Fix jump tracking when document changed externally

Previously `git checkout` would mess up your jumps

Author: J-Fields

extensionBase.ts

@@ -144,20 +144,13 @@ export async function activate(context: vscode.ExtensionContext, handleLocal: bo
       Logger.trace(`\t-${x.rangeLength}, +'${x.text}'`);
     }
 
-    if (event.contentChanges.length === 1) {
-      const change = event.contentChanges[0];
-
-      const anyLinesDeleted = change.range.start.line !== change.range.end.line;
-
-      if (anyLinesDeleted && change.text === '') {
+    for (const change of event.contentChanges) {
+      if (change.rangeLength > 0) {
         globalState.jumpTracker.handleTextDeleted(event.document, change.range);
-      } else if (!anyLinesDeleted && change.text.includes('\n')) {
-        globalState.jumpTracker.handleTextAdded(event.document, change.range, change.text);
-      } else {
-        // TODO: What to do here?
       }
-    } else {
-      // TODO: In this case, we should probably loop over the content changes...
+      if (change.text.length > 0) {
+        globalState.jumpTracker.handleTextAdded(event.document, change.range.start, change.text);
+      }
     }
 
     const mh = ModeHandlerMap.get(event.document.uri);

src/jumps/jumpTracker.ts

@@ -237,18 +237,25 @@ export class JumpTracker {
    * Update existing jumps when lines were added to a document.
    *
    * @param document - Document that was changed, typically a vscode.TextDocument.
-   * @param range - Location where the text was added.
+   * @param position - Location where the text was added.
    * @param text - Text containing one or more newline characters.
    */
-  public handleTextAdded(document: { fileName: string }, range: vscode.Range, text: string): void {
+  public handleTextAdded(
+    document: { fileName: string },
+    position: vscode.Position,
+    text: string,
+  ): void {
     // Get distance from newlines in the text added.
     // Unlike handleTextDeleted, the range parameter distance between start/end is generally zero,
     // just showing where the text was added.
     const distance = text.split('').filter((c) => c === '\n').length;
+    if (distance === 0) {
+      return;
+    }
 
     for (const [i, jump] of this._jumps.entries()) {
       const jumpIsAfterAddedText =
-        jump.fileName === document.fileName && jump.position.line > range.start.line;
+        jump.fileName === document.fileName && jump.position.line > position.line;
 
       if (jumpIsAfterAddedText) {
         const newPosition = new Position(jump.position.line + distance, jump.position.character);

test/jumpTracker.test.ts

@@ -440,5 +440,7 @@ suite('Record and navigate jumps', () => {
         jumps: ['start', 'end'],
       });
     });
+
+    // TODO: Test that jumps are adjusted properly when document is modified externally
   });
 });