WordPress Core versions check semver constraints

In repos we have a config file that determines the version of
WordPress Core that needs to be deployed to a live site.
This can be a full semver version (e.g. 1.2.3) or a "version"
that is actually a moveable tag related to a major release
(e.g. v6).

Previously, we did not check for this edge case, which means
that in some cases, we did not return a full semver version
and this caused a bug in updating language packs whereby
old language packs would be written into repos and lockfiles.

Now, we remove any leading 'v' characters and return a fully
qualified semver version (e.g. 1.2.3).

We make an assumption that the list of available core versions
(e.g. https://api.wordpress.org/translations/core/1.0/?version=6)
is ordered by most recent release first.

src/Dependencies/Updater.php

@@ -277,19 +277,6 @@ private function fetchDefault(string $src): \Result\Result
 		return $this->fetchRef($src, 'master');
 	}
 
-	/**
-	 * Version strings passed to WordPress APIs must not start with a v.
-	 *
-	 * So, v6.3.1 becomes 6.3.1.
-	 */
-	private function getCanonicalVersion($version)
-	{
-		if(str_starts_with($version, 'v')) {
-			return substr($version, 1);
-		}
-		return $version;
-	}
-
 	/**
 	 * Add a language pack to a lockfile, including translations for themes and plugins.
 	 *
@@ -301,7 +288,7 @@ private function getCanonicalVersion($version)
 	 */
 	private function addLanguageToLockfile(array $dep)
 	{
-		$wpCoreVersion = $this->getCanonicalVersion($this->get_wordpress_core_version());
+		$wpCoreVersion = $this->get_bare_version_number($this->get_wordpress_core_version());
 		$result = TranslationsApi::fetchLanguageSrcAndRevision(DependencyTypes::LANGUAGES, $dep['name'], $wpCoreVersion, null);
 		if ($result->isErr()) {
 			return $result;
@@ -317,7 +304,7 @@ private function addLanguageToLockfile(array $dep)
 				if(substr($version, 0, 18) === 'No tags for commit') {
 					continue;
 				} else {
-					$version = $this->getCanonicalVersion($version);
+					$version = $this->get_bare_version_number($version);
 				}
 				$result = TranslationsApi::fetchLanguageSrcAndRevision($type, $dep['name'], $version, $name);
 				if ($result->isErr()) {

src/Modules/Helpers/WhippetHelpers.php

@@ -72,14 +72,56 @@ public function load_application_config()
 		}
 	}
 
+	/**
+	 * Version strings passed to WordPress APIs must not start with a v.
+	 *
+	 * So, v6.3.1 becomes 6.3.1.
+	 */
+	public function get_bare_version_number($version)
+	{
+		if(substr($version, 0, 1) === 'v') {
+			return substr($version, 1);
+		}
+		return $version;
+	}
+
+	/** Given a version in config/application.json, return a valid WP Core version.
+	 *
+	 * Note that version numbers in repos can be of the following forms:
+	 *
+	 * v6
+	 * 6.3.2
+	 * 6.3
+	 * 6
+	 *
+	 * and should be translated into a full semver version, e.g. 6.3.2.
+	 */
 	public function get_wordpress_core_version()
 	{
 		$config_version = $this->application_config->wordpress->revision;
+		if (substr_count($config_version, '.') === 2) {
+			return $config_version;
+		}
 		if ($config_version == 'master') {
 			$latest_core_version = json_decode(file_get_contents('https://api.wordpress.org/core/version-check/1.7/'), JSON_OBJECT_AS_ARRAY);
 			return $latest_core_version['offers'][0]['version'];
 		}
-		return $config_version;
+		// Version does not include a patch version, so we need to find the
+		// fully qualified version humber from the JSON. We assume that the
+		// JSON data is ordered by most recent release first.
+		$latest_core_version = json_decode(file_get_contents('https://api.wordpress.org/core/version-check/1.7/'), JSON_OBJECT_AS_ARRAY);
+		$i = 0;
+		$canonical_version = $this->get_bare_version_number($config_version);
+		$ver_len = strlen($canonical_version);
+		while ($i < count($latest_core_version['offers'])) {
+			print_r("counter: {$i} canonical version: {$canonical_version}\n");
+			if (substr($latest_core_version['offers'][$i]['version'], 0, $ver_len) === $canonical_version) {
+				print_r("VERSION: {$latest_core_version['offers'][$i]['version']}\n");
+				return $latest_core_version['offers'][$i]['version'];
+			}
+			$i++;
+		}
+		throw new \Exception("WordPress core version not valid or no longer available: {$config_version}");
 	}
 
 	public function find_file($file, $include_dir = false)