Add optionality for parameters

This commit allows for parameters that does not require any arguments to
be provided in function calls. It changes collection syntax where
parameters are list of objects instead of primitive strings. A
parameter has now 'name' and 'optional' properties. 'name' is required
and used in same way as older strings as parameter definitions.
'Optional' property is optional, 'false' is the default behavior if
undefined. It also adds additional validation to restrict parameter
names to alphanumeric strings to have a clear syntax in expressions.

tests/unit/application/Parser/Script/Compiler/FunctionCall/FunctionCall.spec.ts

@@ -0,0 +1,51 @@
+import 'mocha';
+import { expect } from 'chai';
+import { FunctionCall } from '@/application/Parser/Script/Compiler/FunctionCall/FunctionCall';
+import { IReadOnlyFunctionCallArgumentCollection } from '@/application/Parser/Script/Compiler/FunctionCall/Argument/IFunctionCallArgumentCollection';
+import { FunctionCallArgumentCollectionStub } from '@tests/unit/stubs/FunctionCallArgumentCollectionStub';
+
+describe('FunctionCall', () => {
+    describe('ctor', () => {
+        it('throws when args is undefined', () => {
+            // arrange
+            const expectedError = 'undefined args';
+            const args = undefined;
+            // act
+            const act = () => new FunctionCallBuilder()
+                .withArgs(args)
+                .build();
+            // assert
+            expect(act).to.throw(expectedError);
+        });
+        it('throws when function name is undefined', () => {
+            // arrange
+            const expectedError = 'empty function name in function call';
+            const functionName = undefined;
+            // act
+            const act = () => new FunctionCallBuilder()
+                .withFunctionName(functionName)
+                .build();
+            // assert
+            expect(act).to.throw(expectedError);
+        });
+    });
+});
+
+class FunctionCallBuilder {
+    private functionName = 'functionName';
+    private args: IReadOnlyFunctionCallArgumentCollection = new FunctionCallArgumentCollectionStub();
+
+    public withFunctionName(functionName: string) {
+        this.functionName = functionName;
+        return this;
+    }
+
+    public withArgs(args: IReadOnlyFunctionCallArgumentCollection) {
+        this.args = args;
+        return this;
+    }
+
+    public build() {
+        return new FunctionCall(this.functionName, this.args);
+    }
+}