refactor: Simplify stateField type

Fixes #20

src/commands.ts

@@ -8,9 +8,8 @@ export function acceptSuggestionCommand(view: EditorView) {
   // We delete the ghost text and insert the suggestion.
   // We also set the cursor to the end of the suggestion.
   const stateField = view.state.field(completionDecoration)!;
-  const ghostTexts = stateField.ghostTexts;
 
-  if (!ghostTexts) {
+  if (!stateField) {
     return false;
   }
 
@@ -51,9 +50,8 @@ export function acceptSuggestionCommand(view: EditorView) {
 export function rejectSuggestionCommand(view: EditorView) {
   // We delete the suggestion, then carry through with the original keypress
   const stateField = view.state.field(completionDecoration)!;
-  const ghostTexts = stateField.ghostTexts;
 
-  if (!ghostTexts?.length) {
+  if (!stateField) {
     return false;
   }
 
@@ -76,9 +74,9 @@ export function rejectSuggestionCommand(view: EditorView) {
 // TODO: this isn't full reimplemented yet.
 export function sameKeyCommand(view: EditorView, key: string) {
   // When we type a key that is the same as the first letter of the suggestion, we delete the first letter of the suggestion and carry through with the original keypress
-  const ghostTexts = view.state.field(completionDecoration)!.ghostTexts;
+  const stateField = view.state.field(completionDecoration);
 
-  if (!ghostTexts || !ghostTexts.length) {
+  if (!stateField) {
     return false;
   }
 

src/completionDecoration.ts

@@ -11,24 +11,18 @@ const ghostMark = Decoration.mark({ class: "cm-ghostText" });
 
 export const completionDecoration = StateField.define<CompletionState>({
   create(_state: EditorState) {
-    return { ghostTexts: null };
+    return null;
   },
   update(state: CompletionState, transaction: Transaction) {
     for (const effect of transaction.effects) {
       if (effect.is(addSuggestions)) {
         // NOTE: here we're adjusting the decoration range
         // to refer to locations in the document _after_ we've
         // inserted the text.
-        let decorationOffset = 0;
         const decorations = Decoration.set(
           effect.value.suggestions.map((suggestion) => {
-            const endGhostText =
-              suggestion.startPos + suggestion.displayText.length;
-            let range = ghostMark.range(
-              decorationOffset + suggestion.startPos,
-              decorationOffset + endGhostText,
-            );
-            decorationOffset += suggestion.displayText.length;
+            console.log(suggestion.startPos, suggestion.endPos);
+            let range = ghostMark.range(suggestion.startPos, suggestion.endPos);
             return range;
           }),
         );
@@ -37,36 +31,18 @@ export const completionDecoration = StateField.define<CompletionState>({
         return {
           decorations,
           reverseChangeSet: effect.value.reverseChangeSet,
-          ghostTexts: effect.value.suggestions.map((suggestion) => {
-            const endGhostText =
-              suggestion.cursorPos + suggestion.displayText.length;
-            return {
-              text: suggestion.text,
-              displayText: suggestion.text,
-              startPos: suggestion.startPos,
-              endPos: suggestion.endPos,
-              decorations,
-              // TODO: what's the difference between this
-              // and startPos?
-              displayPos: suggestion.cursorPos,
-              endReplacement: suggestion.endReplacement,
-              endGhostText,
-            };
-          }),
         };
       } else if (effect.is(acceptSuggestion)) {
-        if (state.ghostTexts) {
-          return { ghostTexts: null };
-        }
+        return null;
       } else if (effect.is(clearSuggestion)) {
-        return { ghostTexts: null };
+        return null;
       }
     }
 
     return state;
   },
   provide: (field) =>
     EditorView.decorations.from(field, (value) => {
-      return value.decorations || Decoration.none;
+      return value?.decorations || Decoration.none;
     }),
 });

src/completionRequester.ts

@@ -39,7 +39,7 @@ function shouldIgnoreUpdate(update: ViewUpdate) {
   if (!update.view.hasFocus) return true;
 
   // contains ghost text
-  if (update.state.field(completionDecoration).ghostTexts != null) return true;
+  if (update.state.field(completionDecoration)) return true;
 
   // is autocompleting
   if (completionStatus(update.state) === "active") return true;
@@ -121,18 +121,26 @@ export function completionRequester() {
 
         const reverseChangeSet = insertChangeSet.invert(state.doc);
 
+        let combinedOffset = 0;
         update.view.dispatch({
           changes: insertChangeSet,
           effects: addSuggestions.of({
             reverseChangeSet,
-            suggestions: simplifyCompletions(completionResult).map((part) => ({
-              displayText: part.text,
-              endReplacement: 0, // "",
-              text: part.text,
-              cursorPos: pos,
-              startPos: Number(part.offset),
-              endPos: Number(part.offset) + part.text.length,
-            })),
+            suggestions: simplifyCompletions(completionResult).map((part) => {
+              try {
+                return {
+                  displayText: part.text,
+                  endReplacement: 0, // "",
+                  text: part.text,
+                  cursorPos: pos,
+                  startPos: combinedOffset + Number(part.offset),
+                  endPos:
+                    combinedOffset + Number(part.offset) + part.text.length,
+                };
+              } finally {
+                combinedOffset += part.text.length;
+              }
+            }),
           }),
           annotations: [
             copilotIgnore.of(null),

src/plugin.ts

@@ -14,12 +14,11 @@ import { copilotIgnore } from "./annotations.js";
 function isDecorationClicked(view: EditorView) {
   let inRange = false;
   const head = view.state.selection.asSingle().ranges.at(0)?.head;
-  if (head !== undefined) {
-    view.state
-      .field(completionDecoration)
-      .decorations?.between(head, head, () => {
-        inRange = true;
-      });
+  const stateField = view.state.field(completionDecoration);
+  if (head !== undefined && stateField) {
+    stateField.decorations?.between(head, head, () => {
+      inRange = true;
+    });
     return inRange;
   }
   return false;

src/types.ts

@@ -10,11 +10,10 @@ export interface Suggestion {
   endReplacement: number;
 }
 
-export interface CompletionState {
-  ghostTexts: GhostText[] | null;
-  reverseChangeSet?: ChangeSet;
-  decorations?: DecorationSet;
-}
+export type CompletionState = null | {
+  reverseChangeSet: ChangeSet;
+  decorations: DecorationSet;
+};
 
 export interface GhostText {
   text: string;