Improve script/category name validation

- Use better error messages with more context.
- Unify their validation logic and share tests.
- Validate also type of the name.
- Refactor node (Script/Category) parser tests for easier future
  changes and cleaner test code (using `TestBuilder` to do dirty work in
  unified way).
- Add more tests. Custom `Error` properties are compared manually due to
  `chai` not supporting deep equality checks (chaijs/chai#1065,
  chaijs/chai#1405).

src/application/Parser/NodeValidation/NodeData.ts

@@ -0,0 +1,3 @@
+import type { ScriptData, CategoryData } from '@/application/collections/';
+
+export type NodeData = CategoryData | ScriptData;

src/application/Parser/NodeValidation/NodeDataError.ts

@@ -0,0 +1,35 @@
+import { NodeType } from './NodeType';
+import { NodeData } from './NodeData';
+
+export class NodeDataError extends Error {
+  constructor(message: string, public readonly context: INodeDataErrorContext) {
+    super(createMessage(message, context));
+    Object.setPrototypeOf(this, new.target.prototype); // https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-2.html#support-for-newtarget
+    this.name = new.target.name;
+  }
+}
+
+export interface INodeDataErrorContext {
+  readonly type?: NodeType;
+  readonly selfNode: NodeData;
+  readonly parentNode?: NodeData;
+}
+
+function createMessage(errorMessage: string, context: INodeDataErrorContext) {
+  let message = '';
+  if (context.type !== undefined) {
+    message += `${NodeType[context.type]}: `;
+  }
+  message += errorMessage;
+  message += `\n${dump(context)}`;
+  return message;
+}
+
+function dump(context: INodeDataErrorContext): string {
+  const printJson = (obj: unknown) => JSON.stringify(obj, undefined, 2);
+  let output = `Self: ${printJson(context.selfNode)}`;
+  if (context.parentNode) {
+    output += `\nParent: ${printJson(context.parentNode)}`;
+  }
+  return output;
+}

src/application/Parser/NodeValidation/NodeType.ts

@@ -0,0 +1,4 @@
+export enum NodeType {
+  Script,
+  Category,
+}

src/application/Parser/NodeValidation/NodeValidator.ts

@@ -0,0 +1,38 @@
+import { INodeDataErrorContext, NodeDataError } from './NodeDataError';
+import { NodeData } from './NodeData';
+
+export class NodeValidator {
+  constructor(private readonly context: INodeDataErrorContext) {
+
+  }
+
+  public assertValidName(nameValue: string) {
+    return this
+      .assert(
+        () => Boolean(nameValue),
+        'missing name',
+      )
+      .assert(
+        () => typeof nameValue === 'string',
+        `Name (${JSON.stringify(nameValue)}) is not a string but ${typeof nameValue}.`,
+      );
+  }
+
+  public assertDefined(node: NodeData) {
+    return this.assert(
+      () => node !== undefined && node !== null && Object.keys(node).length > 0,
+      'missing node data',
+    );
+  }
+
+  public assert(validationPredicate: () => boolean, errorMessage: string) {
+    if (!validationPredicate()) {
+      this.throw(errorMessage);
+    }
+    return this;
+  }
+
+  public throw(errorMessage: string) {
+    throw new NodeDataError(errorMessage, this.context);
+  }
+}