LU-15617 contrib: Add shellcheck to prepare-commit-msg

Add shellcheck verifiction to prepare-commit-msg.
SHELLCHECK_OPT export can be used to further add
option if the user wants. 'shellcheck' by deault
is set to 'yes' (SHELLCHECK_RUN="yes"). However,
it can be switched off by setting SHELLCHECK_RUN=
Tested on shellcheck version 0.8.0

Test-Parameters: trivial
Signed-off-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Change-Id: Id0603b26202b92f68d43b82a3b2d846dd634c20e
Reviewed-on: https://review.whamcloud.com/46705
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>

diff --git a/contrib/git-hooks/prepare-commit-msg b/contrib/git-hooks/prepare-commit-msg
index e4a94c9..2178e9e 100755 (executable)
--- a/contrib/git-hooks/prepare-commit-msg
+++ b/contrib/git-hooks/prepare-commit-msg
@@ -15,6 +15,9 @@
 
 CHECKPATCH=${CHECKPATCH:-contrib/scripts/checkpatch.pl}
 CHECKPATCH_OPTS=${CHECKPATCH_OPTS:-"--no-signoff --no-tree"}
+SHELLCHECK=${SHELLCHECK:-$(which shellcheck)}
+SHELLCHECK_OPTS=${SHELLCHECK_OPTS:-" -f gcc "}
+SHELLCHECK_RUN=${SHELLCHECK_RUN:-"yes"} # run everytime by default
 
 # If there are no comments in the commit, it is likely a rebase and
 # this shouldn't be adding new comments, or they appear in the commit.
@@ -37,6 +40,56 @@ if [ -x "$CHECKPATCH" ]; then
                sed -e 's/^/# /' >> "$1"
 fi
 
+# Add the shellcheck output as comments, but don't cause a commit error.
+if [[ -x "$SHELLCHECK" && "$SHELLCHECK_RUN" == "yes" ]]; then
+       # Add header
+       echo "#" >> "$1"
+       echo "# shellcheck output:" >> "$1"
+       echo "#" >> "$1"
+       # Get file that needs to be shellchecked. We only consider *.sh files
+       # Example Start --
+       #       modified:   lustre/tests/sanity.sh
+       #       modified:   contrib/git-hooks/prepare-commit-msg
+       #            new:   lustre/utils/liblustreapi_error.c
+       # Example End   --
+       mod_files=($(awk '/modified:.*\.sh|new:.*\.sh/ { print $3 }' $1))
+       for cur_file in ${mod_files[@]}; do
+               # Get start/end range of lines that needs to be reported
+               # range presently not used will come in handy when dealing with
+               # warnings reported by shellcheck
+               # Example 'git show' output Start --
+               #       @@ -29,6 +29,7 @@ DEF_STRIPE_COUNT=-1
+               # Example 'git show' output End   --
+               range=($(git show $cur_file | awk '/^@@/ { print $3 }' | \
+                       sed -e 's/+//' -e 's/,/ /'))
+               start_line=${range[0]}
+               end_line=$((start_line + ${range[1]}))
+
+               # 'shellcheck' reports errors/warnings/notes as below:
+               # Example start ---
+               #        sanity-lnet.sh:2319:13: error: Double quote array \
+               #        expansions to avoid re-splitting elements. [SC2068]
+               #
+               #        sanity-lnet.sh:2421:27: note: Double quote to prevent \
+               #        globbing and word splitting. [SC2086]
+               #
+               #        sanity-lnet.sh:2411:8: warning: Declare and assign \
+               #        separately to avoid masking return values. [SC2155]
+               # Example end   ---
+               $SHELLCHECK $SHELLCHECK_OPTS $cur_file |
+                       while IFS=": " read -r file line char mtype msg; do
+                       # Only filter out "errors" reported by shellcheck
+                       # We ignore "warnings" and "notes" for now.
+                       # TODO "Warnings" reported by shellcheck will come later
+                       [[ "$mtype" == "error" ]] || continue
+                       # Empty line we skip it.
+                       [[ -n "$line" ]] || continue
+                       echo "# $file:$line:$char $mtype: $msg" >> "$1"
+               done
+       done
+       echo "#" >> "$1"
+fi
+
 # Cause Vim to wrap text at 70 columns to match commit message style.
 # Adding a matching emacs modeline would be good, if I knew how to do that.
 echo "# vim:textwidth=70:" >> "$1"