Extract the PHP version alias table into a shared script

README.md

@@ -53,7 +53,7 @@ This action is able to run certain test suites for Matomo or any Matomo plugin.
 
     Defines the PHP version to set up for testing. (Not needed for Client tests)
 
-    Use `matomo5_min_php`/`matomo5_max_php` (Matomo 5) or `matomo6_min_php`/`matomo6_max_php` (Matomo 6) to resolve to the centrally managed (defined in action.yml) minimum or maximum PHP versions supported by Matomo tests.
+    Use `matomo5_min_php`/`matomo5_max_php` (Matomo 5) or `matomo6_min_php`/`matomo6_max_php` (Matomo 6) to resolve to the centrally managed minimum or maximum PHP versions supported by Matomo tests. The alias table is `scripts/bash/resolve_php_version.sh`, so anything else needing these versions can resolve the same table instead of copying it.
 
     The action uses `shivammathur/setup-php` to set up PHP. You can find supported PHP versions here: https://github.com/shivammathur/setup-php#tada-php-support
 

action.yml

@@ -194,27 +194,13 @@ runs:
     - name: Resolve PHP version
       id: resolve-php
       shell: bash
+      # the alias table lives in scripts/bash/resolve_php_version.sh so anything else needing
+      # these versions resolves the same table instead of copying it. The input arrives through
+      # the environment rather than an expression, so a caller's value is never expanded as shell.
+      env:
+        PHP_VERSION_INPUT: ${{ inputs.php-version }}
       run: |
-        case "${{ inputs.php-version }}" in
-          matomo5_min_php)
-            RESOLVED_VERSION="7.2"
-            ;;
-          matomo5_max_php)
-            RESOLVED_VERSION="8.5"
-            ;;
-          matomo6_min_php)
-            RESOLVED_VERSION="8.1"
-            ;;
-          matomo6_max_php)
-            RESOLVED_VERSION="8.5"
-            ;;
-          '')
-            exit 0
-            ;;
-          *)
-            RESOLVED_VERSION="${{ inputs.php-version }}"
-            ;;
-        esac
+        RESOLVED_VERSION=$("${{ github.action_path }}/scripts/bash/resolve_php_version.sh" "$PHP_VERSION_INPUT")
 
         echo "version=$RESOLVED_VERSION" >> "$GITHUB_OUTPUT"
 

scripts/bash/resolve_php_version.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Resolves the centrally managed PHP version aliases to concrete versions, so that a caller can
+# track a Matomo major's floor or ceiling without repeating the number. Anything unrecognised is
+# echoed back unchanged, which is what lets callers pass a literal version such as 8.2. Empty
+# input echoes empty, which callers use to mean "do not set PHP up at all".
+#
+# Keeping the table in a script rather than inline in action.yml lets anything else that needs
+# these versions — including workflows in other repositories, which can check this repository
+# out — resolve the same table instead of copying it. A copy drifts exactly when a floor moves,
+# which is the moment the value matters.
+
+case "$1" in
+  matomo5_min_php)
+    RESOLVED_VERSION="7.2"
+    ;;
+  matomo5_max_php)
+    RESOLVED_VERSION="8.5"
+    ;;
+  matomo6_min_php)
+    RESOLVED_VERSION="8.1"
+    ;;
+  matomo6_max_php)
+    RESOLVED_VERSION="8.5"
+    ;;
+  *)
+    RESOLVED_VERSION="$1"
+    ;;
+esac
+
+printf '%s' "$RESOLVED_VERSION"