README.md

@@ -2,7 +2,7 @@
 
 This is a short introduction to the awesome Convertorizr hosted at https://conv.friedli.info/.
 
-Continuous integration is automated with Drone CI (![Build status of develop branch](https://ci.gittr.ch/api/badges/manuel/converter/status.svg?branch=develop)). Usage is self-explanatory. What else do you need to know?
+Continuous integration is automated with Drone CI ([![Build status of develop branch](https://ci.gittr.ch/api/badges/manuel/converter/status.svg?branch=develop)](https://ci.gittr.ch/manuel/converter)). Usage is self-explanatory. What else do you need to know?
 
 The source code is hosted at https://gittr.ch/manuel/converter.git.
 Contact the author at manuel-convertorizr|at|fritteli.ch.

package.json

@@ -24,8 +24,8 @@
     "start": "ng serve",
     "build": "ng build --delete-output-path",
     "build-prod": "ng build --prod --optimization --aot --delete-output-path --build-optimizer",
-    "test": "ng test",
-    "test:ci": "ng test --browsers ChromeHeadlessNoSandbox --watch=false",
+    "test": "ng test --code-coverage",
+    "test:ci": "ng test --browsers ChromeHeadlessNoSandbox --watch=false --code-coverage",
     "lint": "ng lint",
     "e2e": "ng e2e",
     "postinstall": "npm rebuild node-sass"

src/app/app.component.html

@@ -1,18 +1,7 @@
 <div *ngFor="let step of steps" class="inputwrapper">
-  <div class="textwrapper arrow_box">
-    <textarea class="textinput" (keyup)="update(step)" placeholder="Please enter your input ..."
-              [(ngModel)]="step.content">{{step.content}}</textarea>
-  </div>
-  <div [ngClass]="{selectwrapper: true, error: step.error}">
-    <div class="arrow_box">
-      <select class="select" (change)="convert(step, $event)">
-        <option id="undefined">Select conversion ...</option>
-        <option class="option" *ngFor="let c of converters" id="{{c.getId()}}">{{c.getDisplayname()}}
-        </option>
-      </select>
-    </div>
-  </div>
-  <div class="errormessage" *ngIf="step.error" [innerHTML]="step.message"></div>
+  <app-text-input-field [step]="step" #ti></app-text-input-field>
+  <app-converter-selector [step]="step" [textInput]="ti"></app-converter-selector>
+  <app-error-message [step]="step"></app-error-message>
 </div>
 <app-version></app-version>
 <!--<router-outlet></router-outlet>-->

src/app/app.component.scss

@@ -2,106 +2,3 @@
   font-family: "ABeeZee", sans-serif;
   margin: 0 1em 1em 1em;
 }
-
-.textwrapper {
-  margin: 0 0 1em 0;
-  padding: 0 1em 0 0;
-}
-
-.arrow_box {
-  position: relative;
-  background: #fff;
-  border: 1px solid #aaa;
-  &:focus {
-    border-color: #888;
-  }
-  &:hover {
-    border-color: #333;
-  }
-  &:after, &:before {
-    top: 100%;
-    left: 50%;
-    border: solid transparent;
-    content: " ";
-    height: 0;
-    width: 0;
-    position: absolute;
-    pointer-events: none;
-  }
-  &:after {
-    border-color: rgba(255, 255, 255, 0);
-    border-top-color: #fff;
-    border-width: 1em;
-    margin-left: -1em;
-  }
-  &:before {
-    border-color: rgba(170, 170, 170, 0);
-    border-top-color: #aaa;
-    border-width: calc(1em + 1px);
-    margin-left: calc(-1em - 1px);
-  }
-  &:focus:before {
-    border-color: rgba(136, 136, 136, 0);
-    border-top-color: #888;
-  }
-  &:hover:before {
-    border-color: rgba(51, 51, 51, 0);
-    border-top-color: #333;
-  }
-  .selectwrapper > & {
-    display: inline-block;
-  }
-}
-
-.textinput {
-  background-color: #fff;
-  border: none;
-  color: #000;
-  font-family: "Free Monospaced", monospace;
-  height: 10em;
-  margin: 0;
-  padding: 0.5em;
-  resize: vertical;
-  width: 100%;
-  &:focus {
-    border-color: #888;
-  }
-  &:hover {
-    border-color: #333;
-  }
-}
-
-.selectwrapper {
-  margin: 0 0 1em 0;
-  padding: 0;
-  text-align: center;
-  &.error {
-    > .arrow_box {
-      border-color: red;
-      &:before {
-        border-top-color: red;
-      }
-    }
-    select {
-      color: red;
-    }
-  }
-}
-
-.select {
-  background-color: #fff;
-  border: none;
-  color: #000;
-  font-family: "ABeeZee", sans-serif;
-  margin: 0;
-  padding: 0.5em;
-}
-
-.option {
-  /*    font-family: "ABeeZee", sans-serif;*/
-}
-
-.errormessage {
-  color: red;
-  text-align: center;
-}

