[vscode] implement proposed.textEditorDiffInformation API

Resolves GH-16278

Contributed on behalf of STMicroelectronics

Author: ndoschek

packages/plugin-ext/src/plugin/plugin-context.ts

@@ -241,7 +241,8 @@ import {
     TerminalCompletionList,
     McpHttpServerDefinition,
     McpStdioServerDefinition,
-    InteractiveWindowInput
+    InteractiveWindowInput,
+    TextEditorChangeKind
 } from './types-impl';
 import { AuthenticationExtImpl } from './authentication-ext';
 import { SymbolKind } from '../common/plugin-api-rpc-model';
@@ -478,6 +479,9 @@ export function createAPIFactory(
             onDidChangeTextEditorSelection(listener, thisArg?, disposables?) {
                 return editors.onDidChangeTextEditorSelection(listener, thisArg, disposables);
             },
+            onDidChangeTextEditorDiffInformation(listener, thisArg?, disposables?) {
+                return editors.onDidChangeTextEditorDiffInformation(listener, thisArg, disposables);
+            },
             onDidChangeTextEditorOptions(listener, thisArg?, disposables?) {
                 return editors.onDidChangeTextEditorOptions(listener, thisArg, disposables);
             },
@@ -1621,6 +1625,7 @@ export function createAPIFactory(
             McpHttpServerDefinition,
             McpStdioServerDefinition,
             TabInputInteractiveWindow: InteractiveWindowInput,
+            TextEditorChangeKind
         };
     };
 }

packages/plugin-ext/src/plugin/text-editor.ts

@@ -27,6 +27,8 @@ export class TextEditorExt implements theia.TextEditor {
     private _viewColumn: theia.ViewColumn | undefined;
     private _document: DocumentDataExt;
     private _options: TextEditorOptionsExt;
+    private _diffInformation: theia.TextEditorDiffInformation[] | undefined;
+
     private disposed = false;
     constructor(
         private readonly proxy: TextEditorsMain,
@@ -278,6 +280,15 @@ export class TextEditorExt implements theia.TextEditor {
     getDiffInformation(): Promise<theia.LineChange[]> {
         return this.proxy.$getDiffInformation(this.id);
     }
+
+    _acceptDiffInformation(diffInformation: theia.TextEditorDiffInformation[] | undefined): void {
+        // ok(!this._disposed);
+        this._diffInformation = diffInformation;
+    }
+
+    get diffInformation(): theia.TextEditorDiffInformation[] | undefined {
+        return this._diffInformation;
+    }
 }
 
 export class TextEditorOptionsExt implements theia.TextEditorOptions {

packages/plugin-ext/src/plugin/text-editors.ts

@@ -21,21 +21,23 @@ import { Emitter, Event } from '@theia/core/lib/common/event';
 import { EditorsAndDocumentsExtImpl } from './editors-and-documents';
 import { TextEditorExt } from './text-editor';
 import * as Converters from './type-converters';
-import { TextEditorSelectionChangeKind, URI } from './types-impl';
+import { TextEditorChangeKind, TextEditorSelectionChangeKind, URI } from './types-impl';
 import { IdGenerator } from '../common/id-generator';
 
 export class TextEditorsExtImpl implements TextEditorsExt {
     private readonly _onDidChangeTextEditorSelection = new Emitter<theia.TextEditorSelectionChangeEvent>();
     private readonly _onDidChangeTextEditorOptions = new Emitter<theia.TextEditorOptionsChangeEvent>();
     private readonly _onDidChangeTextEditorVisibleRanges = new Emitter<theia.TextEditorVisibleRangesChangeEvent>();
     private readonly _onDidChangeTextEditorViewColumn = new Emitter<theia.TextEditorViewColumnChangeEvent>();
+    private readonly _onDidChangeTextEditorDiffInformation = new Emitter<theia.TextEditorDiffInformationChangeEvent>();
     private readonly _onDidChangeActiveTextEditor = new Emitter<theia.TextEditor | undefined>();
     private readonly _onDidChangeVisibleTextEditors = new Emitter<theia.TextEditor[]>();
 
     readonly onDidChangeTextEditorSelection: Event<theia.TextEditorSelectionChangeEvent> = this._onDidChangeTextEditorSelection.event;
     readonly onDidChangeTextEditorOptions = this._onDidChangeTextEditorOptions.event;
     readonly onDidChangeTextEditorVisibleRanges = this._onDidChangeTextEditorVisibleRanges.event;
     readonly onDidChangeTextEditorViewColumn = this._onDidChangeTextEditorViewColumn.event;
+    readonly onDidChangeTextEditorDiffInformation = this._onDidChangeTextEditorDiffInformation.event;
     readonly onDidChangeActiveTextEditor = this._onDidChangeActiveTextEditor.event;
     readonly onDidChangeVisibleTextEditors = this._onDidChangeVisibleTextEditors.event;
 
@@ -118,6 +120,73 @@ export class TextEditorsExtImpl implements TextEditorsExt {
         return activeEditor.getDiffInformation();
     }
 
