fix: throw descriptive errors

src/base.ts

@@ -1,3 +1,5 @@
+import { MissingRequiredKeyError } from "./error"
+
 export class CaseCopyMap extends Map<string, string> {
 	set(key: string, value: string): this {
 		super.set(`case_copying${key.toLowerCase()}`, key)
@@ -24,12 +26,26 @@ export class APTBase {
 	 */
 	protected raw: CaseCopyMap
 
+
+	/**
+	 * Raw-accessible list of the required APT keys
+	 */
+	protected required: string[]
+
 	/**
 	 * Base constructor.
 	 * This should never be used.
 	 */
-	constructor() {
+	constructor(required: string[]) {
 		this.raw = new CaseCopyMap()
+		this.required = required
+
+		for (const key of this.required) {
+			if (!this.raw.has(key)) {
+				throw new MissingRequiredKeyError(key)
+			}
+		}
+
 	}
 
 	/**

src/control.ts

@@ -234,35 +234,41 @@ export interface IBinaryControl {
  */
 export class BinaryControl extends APTBase implements IBinaryControl {
 	// Begin Raw Implementation
-		package: string
-		source?: string | undefined
-		version: string
-		section?: string | undefined
-		priority?: PriorityLevel | undefined
-		architecture: string
-		essential?: boolean | undefined
-		depends?: string[] | undefined
-		preDepends?: string[] | undefined
-		recommends?: string[] | undefined
-		suggests?: string[] | undefined
-		replaces?: string[] | undefined
-		enhances?: string[] | undefined
-		breaks?: string[] | undefined
-		conflicts?: string[] | undefined
-		installedSize?: number | undefined
-		maintainer: string
-		description: string
-		homepage?: string | undefined
-		builtUsing?: string | undefined
-		packageType?: PackageType | undefined
+	package: string
+	source?: string | undefined
+	version: string
+	section?: string | undefined
+	priority?: PriorityLevel | undefined
+	architecture: string
+	essential?: boolean | undefined
+	depends?: string[] | undefined
+	preDepends?: string[] | undefined
+	recommends?: string[] | undefined
+	suggests?: string[] | undefined
+	replaces?: string[] | undefined
+	enhances?: string[] | undefined
+	breaks?: string[] | undefined
+	conflicts?: string[] | undefined
+	installedSize?: number | undefined
+	maintainer: string
+	description: string
+	homepage?: string | undefined
+	builtUsing?: string | undefined
+	packageType?: PackageType | undefined
 	// End Raw Implementation
 
 	/**
 	 * Create a type-safe Control object and populate its keys
 	 * @param {string} rawData Contents of a control file from a debian binary
 	 */
-	 constructor(rawData: string) {
-		super()
+	constructor(rawData: string) {
+		super([
+			'Package',
+			'Version',
+			'Architecture',
+			'Maintainer',
+			'Description'
+		])
 
 		const map = parseKV(rawData)
 		this.raw = map

src/error.ts

@@ -0,0 +1,8 @@
+export class MissingRequiredKeyError extends Error {
+	constructor(key: string) {
+		super()
+
+		this.name = 'MissingRequiredKeyError'
+		this.message = `Missing Required APT Key: ${key}`
+	}
+}

src/packages.ts

@@ -99,6 +99,10 @@ export class Package extends BinaryControl implements IPackage {
 	 */
 	constructor(rawData: string) {
 		super(rawData)
+		super.required = [
+			'Filename',
+			'Size'
+		]
 
 		this.filename = this.raw.get('Filename')!.trim()
 		this.size = parseFloat(this.raw.get('Size')!.trim())

src/release.ts

@@ -259,7 +259,10 @@ export class Release extends APTBase implements IRelease {
 	 * @param {string} rawData Contents of a Release file from an APT repository
 	 */
 	constructor(rawData: string) {
-		super()
+		super([
+			'Architectures',
+			'Components'
+		])
 
 		const map = parseKV(rawData)
 		this.raw = map