm.bash | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Git

从 2009 年 11 月一直到 2014 年末，由于 Google Code Project Hosting 即将关闭，Go 不得已寻找新的代码托管方案。在研究了几个选项后，最终选择使用 Gerrit Code Review， rsc 认为这是 一个非常棒的选择。

commit 94151eb2799809ece7e44ce3212aa3cbb9520849
Author:     Russ Cox <[e-mail]>
AuthorDate: Fri Dec 5 21:33:07 2014 -0500
Commit:     Russ Cox <[e-mail]>
CommitDate: Fri Dec 5 21:33:07 2014 -0500

    encoding/xml: remove SyntaxError.Byte

    It is unused. It was introduced in the CL that added InputOffset.
    I suspect it was an editing mistake.

    LGTM=bradfitz
    R=bradfitz
    CC=golang-codereviews
    https://golang.org/cl/182580043

 src/encoding/xml/xml.go | 1 -
 1 file changed, 1 deletion(-)

commit 258f53dee33b9055ea168cb186f8c076edee5905
Author:     David Symonds <[e-mail]>
AuthorDate: Mon Dec 8 13:50:49 2014 +1100
Commit:     David Symonds <[e-mail]>
CommitDate: Mon Dec 8 13:50:49 2014 +1100

    remove .hgtags.

 .hgtags | 140 ----------------------------------------------------------------
 1 file changed, 140 deletions(-)

commit 369873c6e5d00314ae30276363f58e5af11b149c
Author:     David Symonds <[e-mail]>
AuthorDate: Mon Dec 8 13:50:49 2014 +1100
Commit:     David Symonds <[e-mail]>
CommitDate: Mon Dec 8 13:50:49 2014 +1100

    convert .hgignore to .gitignore.

 .hgignore => .gitignore | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

commit f33fc0eb95be84f0a688a62e25361a117e5b995b
Author:     David Symonds <[e-mail]>
AuthorDate: Mon Dec 8 13:53:11 2014 +1100
Commit:     David Symonds <[e-mail]>
CommitDate: Mon Dec 8 13:53:11 2014 +1100

    cmd/dist: convert dist from Hg to Git.

 src/cmd/dist/build.c | 100 ++++++++++++++++++++++++++++++---------------------
 1 file changed, 59 insertions(+), 41 deletions(-)

commit 26399948e3402d3512cb14fe5901afaef54482fa
Author:     David Symonds <[e-mail]>
AuthorDate: Mon Dec 8 11:39:11 2014 +1100
Commit:     David Symonds <[e-mail]>
CommitDate: Mon Dec 8 04:42:22 2014 +0000

    add bin/ to .gitignore.

    Change-Id: I5c788d324e56ca88366fb54b67240cebf5dced2c
    Reviewed-on: https://go-review.googlesource.com/1171
    Reviewed-by: Andrew Gerrand <[e-mail]>

 .gitignore | 1 +
 1 file changed, 1 insertion(+)

许多人认为 Go 托管在 GitHub 上，但 GitHub 只是问题跟踪器的主要来源：源代码的官方主要副本位于 go.googlesource.com。

至此，这就是Go转向第五个版本控制系统前的故事。

原文链接：https://research.swtch.com/govcs