Adds pre support to versions

Changes migration to be from beta2

src/extension.ts

@@ -133,7 +133,7 @@ async function migrateSettings(context: ExtensionContext, previousVersion: strin
             }
         }
 
-        if (Versions.compare(previous, Versions.from(7, 3, 0)) !== 1) {
+        if (Versions.compare(previous, Versions.from(7, 3, 0, 'beta2')) !== 1) {
             const oldSection = 'advanced.maxQuickHistory';
             const inspection = configuration.inspect(oldSection);
             if (inspection !== undefined) {

src/system/version.ts

@@ -5,6 +5,7 @@ export namespace Versions {
         major: number;
         minor: number;
         patch: number;
+        pre?: string;
     }
 
     export function compare(v1: Version, v2: Version): number {
@@ -17,19 +18,26 @@ export namespace Versions {
         if (v1.patch > v2.patch) return 1;
         if (v1.patch < v2.patch) return -1;
 
+        if (v1.pre === undefined && v2.pre !== undefined) return 1;
+        if (v1.pre !== undefined && v2.pre === undefined) return -1;
+
+        if (v1.pre !== undefined && v2.pre !== undefined) return v1.pre.localeCompare(v2.pre);
+
         return 0;
     }
 
-    export function from(major: string | number, minor: string | number, patch: string | number): Version {
+    export function from(major: string | number, minor: string | number, patch: string | number, pre?: string): Version {
         return {
             major: typeof major === 'string' ? parseInt(major, 10) : major,
             minor: typeof minor === 'string' ? parseInt(minor, 10) : minor,
-            patch: typeof patch === 'string' ? parseInt(patch, 10) : patch
+            patch: typeof patch === 'string' ? parseInt(patch, 10) : patch,
+            pre: pre
         };
     }
 
     export function fromString(version: string): Version {
-        const [major, minor, patch] = version.split('.');
-        return from(major, minor, patch);
+        const [ver, pre] = version.split('-');
+        const [major, minor, patch] = ver.split('.');
+        return from(major, minor, patch, pre);
     }
 }