+    $acceptEditorDiffInformation(id: string, diffInformation: theia.TextEditorDiffInformation[] | undefined): void {
+        const textEditor = this.editorsAndDocuments.getEditor(id);
+        if (!textEditor) {
+            throw new Error('unknown text editor');
+        }
+
+        if (!diffInformation) {
+            textEditor._acceptDiffInformation(undefined);
+            this._onDidChangeTextEditorDiffInformation.fire({
+                textEditor: textEditor,
+                diffInformation: undefined
+            });
+            return;
+        }
+
+        const that = this;
+        const result = diffInformation.map(diff => {
+            const original = URI.revive(diff.original);
+            const modified = URI.revive(diff.modified);
+
+            const changes = diff.changes.map(change => {
+                const originalStartLineNumber = change.original.startLineNumber;
+                const originalEndLineNumberExclusive = change.original.endLineNumberExclusive;
+                const modifiedStartLineNumber = change.modified.startLineNumber;
+                const modifiedEndLineNumberExclusive = change.modified.endLineNumberExclusive;
+
+                let kind: TextEditorChangeKind;
+                if (change.original.startLineNumber === originalEndLineNumberExclusive) {
+                    kind = TextEditorChangeKind.Addition;
+                } else if (modifiedStartLineNumber === modifiedEndLineNumberExclusive) {
+                    kind = TextEditorChangeKind.Deletion;
+                } else {
+                    kind = TextEditorChangeKind.Modification;
+                }
+
+                return {
+                    original: {
+                        startLineNumber: originalStartLineNumber,
+                        endLineNumberExclusive: originalEndLineNumberExclusive
+                    },
+                    modified: {
+                        startLineNumber: modifiedStartLineNumber,
+                        endLineNumberExclusive: modifiedEndLineNumberExclusive
+                    },
+                    kind
+                } satisfies theia.TextEditorChange;
+            });
+
+            return Object.freeze({
+                documentVersion: diff.documentVersion,
+                original,
+                modified,
+                changes,
+                get isStale(): boolean {
+                    const document = that.editorsAndDocuments.getDocument(modified.toString());
+                    return document?.document.version !== diff.documentVersion;
+                }
+            });
+        });
+
+        textEditor._acceptDiffInformation(result);
+        this._onDidChangeTextEditorDiffInformation.fire({
+            textEditor: textEditor,
+            diffInformation: result
+        });
+    }
+
     getVisibleTextEditors(): theia.TextEditor[] {
         return this.editorsAndDocuments.allEditors();
     }

packages/plugin-ext/src/plugin/types-impl.ts

@@ -4320,3 +4320,40 @@ export class McpHttpServerDefinition {
  */
 export type McpServerDefinition = McpStdioServerDefinition | McpHttpServerDefinition;
 
+// #region textEditorDiffInformation
+
+export enum TextEditorChangeKind {
+    Addition = 1,
+    Deletion = 2,
+    Modification = 3
+}
+
+export interface TextEditorLineRange {
+    readonly startLineNumber: number;
+    readonly endLineNumberExclusive: number;
+}
+
+export interface TextEditorChange {
+    readonly original: TextEditorLineRange;
+    readonly modified: TextEditorLineRange;
+    readonly kind: TextEditorChangeKind;
+}
+
+export interface TextEditorDiffInformation {
+    readonly documentVersion: number;
+    readonly original: theia.Uri | undefined;
+    readonly modified: theia.Uri;
+    readonly changes: readonly TextEditorChange[];
+    readonly isStale: boolean;
+}
+
+export interface TextEditorDiffInformationChangeEvent {
+    readonly textEditor: TextEditor;
+    readonly diffInformation: TextEditorDiffInformation[] | undefined;
+}
+
+export interface TextEditor {
+    readonly diffInformation: TextEditorDiffInformation[] | undefined;
+}
+
+// #endregion

packages/plugin/src/theia.d.ts

@@ -45,6 +45,7 @@ import './theia.proposed.scmValidation';
 import './theia.proposed.shareProvider';
 import './theia.proposed.terminalCompletionProvider';
 import './theia.proposed.terminalQuickFixProvider';
+import './theia.proposed.textEditorDiffInformation';
 import './theia.proposed.textSearchProvider';
 import './theia.proposed.timeline';
 

packages/plugin/src/theia.proposed.textEditorDiffInformation.d.ts

@@ -0,0 +1,64 @@
+// *****************************************************************************
+// Copyright (C) 2025 STMicroelectronics and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+// code copied and modified from https://github.com/microsoft/vscode/blob/1.103.2/src/vscode-dts/vscode.proposed.textEditorDiffInformation.d.ts
+
+declare module '@theia/plugin' {
+    // https://github.com/microsoft/vscode/issues/84899
+
+    export enum TextEditorChangeKind {
+        Addition = 1,
+        Deletion = 2,
+        Modification = 3
+    }
+
+    export interface TextEditorLineRange {
+        readonly startLineNumber: number;
+        readonly endLineNumberExclusive: number;
+    }
+
+    export interface TextEditorChange {
+        readonly original: TextEditorLineRange;
+        readonly modified: TextEditorLineRange;
+        readonly kind: TextEditorChangeKind;
+    }
+
+    export interface TextEditorDiffInformation {
+        readonly documentVersion: number;
+        readonly original: Uri | undefined;
+        readonly modified: Uri;
+        readonly changes: readonly TextEditorChange[];
+        readonly isStale: boolean;
+    }
+
+    export interface TextEditorDiffInformationChangeEvent {
+        readonly textEditor: TextEditor;
+        readonly diffInformation: TextEditorDiffInformation[] | undefined;
+    }
+
+    export interface TextEditor {
+        readonly diffInformation: TextEditorDiffInformation[] | undefined;
+    }
+
+    export namespace window {
+        export const onDidChangeTextEditorDiffInformation: Event<TextEditorDiffInformationChangeEvent>;
+    }
+
+}