fix: update method for extracting major version (#1007)

Author: baseballyama

.changeset/two-students-pump.md

@@ -0,0 +1,5 @@
+---
+'eslint-plugin-svelte': patch
+---
+
+fix: update method for extracting major version

packages/eslint-plugin-svelte/src/utils/svelte-context.ts

@@ -145,7 +145,7 @@ function getSvelteVersion(filePath: string): SvelteContext['svelteVersion'] {
 			if (typeof version !== 'string') {
 				continue;
 			}
-			const major = version.split('.')[0];
+			const major = extractMajorVersion(version, false);
 			if (major === '3' || major === '4') {
 				return '3/4';
 			}
@@ -185,7 +185,8 @@ function getSvelteKitVersion(filePath: string): SvelteContext['svelteKitVersion'
 			if (typeof version !== 'string') {
 				return null;
 			}
-			return version.split('.')[0] as SvelteContext['svelteKitVersion'];
+
+			return extractMajorVersion(version, true) as SvelteContext['svelteKitVersion'];
 		}
 	} catch {
 		/** do nothing */
@@ -194,6 +195,21 @@ function getSvelteKitVersion(filePath: string): SvelteContext['svelteKitVersion'
 	return null;
 }
 
+function extractMajorVersion(version: string, recognizePrereleaseVersion: boolean): string | null {
+	if (recognizePrereleaseVersion) {
+		const match = /^(?:\^|~)?(\d+\.0\.0-next)/.exec(version);
+		if (match && match[1]) {
+			return match[1];
+		}
+	}
+
+	const match = /^(?:\^|~)?(\d+)\./.exec(version);
+	if (match && match[1]) {
+		return match[1];
+	}
+	return null;
+}
+
 /**
  * Gets a  project root folder path.
  * @param filePath A file path to lookup.