eapi7-ver.eclass: Initial implementation of ver_test().

This should strictly follow Algorithms 3.1 to 3.7 specified in PMS:
https://projects.gentoo.org/pms/6/pms.html#x1-310003.3

1 files changed, 123 insertions, 3 deletions

diff --git a/eclass/eapi7-ver.eclass b/eclass/eapi7-ver.eclass
index 6f8f0c0a1c37..1ad1cbe2edc2 100644
--- a/eclass/eapi7-ver.eclass
+++ b/eclass/eapi7-ver.eclass
@@ -16,8 +16,6 @@
 #
 # https://bugs.gentoo.org/482170
 #
-# Note: version comparison function is not included currently.
-#
 # @ROFF .SS
 # Version strings
 #
@@ -185,5 +183,127 @@ ver_rs() {
 # revision parts), and the comparison is performed according to
 # the algorithm specified in the PMS.
 ver_test() {
-	die "${FUNCNAME}: not implemented"
+	local v1 v2 op i tail result
+	local -a v1comp v2comp
+	local match=(
+		"+([0-9])*(.+([0-9]))"						# numeric components
+		"[a-z]"										# letter component
+		"*(@(_alpha|_beta|_pre|_rc|_p)*([0-9]))"	# suffixes
+		"-r+([0-9])"								# revision
+	)
+
+	local LC_ALL=C shopt_save=$(shopt -p extglob)
+	shopt -s extglob
+
+	if [[ $# -eq 2 ]]; then
+		v1=${PVR}
+	elif [[ $# -eq 3 ]]; then
+		v1=$1; shift
+	else
+		die "${FUNCNAME}: bad number of arguments"
+	fi
+	op=$1
+	v2=$2
+
+	case ${op} in
+		-eq|-ne|-lt|-le|-gt|-ge) ;;
+		*) die "${FUNCNAME}: invalid operator: ${op}" ;;
+	esac
+
+	# Test for both versions being valid, and split them into parts
+	for (( i=0; i<4; i++ )); do
+		tail=${v1##${match[i]}}
+		v1comp[i]=${v1%"${tail}"}
+		v1=${tail}
+		tail=${v2##${match[i]}}
+		v2comp[i]=${v2%"${tail}"}
+		v2=${tail}
+	done
+	# There must not be any remaining tail, and the numeric part
+	# must be non-empty.  All other parts are optional.
+	[[ -z ${v1} && -z ${v2} && -n ${v1comp[0]} && -n ${v2comp[0]} ]] \
+		|| die "${FUNCNAME}: invalid version"
+
+	# Compare numeric components (PMS algorithm 3.2)
+	_ver_cmp_num() {
+		local a=(${1//./ }) b=(${2//./ })
+		local an=${#a[@]} bn=${#b[@]}
+		local i
+		# First component
+		[[ 10#${a[0]} -gt 10#${b[0]} ]] && return 2
+		[[ 10#${a[0]} -lt 10#${b[0]} ]] && return 1
+		for (( i=1; i<an && i<bn; i++ )); do
+			# Other components (PMS algorithm 3.3)
+			if [[ ${a[i]} == 0* || ${b[i]} == 0* ]]; then
+				local ap=${a[i]%%*(0)} bp=${b[i]%%*(0)}
+				[[ ${ap} > ${bp} ]] && return 2
+				[[ ${ap} < ${bp} ]] && return 1
+			else
+				[[ ${a[i]} -gt ${b[i]} ]] && return 2
+				[[ ${a[i]} -lt ${b[i]} ]] && return 1
+			fi
+		done
+		[[ ${an} -gt ${bn} ]] && return 2
+		[[ ${an} -lt ${bn} ]] && return 1
+		return 0
+	}
+
+	# Compare letter components (PMS algorithm 3.4)
+	_ver_cmp_let() {
+		local a=$1 b=$2
+		[[ ${a} > ${b} ]] && return 2
+		[[ ${a} < ${b} ]] && return 1
+		return 0
+	}
+
+	# Compare suffixes (PMS algorithm 3.5)
+	_ver_cmp_suf() {
+		local a=(${1//_/ }) b=(${2//_/ })
+		local an=${#a[@]} bn=${#b[@]}
+		local i
+		for (( i=0; i<an && i<bn; i++ )); do
+			# Compare each suffix (PMS algorithm 3.6)
+			if [[ ${a[i]%%*([0-9])} == "${b[i]%%*([0-9])}" ]]; then
+				[[ 10#${a[i]##*([a-z])} -gt 10#${b[i]##*([a-z])} ]] && return 2
+				[[ 10#${a[i]##*([a-z])} -lt 10#${b[i]##*([a-z])} ]] && return 1
+			else
+				# Check for p first
+				[[ ${a[i]} == p*([0-9]) ]] && return 2
+				[[ ${b[i]} == p*([0-9]) ]] && return 1
+				# Hack: Use that alpha < beta < pre < rc alphabetically
+				[[ ${a[i]} > ${b[i]} ]] && return 2 || return 1
+			fi
+		done
+		if [[ ${an} -gt ${bn} ]]; then
+			[[ ${a[bn]} == p*([0-9]) ]] && return 2 || return 1
+		elif [[ ${an} -lt ${bn} ]]; then
+			[[ ${b[an]} == p*([0-9]) ]] && return 1 || return 2
+		fi
+		return 0
+	}
+
+	# Compare revision components (PMS algorithm 3.7)
+	_ver_cmp_rev() {
+		local a=${1#-r} b=${2#-r}
+		[[ 10#${a} -gt 10#${b} ]] && return 2
+		[[ 10#${a} -lt 10#${b} ]] && return 1
+		return 0
+	}
+
+	# Version comparison top-level logic (PMS algorithm 3.1)
+	_ver_cmp_num "${v1comp[0]}" "${v2comp[0]}" &&
+	_ver_cmp_let "${v1comp[1]}" "${v2comp[1]}" &&
+	_ver_cmp_suf "${v1comp[2]}" "${v2comp[2]}" &&
+	_ver_cmp_rev "${v1comp[3]}" "${v2comp[3]}"
+
+	case $? in
+		0) result=0  ;;			# a = b
+		1) result=-1 ;;			# a < b
+		2) result=1  ;;			# a > b
+		*) die "${FUNCNAME}: invalid return code: $?" ;;
+	esac
+
+	${shopt_save}
+
+	test "${result}" "${op}" 0
 }