src/app/app.component.spec.ts

@@ -1,32 +1,27 @@
 import {AppComponent} from './app.component';
 import {async, ComponentFixture, TestBed} from '@angular/core/testing';
 import {FormsModule} from '@angular/forms';
-import {InputComponentManagerService} from './input-component-manager.service';
 import {Step} from './step';
-import {ConverterRegistryService} from './converter-registry.service';
 import {VersionComponent} from './version/version.component';
-import createSpyObj = jasmine.createSpyObj;
+import {ConverterSelectorComponent} from './converter-selector/converter-selector.component';
+import {TextInputFieldComponent} from './text-input-field/text-input-field.component';
+import {ErrorMessageComponent} from './error-message/error-message.component';
 
 describe('AppComponent', () => {
   let sut: AppComponent;
   let fixture: ComponentFixture<AppComponent>;
   const firstStep: Step = new Step(0);
 
-  const inputComponentManagerServiceStub = createSpyObj(['getFirst']);
-  inputComponentManagerServiceStub.getFirst.and.returnValue(firstStep);
-
-  const converterRegistryServiceStub = createSpyObj(['getAllConverters', 'getConverter']);
-  converterRegistryServiceStub.getAllConverters.and.returnValue([]);
-  converterRegistryServiceStub.getConverter.and.returnValue(undefined);
-
   beforeEach(async(() => {
     TestBed.configureTestingModule({
-      declarations: [AppComponent, VersionComponent],
-      imports: [FormsModule],
-      providers: [
-        {provide: InputComponentManagerService, useValue: inputComponentManagerServiceStub},
-        {provide: ConverterRegistryService, useValue: converterRegistryServiceStub}
-      ]
+      declarations: [
+        AppComponent,
+        ConverterSelectorComponent,
+        ErrorMessageComponent,
+        TextInputFieldComponent,
+        VersionComponent
+      ],
+      imports: [FormsModule]
     })
       .compileComponents();
   }));

src/app/app.component.ts

@@ -1,8 +1,6 @@
 import {Component, OnInit} from '@angular/core';
-import {ConverterRegistryService} from './converter-registry.service';
 import {InputComponentManagerService} from './input-component-manager.service';
 import {Step} from './step';
-import {Converter} from './converter/converter';
 
 @Component({
   selector: 'app-root',
@@ -11,47 +9,11 @@ import {Converter} from './converter/converter';
 })
 export class AppComponent implements OnInit {
   public steps: Step[] = [];
-  public converters: Converter[] = [];
 
