[PATCH 9/9] remove #!interpreter line from shell libraries
From: Jonathan Nieder <hidden>
Date: 2016-06-15 22:59:19
Subsystem:
the rest · Maintainer:
Linus Torvalds
In a shell snippet meant to be sourced by other shell scripts, an
opening #! line does more harm than good.
The harm:
- When the shell library is sourced, the interpreter and options from
the #! line are not used. Specifying a particular shell can
confuse the reader into thinking it is safe for the shell library
to rely on idiosyncrasies of that shell.
- Using #! instead of a plain comment drops a helpful visual clue
that this is a shell library and not a self-contained script.
- Tools such as lintian can use a #! line to tell when an
installation script has failed by forgetting to set a script
executable. This check does not work if shell libraries also start
with a #! line.
The good:
- Text editors notice the #! line and use it for syntax highlighting
if you try to edit the installed scripts (without ".sh" suffix) in
place.
The use of the #! for file type detection is not needed because Git's
shell libraries are meant to be edited in source form (with ".sh"
suffix). Replace the opening #! lines with comments.
This involves tweaking the test harness's valgrind support to find
shell libraries by looking for "# " in the first line instead of "#!"
(see v1.7.6-rc3~7, 2011-06-17).
Suggested by Russ Allbery through lintian. Thanks to Jeff King and
Clemens Buchacher for further analysis.
Tested by searching for non-executable scripts with #! line:
find . -name .git -prune -o -type f -not -executable |
while read file
do
read line <"$file"
case $line in
'#!'*)
echo "$file"
;;
esac
done
The only remaining scripts found are templates for shell scripts
(unimplemented.sh, wrap-for-bin.sh) and sample input used in tests
(t/t4034/perl/{pre,post}).
Signed-off-by: Jonathan Nieder <redacted>
---
Thanks for reading.
contrib/completion/git-completion.bash | 2 --
contrib/completion/git-completion.tcsh | 2 --
git-mergetool--lib.sh | 3 +--
git-parse-remote.sh | 4 +++-
git-rebase--am.sh | 3 ++-
git-rebase--interactive.sh | 9 +++------
git-rebase--merge.sh | 4 +++-
git-sh-i18n.sh | 5 ++---
git-sh-setup.sh | 9 +++------
t/test-lib.sh | 6 ++----
10 files changed, 19 insertions(+), 28 deletions(-)
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index dba3c15..be61931 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash@@ -1,5 +1,3 @@ -#!bash -# # bash/zsh completion support for core Git. # # Copyright (C) 2006,2007 Shawn O. Pearce <spearce@spearce.org>
diff --git a/contrib/completion/git-completion.tcsh b/contrib/completion/git-completion.tcsh
index eaacaf0..6104a42 100644
--- a/contrib/completion/git-completion.tcsh
+++ b/contrib/completion/git-completion.tcsh@@ -1,5 +1,3 @@ -#!tcsh -# # tcsh completion support for core Git. # # Copyright (C) 2012 Marc Khouzam <marc.khouzam@gmail.com>
diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index a280f49..c45a020 100644
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh@@ -1,5 +1,4 @@ -#!/bin/sh -# git-mergetool--lib is a library for common merge tool functions +# git-mergetool--lib is a shell library for common merge tool functions : ${MERGE_TOOLS_DIR=$(git --exec-path)/mergetools}
diff --git a/git-parse-remote.sh b/git-parse-remote.sh
index 0e87e09..55fe8d5 100644
--- a/git-parse-remote.sh
+++ b/git-parse-remote.sh@@ -1,4 +1,6 @@ -#!/bin/sh +# This is a shell library to calculate the remote repository and +# upstream branch that should be pulled by "git pull" from the current +# branch. # git-ls-remote could be called from outside a git managed repository; # this would fail in that case and would issue an error message.
diff --git a/git-rebase--am.sh b/git-rebase--am.sh
index 34e3102..a4f683a 100644
--- a/git-rebase--am.sh
+++ b/git-rebase--am.sh@@ -1,4 +1,5 @@ -#!/bin/sh +# This shell script fragment is sourced by git-rebase to implement +# its default, fast, patch-based, non-interactive mode. # # Copyright (c) 2010 Junio C Hamano. #
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 3c6bed9..43c19e0 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh@@ -1,11 +1,8 @@ -#!/bin/sh +# This shell script fragment is sourced by git-rebase to implement +# its interactive mode. "git rebase --interactive" makes it easy +# to fix up commits in the middle of a series and rearrange commits. # # Copyright (c) 2006 Johannes E. Schindelin - -# SHORT DESCRIPTION -# -# This script makes it easy to fix up commits in the middle of a series, -# and rearrange commits. # # The original idea comes from Eric W. Biederman, in # http://article.gmane.org/gmane.comp.version-control.git/22407
diff --git a/git-rebase--merge.sh b/git-rebase--merge.sh
index 16d1817..e7d96de 100644
--- a/git-rebase--merge.sh
+++ b/git-rebase--merge.sh@@ -1,4 +1,6 @@ -#!/bin/sh +# This shell script fragment is sourced by git-rebase to implement +# its merge-based non-interactive mode that copes well with renamed +# files. # # Copyright (c) 2010 Junio C Hamano. #
diff --git a/git-sh-i18n.sh b/git-sh-i18n.sh
index 6a27f68..e6c3116 100644
--- a/git-sh-i18n.sh
+++ b/git-sh-i18n.sh@@ -1,9 +1,8 @@ -#!/bin/sh +# This shell library is Git's interface to gettext.sh. See po/README +# for usage instructions. # # Copyright (c) 2010 Ævar Arnfjörð Bjarmason # -# This is Git's interface to gettext.sh. See po/README for usage -# instructions. # Export the TEXTDOMAIN* data that we need for Git TEXTDOMAIN=git
diff --git a/git-sh-setup.sh b/git-sh-setup.sh
index ebfe8f7..190a539 100644
--- a/git-sh-setup.sh
+++ b/git-sh-setup.sh@@ -1,9 +1,6 @@ -#!/bin/sh -# -# This is included in commands that either have to be run from the toplevel -# of the repository, or with GIT_DIR environment variable properly. -# If the GIT_DIR does not look like the right correct git-repository, -# it dies. +# This shell scriplet is meant to be included by other shell scripts +# to set up some variables pointing at the normal git directories and +# a few helper shell functions. # Having this variable in your environment would break scripts because # you would cause "cd" to be taken to unexpected places. If you
diff --git a/t/test-lib.sh b/t/test-lib.sh
index c306bd0..c3e07b9 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh@@ -573,11 +573,9 @@ then make_valgrind_symlink () { # handle only executables, unless they are shell libraries that - # need to be in the exec-path. We will just use "#!" as a - # guess for a shell-script, since we have no idea what the user - # may have configured as the shell path. + # need to be in the exec-path. test -x "$1" || - test "#!" = "$(head -c 2 <"$1")" || + test "# " = "$(head -c 2 <"$1")" || return; base=$(basename "$1")
--
1.8.4.1