diff --git a/src/goDocumentSymbols.ts b/src/goDocumentSymbols.ts
index 5809237..1aa814e 100644
--- a/src/goDocumentSymbols.ts
+++ b/src/goDocumentSymbols.ts
@@ -25,6 +25,10 @@
 	constructor(private readonly goCtx: GoExtensionContext, private includeImports?: boolean) {}
 
 	public async provideDocumentSymbols(document: vscode.TextDocument): Promise<vscode.DocumentSymbol[]> {
+		// TODO(suzmue): consider providing an interface for providing document symbols that only requires
+		// the URI. Getting a TextDocument from a filename requires opening the file, which can lead to
+		// files being opened that were not requested by the user in order to get information that we just
+		// need the URI to access.
 		if (typeof this.includeImports !== 'boolean') {
 			const gotoSymbolConfig = getGoConfig(document.uri)['gotoSymbol'];
 			this.includeImports = gotoSymbolConfig ? gotoSymbolConfig['includeImports'] : false;
diff --git a/src/goTest/explore.ts b/src/goTest/explore.ts
index 5493b0e..a9a75fe 100644
--- a/src/goTest/explore.ts
+++ b/src/goTest/explore.ts
@@ -258,7 +258,12 @@
 	}
 
 	protected async didCreateFile(file: Uri) {
-		await this.documentUpdate(await this.workspace.openTextDocument(file));
+		// Do not use openTextDocument to get the TextDocument for file,
+		// since this sends a didOpen text document notification to gopls,
+		// leading to spurious diagnostics from gopls:
+		// https://github.com/golang/vscode-go/issues/2570
+		// Instead, get the test item for this file only.
+		await this.resolver.getFile(file);
 	}
 
 	protected async didDeleteFile(file: Uri) {
diff --git a/src/goTest/resolve.ts b/src/goTest/resolve.ts
index 2b4d93c..48c38bf 100644
--- a/src/goTest/resolve.ts
+++ b/src/goTest/resolve.ts
@@ -233,6 +233,21 @@
 		vscode.commands.executeCommand('setContext', 'go.tests', items);
 	}
 
+	// Retrieve or create an item for a Go file.
+	public async getFile(uri: Uri): Promise<TestItem> {
+		const dir = path.dirname(uri.path);
+		const pkg = await this.getPackage(uri.with({ path: dir, query: '', fragment: '' }));
+		const existing = this.getItem(pkg, uri, 'file');
+		if (existing) {
+			return existing;
+		}
+
+		const label = path.basename(uri.path);
+		const item = this.getOrCreateItem(pkg, label, uri, 'file');
+		item.canResolveChildren = true;
+		return item;
+	}
+
 	/* ***** Private ***** */
 
 	private shouldSetRange(item: TestItem): boolean {
@@ -375,21 +390,6 @@
 		return item;
 	}
 
-	// Retrieve or create an item for a Go file.
-	private async getFile(uri: Uri): Promise<TestItem> {
-		const dir = path.dirname(uri.path);
-		const pkg = await this.getPackage(uri.with({ path: dir, query: '', fragment: '' }));
-		const existing = this.getItem(pkg, uri, 'file');
-		if (existing) {
-			return existing;
-		}
-
-		const label = path.basename(uri.path);
-		const item = this.getOrCreateItem(pkg, label, uri, 'file');
-		item.canResolveChildren = true;
-		return item;
-	}
-
 	private getTestSuite(type: string): TestSuite {
 		if (this.testSuites.has(type)) {
 			return this.testSuites.get(type) as TestSuite;
diff --git a/test/integration/goTest.explore.test.ts b/test/integration/goTest.explore.test.ts
index 0beda07..ebef7b0 100644
--- a/test/integration/goTest.explore.test.ts
+++ b/test/integration/goTest.explore.test.ts
@@ -60,11 +60,16 @@
 			async _didOpen(doc: TextDocument) {
 				await this.didOpenTextDocument(doc);
 			}
+
+			async _didCreate(doc: TextDocument) {
+				await this.didCreateFile(doc.uri);
+			}
 		}
 
 		interface TC extends TestCase {
-			open: string;
-			expect: string[];
+			uri: string;
+			expectCreate: string[];
+			expectOpen: string[];
 		}
 
 		const cases: Record<string, TC> = {
@@ -76,8 +81,9 @@
 					'/src/proj/bar_test.go': 'package main\nfunc TestBar(*testing.T) {}',
 					'/src/proj/baz/main_test.go': 'package main\nfunc TestBaz(*testing.T) {}'
 				},
-				open: 'file:///src/proj/foo_test.go',
-				expect: [
+				uri: 'file:///src/proj/foo_test.go',
+				expectCreate: ['file:///src/proj?module', 'file:///src/proj/foo_test.go?file'],
+				expectOpen: [
 					'file:///src/proj?module',
 					'file:///src/proj/foo_test.go?file',
 					'file:///src/proj/foo_test.go?test#TestFoo'
@@ -89,8 +95,9 @@
 					'/src/proj/go.mod': 'module test',
 					'/src/proj/foo_test.go': 'package main\nfunc TestFoo(*testing.T) {}'
 				},
-				open: 'file:///src/proj/foo_test.go',
-				expect: [
+				uri: 'file:///src/proj/foo_test.go',
+				expectCreate: ['file:///src/proj?module', 'file:///src/proj/foo_test.go?file'],
+				expectOpen: [
 					'file:///src/proj?module',
 					'file:///src/proj/foo_test.go?file',
 					'file:///src/proj/foo_test.go?test#TestFoo'
@@ -100,14 +107,17 @@
 
 		for (const name in cases) {
 			test(name, async () => {
-				const { workspace, files, open, expect } = cases[name];
+				const { workspace, files, uri: uri, expectCreate: expectCreate, expectOpen: expectOpen } = cases[name];
 				const { ctrl, expl, ws } = newExplorer(workspace, files, DUT);
 
-				const doc = ws.fs.files.get(open);
+				const doc = ws.fs.files.get(uri);
 				assert(doc);
-				await expl._didOpen(doc);
 
-				assertTestItems(ctrl.items, expect);
+				await expl._didCreate(doc);
+				assertTestItems(ctrl.items, expectCreate);
+
+				await expl._didOpen(doc);
+				assertTestItems(ctrl.items, expectOpen);
 			});
 		}
 	});