-  constructor(private converterRegistryService: ConverterRegistryService,
-              private inputComponentManagerService: InputComponentManagerService) {
-  }
-
-  convert(step: Step, $event: any): void {
-    step.selectedConverter = this.converterRegistryService.getConverter($event.target.selectedOptions[0].id);
-    this.update(step);
-  }
-
-  update(step: Step): void {
-    const converter: Converter = step.selectedConverter;
-
-    if (converter !== undefined) {
-      const content: string = step.content;
-      let result: string;
-      try {
-        result = converter.convert(content);
-      } catch (error) {
-        if (typeof console === 'object' && typeof console.log === 'function') {
-          console.log(error);
-        }
-        step.message = error.message;
-        step.error = true;
-        result = null;
-      }
-      if (result !== null) {
-        step.message = '';
-        step.error = false;
-        if (result !== '') {
-          const nextComponent: Step = this.inputComponentManagerService.getNext(step);
-          nextComponent.content = result;
-          this.update(nextComponent);
-        }
-      }
-    }
+  constructor(private inputComponentManagerService: InputComponentManagerService) {
   }
 
   ngOnInit(): void {
-    this.converters = this.converterRegistryService.getAllConverters();
     this.steps = this.inputComponentManagerService.getAllComponents();
     this.inputComponentManagerService.getFirst();
   }

src/app/app.module.ts

@@ -6,11 +6,17 @@ import {InputComponentManagerService} from './input-component-manager.service';
 import {NativeLibraryWrapperService} from './native-library-wrapper.service';
 import {FormsModule} from '@angular/forms';
 import {VersionComponent} from './version/version.component';
+import { TextInputFieldComponent } from './text-input-field/text-input-field.component';
+import { ConverterSelectorComponent } from './converter-selector/converter-selector.component';
+import { ErrorMessageComponent } from './error-message/error-message.component';
 
 @NgModule({
   declarations: [
     AppComponent,
-    VersionComponent
+    VersionComponent,
+    TextInputFieldComponent,
+    ConverterSelectorComponent,
+    ErrorMessageComponent
   ],
   imports: [
     BrowserModule,

src/app/converter-registry.service.ts

@@ -36,12 +36,7 @@ export class ConverterRegistryService {
   }
 
   public getConverter(id: string): Converter {
-    for (let i = 0; i < this.converters.length; i++) {
-      if (this.converters[i].getId() === id) {
-        return this.converters[i];
-      }
-    }
-    return undefined;
+    return this.converters.find((converter: Converter): boolean => converter.getId() === id);
   }
 
   private init(): void {
@@ -67,11 +62,11 @@ export class ConverterRegistryService {
   }
 
   private registerConverter(converter: Converter): void {
-    this.converters.forEach((c: Converter) => {
-      if (c.getId() === converter.getId()) {
-        throw new Error('Converter-ID ' + converter.getId() + ' is already registered!');
-      }
-    });
+    // Don't allow duplicate registration of the same converter id
+    if (this.converters.some((c: Converter): boolean => c.getId() === converter.getId())) {
+      throw new Error(`Converter-ID ${converter.getId()} is already registered!`);
+    }
+
     this.converters.push(converter);
   }
 }

src/app/converter-selector/converter-selector.component.html

@@ -0,0 +1,9 @@
+<div [ngClass]="{selectwrapper: true, error: step.error}">
+  <div class="arrow_box">
+    <select class="select" (change)="convert($event)">
+      <option id="undefined">Select conversion ...</option>
+      <option class="option" *ngFor="let c of converters" id="{{c.getId()}}">{{c.getDisplayname()}}
+      </option>
+    </select>
+  </div>
+</div>

