Conform more of the codebase to strictNullChecks (#10573)

* Conform more of the codebase to `strictNullChecks`

* Iterate

src/editor/autocomplete.ts

@@ -28,7 +28,7 @@ export interface ICallback {
 }
 
 export type UpdateCallback = (data: ICallback) => void;
-export type GetAutocompleterComponent = () => Autocomplete;
+export type GetAutocompleterComponent = () => Autocomplete | null;
 export type UpdateQuery = (test: string) => Promise<void>;
 
 export default class AutocompleteWrapperModel {
@@ -42,7 +42,7 @@ export default class AutocompleteWrapperModel {
     ) {}
 
     public onEscape(e: KeyboardEvent): void {
-        this.getAutocompleterComponent().onEscape(e);
+        this.getAutocompleterComponent()?.onEscape(e);
     }
 
     public close(): void {
@@ -50,16 +50,16 @@ export default class AutocompleteWrapperModel {
     }
 
     public hasSelection(): boolean {
-        return this.getAutocompleterComponent().hasSelection();
+        return !!this.getAutocompleterComponent()?.hasSelection();
     }
 
     public hasCompletions(): boolean {
         const ac = this.getAutocompleterComponent();
-        return ac && ac.countCompletions() > 0;
+        return !!ac && ac.countCompletions() > 0;
     }
 
     public confirmCompletion(): void {
-        this.getAutocompleterComponent().onConfirmCompletion();
+        this.getAutocompleterComponent()?.onConfirmCompletion();
         this.updateCallback({ close: true });
     }
 
@@ -68,18 +68,18 @@ export default class AutocompleteWrapperModel {
      */
     public async startSelection(): Promise<void> {
         const acComponent = this.getAutocompleterComponent();
-        if (acComponent.countCompletions() === 0) {
+        if (acComponent && acComponent.countCompletions() === 0) {
             // Force completions to show for the text currently entered
             await acComponent.forceComplete();
         }
     }
 
     public selectPreviousSelection(): void {
-        this.getAutocompleterComponent().moveSelection(-1);
+        this.getAutocompleterComponent()?.moveSelection(-1);
     }
 
     public selectNextSelection(): void {
-        this.getAutocompleterComponent().moveSelection(+1);
+        this.getAutocompleterComponent()?.moveSelection(+1);
     }
 
     public onPartUpdate(part: Part, pos: DocumentPosition): Promise<void> {

src/editor/model.ts

@@ -44,7 +44,7 @@ import { Caret } from "./caret";
  * @return the caret position
  */
 
-type TransformCallback = (caretPosition: DocumentPosition, inputType: string, diff: IDiff) => number | void;
+type TransformCallback = (caretPosition: DocumentPosition, inputType: string | undefined, diff: IDiff) => number | void;
 type UpdateCallback = (caret?: Caret, inputType?: string, diff?: IDiff) => void;
 type ManualTransformCallback = () => Caret;
 
@@ -151,7 +151,7 @@ export default class EditorModel {
         return this._parts.map((p) => p.serialize());
     }
 
-    private diff(newValue: string, inputType: string, caret: DocumentOffset): IDiff {
+    private diff(newValue: string, inputType: string | undefined, caret: DocumentOffset): IDiff {
         const previousValue = this.parts.reduce((text, p) => text + p.text, "");
         // can't use caret position with drag and drop
         if (inputType === "deleteByDrag") {
@@ -196,7 +196,7 @@ export default class EditorModel {
         return newTextLength;
     }
 
-    public update(newValue: string, inputType: string, caret: DocumentOffset): Promise<void> {
+    public update(newValue: string, inputType: string | undefined, caret: DocumentOffset): Promise<void> {
         const diff = this.diff(newValue, inputType, caret);
         const position = this.positionForOffset(diff.at || 0, caret.atNodeEnd);
         let removedOffsetDecrease = 0;
@@ -220,7 +220,7 @@ export default class EditorModel {
         return acPromise;
     }
 
-    private getTransformAddedLen(newPosition: DocumentPosition, inputType: string, diff: IDiff): number {
+    private getTransformAddedLen(newPosition: DocumentPosition, inputType: string | undefined, diff: IDiff): number {
         const result = this.transformCallback?.(newPosition, inputType, diff);
         return Number.isFinite(result) ? (result as number) : 0;
     }
@@ -360,7 +360,7 @@ export default class EditorModel {
      * @return {Number} how far from position (in characters) the insertion ended.
      * This can be more than the length of `str` when crossing non-editable parts, which are skipped.
      */
-    private addText(pos: IPosition, str: string, inputType: string): number {
+    private addText(pos: IPosition, str: string, inputType: string | undefined): number {
         let { index } = pos;
         const { offset } = pos;
         let addLen = str.length;

src/editor/parts.ts

@@ -65,8 +65,8 @@ interface IBasePart {
     serialize(): SerializedPart;
     remove(offset: number, len: number): string | undefined;
     split(offset: number): IBasePart;
-    validateAndInsert(offset: number, str: string, inputType: string): boolean;
-    appendUntilRejected(str: string, inputType: string): string | undefined;
+    validateAndInsert(offset: number, str: string, inputType: string | undefined): boolean;
+    appendUntilRejected(str: string, inputType: string | undefined): string | undefined;
     updateDOMNode(node: Node): void;
     canUpdateDOMNode(node: Node): boolean;
     toDOMNode(): Node;