llvm-utils.eclass: Split out PATH prepending logic

Split the logic prepending PATH from pkg_setup() into a dedicated
llvm_prepend_path() function.

Signed-off-by: Michał Górny <mgorny@gentoo.org>

3 files changed, 61 insertions, 24 deletions

diff --git a/eclass/llvm-utils.eclass b/eclass/llvm-utils.eclass
index 43988f6f88c7..f308667e3dc2 100644
--- a/eclass/llvm-utils.eclass
+++ b/eclass/llvm-utils.eclass
@@ -112,4 +112,40 @@ llvm_fix_tool_path() {
 	${shopt_save}
 }
 
+# @FUNCTION: llvm_prepend_path
+# @USAGE: <slot>
+# @DESCRIPTION:
+# Prepend the path to the specified LLVM slot to PATH variable,
+# and reexport it.
+llvm_prepend_path() {
+	debug-print-function ${FUNCNAME} "${@}"
+
+	[[ ${#} -ne 1 ]] && die "Usage: ${FUNCNAME} <slot>"
+	local slot=${1}
+
+	local llvm_path=${ESYSROOT}/usr/lib/llvm/${slot}/bin
+	local IFS=:
+	local split_path=( ${PATH} )
+	local new_path=()
+	local x added=
+
+	# prepend new path in front of the first LLVM version found
+	for x in "${split_path[@]}"; do
+		if [[ ${x} == */usr/lib/llvm/*/bin ]]; then
+			if [[ ${x} != ${llvm_path} ]]; then
+				new_path+=( "${llvm_path}" )
+			elif [[ ${added} && ${x} == ${llvm_path} ]]; then
+				# deduplicate
+				continue
+			fi
+			added=1
+		fi
+		new_path+=( "${x}" )
+	done
+	# ...or to the end of PATH
+	[[ ${added} ]] || new_path+=( "${llvm_path}" )
+
+	export PATH=${new_path[*]}
+}
+
 fi
diff --git a/eclass/llvm.eclass b/eclass/llvm.eclass
index 05ffcfd7cc6d..e297fe992c9f 100644
--- a/eclass/llvm.eclass
+++ b/eclass/llvm.eclass
@@ -212,30 +212,7 @@ llvm_pkg_setup() {
 			llvm_fix_tool_path LLVM_CONFIG
 		fi
 
-		local prefix=${ESYSROOT}
-		local llvm_path=${prefix}/usr/lib/llvm/${LLVM_SLOT}/bin
-		local IFS=:
-		local split_path=( ${PATH} )
-		local new_path=()
-		local x added=
-
-		# prepend new path before first LLVM version found
-		for x in "${split_path[@]}"; do
-			if [[ ${x} == */usr/lib/llvm/*/bin ]]; then
-				if [[ ${x} != ${llvm_path} ]]; then
-					new_path+=( "${llvm_path}" )
-				elif [[ ${added} && ${x} == ${llvm_path} ]]; then
-					# deduplicate
-					continue
-				fi
-				added=1
-			fi
-			new_path+=( "${x}" )
-		done
-		# ...or to the end of PATH
-		[[ ${added} ]] || new_path+=( "${llvm_path}" )
-
-		export PATH=${new_path[*]}
+		llvm_prepend_path "${LLVM_SLOT}"
 	fi
 }
 
diff --git a/eclass/tests/llvm-utils.sh b/eclass/tests/llvm-utils.sh
index 44ad1b4adc84..5a46b25b7ad6 100755
--- a/eclass/tests/llvm-utils.sh
+++ b/eclass/tests/llvm-utils.sh
@@ -66,6 +66,21 @@ test_fix_tool_path() {
 	tend ${?}
 }
 
+test_prepend_path() {
+	local slot=${1}
+	local -x PATH=${2}
+	local expected=${3}
+
+	tbegin "llvm_prepend_path ${slot} to PATH=${PATH}"
+	llvm_prepend_path "${slot}"
+	if [[ ${PATH} != ${expected} ]]; then
+		eerror "llvm_prepend_path ${var}"
+		eerror "    gave: ${PATH}"
+		eerror "expected: ${expected}"
+	fi
+	tend ${?}
+}
+
 test_fix_clang_version CC clang 19.0.0git78b4e7c5 clang-19
 test_fix_clang_version CC clang 17.0.6 clang-17
 test_fix_clang_version CXX clang++ 17.0.6 clang++-17
@@ -79,4 +94,13 @@ test_fix_tool_path RANLIB llvm-ranlib 1
 test_fix_tool_path AR ar 1
 test_fix_tool_path AR ar 0
 
+ESYSROOT=
+test_prepend_path 17 /usr/bin /usr/bin:/usr/lib/llvm/17/bin
+test_prepend_path 17 /usr/lib/llvm/17/bin:/usr/bin /usr/lib/llvm/17/bin:/usr/bin
+test_prepend_path 17 /usr/bin:/usr/lib/llvm/17/bin /usr/bin:/usr/lib/llvm/17/bin
+test_prepend_path 18 /usr/lib/llvm/17/bin:/usr/bin \
+	/usr/lib/llvm/18/bin:/usr/lib/llvm/17/bin:/usr/bin
+test_prepend_path 18 /usr/bin:/usr/lib/llvm/17/bin \
+	/usr/bin:/usr/lib/llvm/18/bin:/usr/lib/llvm/17/bin
+
 texit