src/app/converter-selector/converter-selector.component.scss

@@ -0,0 +1,74 @@
+.selectwrapper {
+  margin: 0 0 1em 0;
+  padding: 0;
+  text-align: center;
+  &.error {
+    > .arrow_box {
+      border-color: red;
+      &:before {
+        border-top-color: red;
+      }
+    }
+    select {
+      color: red;
+    }
+  }
+}
+
+.select {
+  background-color: #fff;
+  border: none;
+  color: #000;
+  font-family: "ABeeZee", sans-serif;
+  margin: 0;
+  padding: 0.5em;
+}
+
+.arrow_box {
+  position: relative;
+  background: #fff;
+  border: 1px solid #aaa;
+  &:focus {
+    border-color: #888;
+  }
+  &:hover {
+    border-color: #333;
+  }
+  &:after, &:before {
+    top: 100%;
+    left: 50%;
+    border: solid transparent;
+    content: " ";
+    height: 0;
+    width: 0;
+    position: absolute;
+    pointer-events: none;
+  }
+  &:after {
+    border-color: rgba(255, 255, 255, 0);
+    border-top-color: #fff;
+    border-width: 1em;
+    margin-left: -1em;
+  }
+  &:before {
+    border-color: rgba(170, 170, 170, 0);
+    border-top-color: #aaa;
+    border-width: calc(1em + 1px);
+    margin-left: calc(-1em - 1px);
+  }
+  &:focus:before {
+    border-color: rgba(136, 136, 136, 0);
+    border-top-color: #888;
+  }
+  &:hover:before {
+    border-color: rgba(51, 51, 51, 0);
+    border-top-color: #333;
+  }
+  .selectwrapper > & {
+    display: inline-block;
+  }
+}
+
+.option {
+  /*    font-family: "ABeeZee", sans-serif;*/
+}

src/app/converter-selector/converter-selector.component.spec.ts

@@ -0,0 +1,93 @@
+import {async, ComponentFixture, TestBed} from '@angular/core/testing';
+
+import {ConverterSelectorComponent} from './converter-selector.component';
+import {Component, ViewChild} from '@angular/core';
+import {Step} from '../step';
+import {TextInputFieldComponent} from '../text-input-field/text-input-field.component';
+import {InputComponentManagerService} from '../input-component-manager.service';
+import {ConverterRegistryService} from '../converter-registry.service';
+import {Converter} from '../converter/converter';
+import createSpyObj = jasmine.createSpyObj;
+import SpyObj = jasmine.SpyObj;
+
+@Component({
+  template: '<app-converter-selector [step]="step" [textInput]="textInputComponent"></app-converter-selector>'
+})
+class TestHostComponent {
+  public step: Step = new Step(42);
+  public textInputComponent: TextInputFieldComponent = new TextInputFieldComponent(inputComponentManagerServiceStub);
+  @ViewChild(ConverterSelectorComponent)
+  public sutComponent: ConverterSelectorComponent;
+}
+
+const inputComponentManagerServiceStub = createSpyObj(['getNext']);
+
+describe('ConverterSelectorComponent', () => {
+  let testHostComponent: TestHostComponent;
+  let testHostFixture: ComponentFixture<TestHostComponent>;
+
+  const converter1: SpyObj<Converter> = createSpyObj(['getId', 'getDisplayname', 'convert']);
+  const converter2: SpyObj<Converter> = createSpyObj(['getId', 'getDisplayname', 'convert']);
+  const converter3: SpyObj<Converter> = createSpyObj(['getId', 'getDisplayname', 'convert']);
+  // converter1.getId.and.returnValue('converter1');
+  converter1.getDisplayname.and.returnValue('Converter 1');
+  // converter2.getId.and.returnValue('converter2');
+  converter2.getDisplayname.and.returnValue('Converter 2');
+  // converter3.getId.and.returnValue('converter3');
+  converter3.getDisplayname.and.returnValue('Converter 3');
+  const converterRegistryServiceStub = createSpyObj(['getAllConverters', 'getConverter']);
+  converterRegistryServiceStub.getAllConverters.and.returnValue([converter1, converter2, converter3]);
+  converterRegistryServiceStub.getConverter.and.returnValue(undefined);
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [
+        ConverterSelectorComponent,
+        TestHostComponent
+      ],
+      providers: [
+        {provide: InputComponentManagerService, useValue: inputComponentManagerServiceStub},
+        {provide: ConverterRegistryService, useValue: converterRegistryServiceStub}
+      ]
+    })
+      .compileComponents();
+  }));
+
+  beforeEach(() => {
+    testHostFixture = TestBed.createComponent(TestHostComponent);
+    testHostComponent = testHostFixture.componentInstance;
+    testHostFixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(testHostComponent.sutComponent).toBeTruthy();
+  });
+
+  it('should update the conversion when the selection changes', () => {
+    // arrange
+    // set next step
+    const nextStep: Step = new Step(99);
+    inputComponentManagerServiceStub.getNext.and.returnValue(nextStep);
+    // set up converter
+    const dummyConverter = createSpyObj(['convert']);
+    dummyConverter.convert.and.returnValue('Converted value');
+    converterRegistryServiceStub.getConverter.and.returnValue(dummyConverter);
+    // create event structure
+    const event = {target: {selectedOptions: [{id: 'The testing converter id'}]}};
+
+    // act
+    testHostComponent.sutComponent.convert(event);
+
+    // assert
+    expect(converterRegistryServiceStub.getConverter).toHaveBeenCalledWith('The testing converter id');
+    expect(nextStep.content).toEqual('Converted value');
+  });
+
+  it('should load available converters upon creation', () => {
+    const converters: Converter[] = testHostComponent.sutComponent.converters;
+    expect(converters.length).toEqual(3);
+    expect(converters[0]).toEqual(converter1);
+    expect(converters[1]).toEqual(converter2);
+    expect(converters[2]).toEqual(converter3);
+  });
+});

