update dependencies, apply new lint rules

package.json

@@ -356,13 +356,13 @@
     }
   },
   "devDependencies": {
-    "@parcel/transformer-typescript-tsc": "^2.0.0-nightly.487",
-    "@types/diff": "^4.0.2",
+    "@parcel/transformer-typescript-tsc": "^2.0.0-nightly.576",
+    "@types/diff": "^5.0.0",
     "@types/glob": "^7.1.3",
     "@types/mocha": "^8.0.3",
     "@types/node": "^14.6.2",
     "@types/vscode": "^1.48.0",
-    "@types/which": "^1.3.2",
+    "@types/which": "^2.0.0",
     "@typescript-eslint/eslint-plugin": "^4.0.1",
     "@typescript-eslint/parser": "^4.0.1",
     "cpy-cli": "^3.1.1",
@@ -372,11 +372,11 @@
     "eslint-plugin-eslint-comments": "^3.2.0",
     "eslint-plugin-prettier": "^3.1.4",
     "eslint-plugin-promise": "^4.2.1",
-    "eslint-plugin-unicorn": "^24.0.0",
+    "eslint-plugin-unicorn": "^27.0.0",
     "glob": "^7.1.6",
     "husky": "^4.2.5",
     "mocha": "^8.1.3",
-    "node-pty": "^0.9.0",
+    "node-pty": "^0.10.0",
     "parcel": "^2.0.0-beta.1",
     "prettier": "^2.1.1",
     "ts-node": "^9.0.0",

src/mergetoolUI.ts

@@ -318,7 +318,7 @@ export class MergetoolUI {
     }
     this.disposing = true;
     this.disposeStatusBarItems();
-    this.registeredDisposables.forEach((item) => void item?.dispose());
+    for (const item of this.registeredDisposables) void item?.dispose();
     this.registeredDisposables = new Set();
     void this.disposeProcessManager();
   }
@@ -586,8 +586,13 @@ export class MergetoolUI {
     return true;
   }
 
-  private disposeStatusBarItems() {
-    this.statusBarItems?.forEach((item) => item.dispose());
+  private disposeStatusBarItems(): void {
+    if (this.statusBarItems === undefined) {
+      return;
+    }
+    for (const item of this.statusBarItems) {
+      item.dispose();
+    }
     this.statusBarItems = undefined;
   }
 
@@ -610,9 +615,7 @@ export class MergetoolUI {
             14,
             nextMergeStepCommandID,
             "Go to next conflict, next file, or commit message"
-          )
-        );
-        this.statusBarItems.push(
+          ),
           this.createStatusBarItem(
             "$(live-share)" + (showLabel ? " Skip file" : ""),
             13,

src/scrollSynchronizer.ts

@@ -19,9 +19,9 @@ export class ScrollSynchronizer implements Disposable {
     syncMethod?: ScrollSyncMethod,
     mappedIntervalRelativeSize?: number
   ): Promise<ScrollSynchronizer> {
-    const scrollIgnoreCounts = new Array<number>(editors.length).fill(
-      synchronizationSourceOnStartIndex === undefined ? 0 : 1
-    );
+    const scrollIgnoreCounts = Array.from<number>({
+      length: editors.length,
+    }).fill(synchronizationSourceOnStartIndex === undefined ? 0 : 1);
     if (synchronizationSourceOnStartIndex !== undefined) {
       scrollIgnoreCounts[synchronizationSourceOnStartIndex] = 0;
     }
@@ -85,12 +85,18 @@ export class ScrollSynchronizer implements Disposable {
     private readonly centerPosCorrection = +0.5,
     private readonly eventDecayPerSec = 0.25
   ) {
-    this.editorLinesCache = new Array<undefined>(editors.length).fill(
-      undefined
-    );
-    this.scrollIgnoreDates = new Array<number>(editors.length).fill(0);
-    this.selectionIgnoreCounts = new Array<number>(editors.length).fill(0);
-    this.selectionIgnoreDates = new Array<number>(editors.length).fill(0);
+    this.editorLinesCache = Array.from<undefined>({
+      length: editors.length,
+    }).fill(undefined);
+    this.scrollIgnoreDates = Array.from<number>({
+      length: editors.length,
+    }).fill(0);
+    this.selectionIgnoreCounts = Array.from<number>({
+      length: editors.length,
+    }).fill(0);
+    this.selectionIgnoreDates = Array.from<number>({
+      length: editors.length,
+    }).fill(0);
     this.documents = this.editors.map((editor) => editor.document);
     this.mappedWeight1 = (1 - mappedIntervalRelativeSize) / 2;
     this.mappedWeight0 = 1 - this.mappedWeight1;
@@ -477,7 +483,7 @@ export class ScrollSynchronizer implements Disposable {
     if (mapper === undefined) {
       return undefined;
     }
-    // eslint-disable-next-line unicorn/no-fn-reference-in-iterator
+    // eslint-disable-next-line unicorn/no-array-callback-reference
     return mapper.map(position);
   }
 }

test/mochaTest.ts

@@ -8,7 +8,7 @@ export function runMochaTests(
 ): Promise<void> {
   // Create the mocha test
   const debug = /--debug|--inspect/.test(
-    [process.argv.concat(process.execArgv)].join(" ")
+    [...process.argv, ...process.execArgv].join(" ")
   );
   const mocha = new Mocha({
     ui: "tdd",
@@ -25,7 +25,9 @@ export function runMochaTests(
       }
 
       // Add files to the test suite
-      files.forEach((f) => mocha.addFile(path.resolve(testsRoot, f)));
+      for (const f of files) {
+        mocha.addFile(path.resolve(testsRoot, f));
+      }
 
       try {
         // Run the mocha test

test/suite/unitTest.systemTest/suite/diffLineMapper.test.ts

@@ -32,7 +32,7 @@ suite("DiffLineMapper", () => {
         testCase.old.split(""),
         testCase.new.split("")
       );
-      // eslint-disable-next-line unicorn/no-fn-reference-in-iterator
+      // eslint-disable-next-line unicorn/no-array-callback-reference
       const actual = sut.map(testCase.from);
       assert.strictEqual(
         actual,