diffpkg: allow to choose between unified context and two columns

contrib/completion/zsh/_devtools.in

@@ -47,6 +47,8 @@ _diffpkg_args=(
 	'(-p --pkginfo)'{-p,--pkginfo}'[.PKGINFO diff mode]'
 	'(-b --buildinfo)'{-b,--buildinfo}'[.BUILDINFO diff mode]'
 	'(-m --makepkg-config)'{-m,--makepkg-config}'[Location of a makepkg config file]:makepkg_config:_files -g "*.conf(.)"'
+	'(-u -U --unified)'{-u,-U,--unified}'[Output 3 lines of unified context]'
+	'(-y --side-by-side)'{-y,--side-by-side}'[Output in two columns]'
 	'(-v --verbose)'{-v,--verbose}'[Provide more detailed/unfiltered output]'
 	'(-h --help)'{-h,--help}'[Display usage]'
 	'*:packages:_devtools_completions_all_packages'

doc/man/diffpkg.1.asciidoc

@@ -36,6 +36,15 @@ Options
 *-h, --help*::
 	Show a help text
 
+Output Options
+--------------
+
+*-u, -U, --unified*::
+	Output 3 lines of unified context
+
+*-y, --side-by-side*::
+	Output in two columns
+
 Modes
 -----
 

src/diffpkg.in

@@ -27,6 +27,10 @@ usage() {
 		    -v, --verbose        Provide more detailed/unfiltered output
 		    -h, --help           Show this help text
 
+		OUTPUT OPTIONS
+		    -u, -U, --unified    Output 3 lines of unified context
+		    -y, --side-by-side   Output in two columns
+
 		MODES
 		    -l, --list           Activate content list diff mode (default)
 		    -d, --diffoscope     Activate diffoscope diff mode
@@ -42,6 +46,9 @@ DIFFOSCOPE=0
 PKGINFO=0
 BUILDINFO=0
 
+DIFFMODE=--side-by-side
+DIFFOPTIONS=(--expand-tabs)
+
 # option checking
 while (( $# )); do
 	case $1 in
@@ -73,6 +80,14 @@ while (( $# )); do
 			VERBOSE=1
 			shift
 			;;
+		-u|-U|--unified)
+			DIFFMODE=--unified
+			shift
+			;;
+		-y|--side-by-side)
+			DIFFMODE=--side-by-side
+			shift
+			;;
 		--)
 			shift
 			break
@@ -86,6 +101,15 @@ while (( $# )); do
 	esac
 done
 
+if (( VERBOSE )); then
+	if [[ $DIFFMODE == --unified ]]; then
+		DIFFMODE="--unified=99999"
+	fi
+else
+	DIFFOPTIONS+=(--suppress-common-lines)
+fi
+DIFFOPTIONS+=("${DIFFMODE}")
+
 if ! (( DIFFOSCOPE || TARLIST || PKGINFO || BUILDINFO )); then
 	TARLIST=1
 fi
@@ -128,25 +152,27 @@ diff_pkgs() {
 	[[ -f $oldpkg ]] || die "No such file: %s" "${oldpkg}"
 	[[ -f $newpkg ]] || die "No such file: %s" "${newpkg}"
 
+	DIFFOPTIONS+=(--label "${oldpkg}" --label "${newpkg}")
+
 	if (( TARLIST )); then
 		tar_list "$oldpkg" > "$TMPDIR/filelist-old"
 		tar_list "$newpkg" > "$TMPDIR/filelist"
 
-		sdiff -s "$TMPDIR/filelist-old" "$TMPDIR/filelist"
+		diff "${DIFFOPTIONS[@]}" "$TMPDIR/filelist-old" "$TMPDIR/filelist"
 	fi
 
 	if (( PKGINFO )); then
 		bsdtar xOqf "$oldpkg" .PKGINFO > "$TMPDIR/pkginfo-old"
 		bsdtar xOqf "$newpkg" .PKGINFO > "$TMPDIR/pkginfo"
 
-		sdiff -s "$TMPDIR/pkginfo-old" "$TMPDIR/pkginfo"
+		diff "${DIFFOPTIONS[@]}" "$TMPDIR/pkginfo-old" "$TMPDIR/pkginfo"
 	fi
 
 	if (( BUILDINFO )); then
 		bsdtar xOqf "$oldpkg" .BUILDINFO > "$TMPDIR/buildinfo-old"
 		bsdtar xOqf "$newpkg" .BUILDINFO > "$TMPDIR/buildinfo"
 
-		sdiff -s "$TMPDIR/buildinfo-old" "$TMPDIR/buildinfo"
+		diff "${DIFFOPTIONS[@]}" "$TMPDIR/buildinfo-old" "$TMPDIR/buildinfo"
 	fi
 
 	if (( DIFFOSCOPE )); then