src/app/converter-selector/converter-selector.component.ts

@@ -0,0 +1,30 @@
+import {Component, Input, OnInit} from '@angular/core';
+import {Step} from '../step';
+import {Converter} from '../converter/converter';
+import {ConverterRegistryService} from '../converter-registry.service';
+import {TextInputFieldComponent} from '../text-input-field/text-input-field.component';
+
+@Component({
+  selector: 'app-converter-selector',
+  templateUrl: './converter-selector.component.html',
+  styleUrls: ['./converter-selector.component.scss']
+})
+export class ConverterSelectorComponent implements OnInit {
+  @Input()
+  public step: Step;
+  @Input()
+  private textInput: TextInputFieldComponent;
+  public converters: Converter[] = [];
+
+  constructor(private converterRegistryService: ConverterRegistryService) {
+  }
+
+  convert($event: any): void {
+    this.step.selectedConverter = this.converterRegistryService.getConverter($event.target.selectedOptions[0].id);
+    this.textInput.update(this.step);
+  }
+
+  ngOnInit() {
+    this.converters = this.converterRegistryService.getAllConverters();
+  }
+}

src/app/error-message/error-message.component.html

@@ -0,0 +1 @@
+<div class="errormessage" *ngIf="step.error" [innerHTML]="step.message"></div>

src/app/error-message/error-message.component.scss

@@ -0,0 +1,4 @@
+.errormessage {
+  color: red;
+  text-align: center;
+}

src/app/error-message/error-message.component.spec.ts

@@ -0,0 +1,52 @@
+import {async, ComponentFixture, TestBed} from '@angular/core/testing';
+
+import {ErrorMessageComponent} from './error-message.component';
+import {Component, ViewChild} from '@angular/core';
+import {Step} from '../step';
+
+@Component({
+  template: '<app-error-message [step]="step"></app-error-message>'
+})
+class TestHostComponent {
+  public step: Step = new Step(42);
+  @ViewChild(ErrorMessageComponent)
+  public sutComponent: ErrorMessageComponent;
+}
+
+describe('ErrorMessageComponent', () => {
+  let testHostComponent: TestHostComponent;
+  let testHostFixture: ComponentFixture<TestHostComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [
+        ErrorMessageComponent,
+        TestHostComponent
+      ]
+    })
+      .compileComponents();
+  }));
+
+  beforeEach(() => {
+    testHostFixture = TestBed.createComponent(TestHostComponent);
+    testHostComponent = testHostFixture.componentInstance;
+    testHostFixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(testHostComponent.sutComponent).toBeTruthy();
+  });
+
+  it('should display an error message', () => {
+    // arrange
+    testHostComponent.step.error = true;
+    testHostComponent.step.message = 'This is an error message';
+
+    // act
+    testHostFixture.detectChanges();
+
+    // assert
+    expect(testHostComponent.sutComponent.step.error).toBeTruthy();
+    expect(testHostComponent.sutComponent.step.message).toEqual('This is an error message');
+  });
+});

