Add more and unify tests for absent object cases

- Unify test data for nonexistence of an object/string and collection.
- Introduce more test through adding missing test data to existing tests.
- Improve logic for checking absence of values to match tests.
- Add missing tests for absent value validation.
- Update documentation to include shared test functionality.

src/application/Parser/Script/Compiler/Function/SharedFunctionCollection.ts

@@ -5,7 +5,7 @@ export class SharedFunctionCollection implements ISharedFunctionCollection {
   private readonly functionsByName = new Map<string, ISharedFunction>();
 
   public addFunction(func: ISharedFunction): void {
-    if (!func) { throw new Error('undefined function'); }
+    if (!func) { throw new Error('missing function'); }
     if (this.has(func.name)) {
       throw new Error(`function with name ${func.name} already exists`);
     }
@@ -13,7 +13,7 @@ export class SharedFunctionCollection implements ISharedFunctionCollection {
   }
 
   public getFunctionByName(name: string): ISharedFunction {
-    if (!name) { throw Error('undefined function name'); }
+    if (!name) { throw Error('missing function name'); }
     const func = this.functionsByName.get(name);
     if (!func) {
       throw new Error(`called function is not defined "${name}"`);