Rename SUPPORT_PYTHON_ABIS to PYTHON_MULTIPLE_ABIS and RESTRICT_PYTHON_ABIS to PYTHON_RESTRICTED_ABIS in EAPI >=4.
(Patch by Arfrever. Backported from Progress Overlay.)
--- python.eclass
+++ python.eclass
@@ -91,14 +91,18 @@
 }
 
 _python_package_supporting_installation_for_multiple_python_abis() {
-	if has "${EAPI:-0}" 0 1 2 3 4; then
-		if [[ -n "${SUPPORT_PYTHON_ABIS}" ]]; then
+	if has "${EAPI:-0}" 0 1 2 3; then
+		if [[ -n "${PYTHON_MULTIPLE_ABIS}" || -n "${SUPPORT_PYTHON_ABIS}" ]]; then
 			return 0
 		else
 			return 1
 		fi
 	else
-		die "${FUNCNAME}(): Support for EAPI=\"${EAPI}\" not implemented"
+		if [[ -n "${PYTHON_MULTIPLE_ABIS}" ]]; then
+			return 0
+		else
+			return 1
+		fi
 	fi
 }
 
@@ -698,10 +702,25 @@
 # =========== FUNCTIONS FOR PACKAGES SUPPORTING INSTALLATION FOR MULTIPLE PYTHON ABIS ============
 # ================================================================================================
 
-# @ECLASS-VARIABLE: SUPPORT_PYTHON_ABIS
+if ! has "${EAPI:-0}" 0 1 2 3; then
+	if [[ -n "${SUPPORT_PYTHON_ABIS}" ]]; then
+		eerror "Use PYTHON_MULTIPLE_ABIS variable instead of SUPPORT_PYTHON_ABIS variable."
+		die "SUPPORT_PYTHON_ABIS variable is banned"
+	fi
+	if [[ -n "${RESTRICT_PYTHON_ABIS}" ]]; then
+		eerror "Use PYTHON_RESTRICTED_ABIS variable instead of RESTRICT_PYTHON_ABIS variable."
+		die "RESTRICT_PYTHON_ABIS variable is banned"
+	fi
+fi
+
+# @ECLASS-VARIABLE: PYTHON_MULTIPLE_ABIS
 # @DESCRIPTION:
-# Set this in EAPI <= 4 to indicate that current package supports installation for
-# multiple Python ABIs.
+# Set this to indicate that current package supports installation for multiple Python ABIs.
+
+# @ECLASS-VARIABLE: PYTHON_RESTRICTED_ABIS
+# @DESCRIPTION:
+# Space-separated list of Python ABI patterns. Support for Python ABIs matching any Python ABI
+# patterns specified in this list is disabled.
 
 # @ECLASS-VARIABLE: PYTHON_TESTS_RESTRICTED_ABIS
 # @DESCRIPTION:
@@ -788,6 +807,21 @@
 
 	_python_initial_sanity_checks
 
+	if has "${EAPI:-0}" 0 1 2 3; then
+		if [[ -z "${PYTHON_RESTRICTED_ABIS}" && -n "${RESTRICT_PYTHON_ABIS}" ]]; then
+			PYTHON_RESTRICTED_ABIS="${RESTRICT_PYTHON_ABIS}"
+		fi
+	else
+		if [[ -n "${SUPPORT_PYTHON_ABIS}" ]]; then
+			eerror "Use PYTHON_MULTIPLE_ABIS variable instead of SUPPORT_PYTHON_ABIS variable."
+			die "SUPPORT_PYTHON_ABIS variable is banned"
+		fi
+		if [[ -n "${RESTRICT_PYTHON_ABIS}" ]]; then
+			eerror "Use PYTHON_RESTRICTED_ABIS variable instead of RESTRICT_PYTHON_ABIS variable."
+			die "RESTRICT_PYTHON_ABIS variable is banned"
+		fi
+	fi
+
 	if [[ "$(declare -p PYTHON_ABIS 2> /dev/null)" != "declare -x PYTHON_ABIS="* ]] && has "${EAPI:-0}" 0 1 2 3 4; then
 		local PYTHON_ABI
 
@@ -807,7 +841,7 @@
 					cpython_enabled="1"
 				fi
 
-				if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${RESTRICT_PYTHON_ABIS}"; then
+				if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${PYTHON_RESTRICTED_ABIS}"; then
 					export PYTHON_ABIS+="${PYTHON_ABIS:+ }${PYTHON_ABI}"
 				fi
 			done
@@ -837,13 +871,13 @@
 
 				support_python_major_version="0"
 				for PYTHON_ABI in "${_CPYTHON2_GLOBALLY_SUPPORTED_ABIS[@]}"; do
-					if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${RESTRICT_PYTHON_ABIS}"; then
+					if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${PYTHON_RESTRICTED_ABIS}"; then
 						support_python_major_version="1"
 						break
 					fi
 				done
 				if [[ "${support_python_major_version}" == "1" ]]; then
-					if _python_check_python_abi_matching --patterns-list "${python2_version}" "${RESTRICT_PYTHON_ABIS}"; then
+					if _python_check_python_abi_matching --patterns-list "${python2_version}" "${PYTHON_RESTRICTED_ABIS}"; then
 						die "Active version of CPython 2 is not supported by ${CATEGORY}/${PF}"
 					fi
 				else
@@ -860,13 +894,13 @@
 
 				support_python_major_version="0"
 				for PYTHON_ABI in "${_CPYTHON3_GLOBALLY_SUPPORTED_ABIS[@]}"; do
-					if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${RESTRICT_PYTHON_ABIS}"; then
+					if ! _python_check_python_abi_matching --patterns-list "${PYTHON_ABI}" "${PYTHON_RESTRICTED_ABIS}"; then
 						support_python_major_version="1"
 						break
 					fi
 				done
 				if [[ "${support_python_major_version}" == "1" ]]; then
-					if _python_check_python_abi_matching --patterns-list "${python3_version}" "${RESTRICT_PYTHON_ABIS}"; then
+					if _python_check_python_abi_matching --patterns-list "${python3_version}" "${PYTHON_RESTRICTED_ABIS}"; then
 						die "Active version of CPython 3 is not supported by ${CATEGORY}/${PF}"
 					fi
 				else