src/app/error-message/error-message.component.ts

@@ -0,0 +1,15 @@
+import {Component, Input} from '@angular/core';
+import {Step} from '../step';
+
+@Component({
+  selector: 'app-error-message',
+  templateUrl: './error-message.component.html',
+  styleUrls: ['./error-message.component.scss']
+})
+export class ErrorMessageComponent {
+  @Input()
+  public step: Step;
+
+  constructor() {
+  }
+}

src/app/text-input-field/text-input-field.component.html

@@ -0,0 +1,4 @@
+<div class="textwrapper arrow_box">
+    <textarea class="textinput" (keyup)="update(step)" placeholder="Please enter your input ..."
+              [(ngModel)]="step.content">{{step.content}}</textarea>
+</div>

src/app/text-input-field/text-input-field.component.scss

@@ -0,0 +1,69 @@
+.textwrapper {
+  margin: 0 0 1em 0;
+  padding: 0 1em 0 0;
+}
+
+.arrow_box {
+  position: relative;
+  background: #fff;
+  border: 1px solid #aaa;
+  &:focus {
+    border-color: #888;
+  }
+  &:hover {
+    border-color: #333;
+  }
+  &:after, &:before {
+    top: 100%;
+    left: 50%;
+    border: solid transparent;
+    content: " ";
+    height: 0;
+    width: 0;
+    position: absolute;
+    pointer-events: none;
+  }
+  &:after {
+    border-color: rgba(255, 255, 255, 0);
+    border-top-color: #fff;
+    border-width: 1em;
+    margin-left: -1em;
+  }
+  &:before {
+    border-color: rgba(170, 170, 170, 0);
+    border-top-color: #aaa;
+    border-width: calc(1em + 1px);
+    margin-left: calc(-1em - 1px);
+  }
+  &:focus:before {
+    border-color: rgba(136, 136, 136, 0);
+    border-top-color: #888;
+  }
+  &:hover:before {
+    border-color: rgba(51, 51, 51, 0);
+    border-top-color: #333;
+  }
+}
+
+.textinput {
+  background-color: #fff;
+  border: none;
+  color: #000;
+  font-family: "Free Monospaced", monospace;
+  height: 10em;
+  margin: 0;
+  padding: 0.5em;
+  resize: vertical;
+  width: 100%;
+  &:focus {
+    border-color: #888;
+  }
+  &:hover {
+    border-color: #333;
+  }
+}
+
+.errormessage {
+  color: red;
+  text-align: center;
+}

src/app/text-input-field/text-input-field.component.spec.ts

@@ -0,0 +1,110 @@
+import {async, ComponentFixture, TestBed} from '@angular/core/testing';
+
+import {TextInputFieldComponent} from './text-input-field.component';
+import {Step} from '../step';
+import {Component, ViewChild} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {InputComponentManagerService} from '../input-component-manager.service';
+import createSpyObj = jasmine.createSpyObj;
+
+@Component({
+  template: '<app-text-input-field [step]="step"></app-text-input-field>'
+})
+class TestHostComponent {
+  public step: Step = new Step(42);
+  @ViewChild(TextInputFieldComponent)
+  public sutComponent: TextInputFieldComponent;
+}
+
+describe('TextInputFieldComponent', () => {
+  let testHostComponent: TestHostComponent;
+  let testHostFixture: ComponentFixture<TestHostComponent>;
+
+  const inputComponentManagerServiceStub = createSpyObj(['getNext']);
+  inputComponentManagerServiceStub.getNext.and.returnValue(undefined);
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [
+        TestHostComponent,
+        TextInputFieldComponent
+      ],
+      imports: [FormsModule],
+      providers: [{provide: InputComponentManagerService, useValue: inputComponentManagerServiceStub}]
+    })
+      .compileComponents();
+  }));
+
+  beforeEach(() => {
+    testHostFixture = TestBed.createComponent(TestHostComponent);
+    testHostComponent = testHostFixture.componentInstance;
+    testHostFixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(testHostComponent.sutComponent).toBeTruthy();
+  });
+
+  it('should not perform an update if no converter is selected', () => {
+    // arrange
+    const step: Step = testHostComponent.step;
+    step.content = 'Don\'t you change me!';
+    step.error = false;
+    step.message = 'There be no message.';
+
+    // act
+    testHostComponent.sutComponent.update(step);
+
+    // assert
+    expect(step.content).toEqual('Don\'t you change me!');
+    expect(step.error).toBeFalsy();
+    expect(step.message).toEqual('There be no message.');
+  });
+
+  it('should set the error flag if the conversion fails', () => {
+    // arrange
+    const step: Step = testHostComponent.step;
+    step.content = 'Don\'t you change me!';
+    step.error = false;
+    step.message = 'There be no message.';
+    step.selectedConverter = {
+      getId: () => 'testConverter',
+      convert: () => {
+        throw new Error('Test error');
+      },
+      getDisplayname: () => 'Testing converter'
+    };
+
+    // act
+    testHostComponent.sutComponent.update(step);
+
+    // assert
+    expect(step.content).toEqual('Don\'t you change me!');
+    expect(step.error).toBeTruthy();
+    expect(step.message).toEqual('Test error');
+  });
+
+  it('should correctly convert valid input', () => {
+    // arrange
+    const nextStep: Step = new Step(82);
+    inputComponentManagerServiceStub.getNext.and.returnValue(nextStep);
+    const step: Step = testHostComponent.step;
+    step.content = 'Don\'t you change me!';
+    step.error = true;
+    step.message = 'There be no message.';
+    step.selectedConverter = {
+      getId: () => 'testConverter',
+      convert: () => 'The Converted Result',
+      getDisplayname: () => 'Testing converter'
+    };
+
+    // act
+    testHostComponent.sutComponent.update(step);
+
+    // assert
+    expect(step.content).toEqual('Don\'t you change me!');
+    expect(step.error).toBeFalsy();
+    expect(step.message).toEqual('');
+    expect(nextStep.content).toEqual('The Converted Result');
+  });
+});

src/app/text-input-field/text-input-field.component.ts

@@ -0,0 +1,45 @@
+import {Component, Input} from '@angular/core';
+import {Step} from '../step';
+import {Converter} from '../converter/converter';
+import {InputComponentManagerService} from '../input-component-manager.service';
+
+@Component({
+  selector: 'app-text-input-field',
+  templateUrl: './text-input-field.component.html',
+  styleUrls: ['./text-input-field.component.scss']
+})
+export class TextInputFieldComponent {
+  @Input()
+  public step: Step;
+
+  constructor(private inputComponentManagerService: InputComponentManagerService) {
+  }
+
+  update(step: Step): void {
+    const converter: Converter = step.selectedConverter;
+
+    if (converter !== undefined) {
+      const content: string = step.content;
+      let result: string;
+      try {
+        result = converter.convert(content);
+      } catch (error) {
+        if (typeof console === 'object' && typeof console.log === 'function') {
+          console.log(error);
+        }
+        step.message = error.message;
+        step.error = true;
+        result = null;
+      }
+      if (result !== null) {
+        step.message = '';
+        step.error = false;
+        if (result !== '') {
+          const nextComponent: Step = this.inputComponentManagerService.getNext(step);
+          nextComponent.content = result;
+          this.update(nextComponent);
+        }
+      }
+    }
+  }
+}