From c6e97630681426fe89b2cd386ad74576eccf81ed Mon Sep 17 00:00:00 2001
From: roboomp <omp@can.ac>
Date: Thu, 16 Jul 2026 19:55:50 +0000
Subject: [PATCH] fix(lsp): returned null for missing configuration

Answered unconfigured workspace/configuration sections with the spec-required null value and covered the Roslyn post-initialization pull path.

Fixes #5745
---
 packages/coding-agent/CHANGELOG.md            |  4 +
 packages/coding-agent/src/lsp/client.ts       |  2 +-
 .../test/tools/lsp-regressions.test.ts        | 97 +++++++++++++++++++
 3 files changed, 102 insertions(+), 1 deletion(-)

diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index 0e753ced7..f86c8d28a 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed custom LSP servers such as `roslyn-language-server` crashing after initialization when they request unconfigured `workspace/configuration` sections; missing settings now receive the spec-required `null` instead of `{}` ([#5745](https://github.com/can1357/oh-my-pi/issues/5745)).
+
 ## [17.0.1] - 2026-07-16
 
 ### Changed
diff --git a/packages/coding-agent/src/lsp/client.ts b/packages/coding-agent/src/lsp/client.ts
index e511f7cc8..37a3e2ab8 100644
--- a/packages/coding-agent/src/lsp/client.ts
+++ b/packages/coding-agent/src/lsp/client.ts
@@ -428,7 +428,7 @@ async function handleConfigurationRequest(client: LspClient, message: LspJsonRpc
 	const items = params?.items ?? [];
 	const result = items.map(item => {
 		const section = item.section ?? "";
-		return client.config.settings?.[section] ?? {};
+		return client.config.settings?.[section] ?? null;
 	});
 	await sendResponse(client, message.id, result, "workspace/configuration");
 }
diff --git a/packages/coding-agent/test/tools/lsp-regressions.test.ts b/packages/coding-agent/test/tools/lsp-regressions.test.ts
index 2e52b5973..467fee72f 100644
--- a/packages/coding-agent/test/tools/lsp-regressions.test.ts
+++ b/packages/coding-agent/test/tools/lsp-regressions.test.ts
@@ -429,6 +429,103 @@ describe("lsp regressions", () => {
 		}
 	});
 
+	it("answers missing workspace configuration sections with null in request order", async () => {
+		const tempDir = TempDir.createSync("@omp-lsp-configuration-null-");
+		try {
+			const server = installFakeLsp((message, srv) => {
+				if (message.method === "initialize") {
+					srv.send({ jsonrpc: "2.0", id: message.id, result: { capabilities: {} } });
+				} else if (message.method === "initialized") {
+					srv.send({
+						jsonrpc: "2.0",
+						id: 5745,
+						method: "workspace/configuration",
+						params: {
+							items: [
+								{ section: "razor.format.attribute_indent_style" },
+								{ section: "html.auto_closing_tags" },
+								{},
+							],
+						},
+					});
+				} else if (message.method === "shutdown") {
+					srv.send({ jsonrpc: "2.0", id: message.id, result: null });
+				} else if (message.method === "exit") {
+					srv.exit(0);
+				}
+			});
+			const config: ServerConfig = {
+				command: "fake-lsp",
+				fileTypes: ["cs"],
+				rootMarkers: [],
+				settings: { "html.auto_closing_tags": true },
+			};
+
+			await lspClient.getOrCreateClient(config, tempDir.path(), 1_000);
+			const response = await server.waitFor(message => message.id === 5745 && message.method === undefined);
+
+			expect(response.result).toEqual([null, true, null]);
+		} finally {
+			await lspClient.shutdownAll();
+			tempDir.removeSync();
+		}
+	});
+
+	it("keeps the session alive when configuration is pulled after didChangeConfiguration", async () => {
+		const tempDir = TempDir.createSync("@omp-lsp-configuration-session-");
+		let configurationAccepted = false;
+		try {
+			const server = installFakeLsp((message, srv) => {
+				if (message.method === "initialize") {
+					srv.send({ jsonrpc: "2.0", id: message.id, result: { capabilities: { hoverProvider: true } } });
+				} else if (message.method === "workspace/didChangeConfiguration") {
+					srv.send({
+						jsonrpc: "2.0",
+						id: "roslyn-config",
+						method: "workspace/configuration",
+						params: { items: [{ section: "razor.format.attribute_indent_style" }] },
+					});
+				} else if (message.id === "roslyn-config" && message.method === undefined) {
+					if (Array.isArray(message.result) && message.result[0] === null) {
+						configurationAccepted = true;
+					} else {
+						srv.exit(-6);
+					}
+				} else if (message.method === "textDocument/hover" && configurationAccepted) {
+					srv.send({ jsonrpc: "2.0", id: message.id, result: { contents: "string C.Target" } });
+				} else if (message.method === "shutdown") {
+					srv.send({ jsonrpc: "2.0", id: message.id, result: null });
+				} else if (message.method === "exit") {
+					srv.exit(0);
+				}
+			});
+			const config: ServerConfig = {
+				command: "fake-lsp",
+				fileTypes: ["cs"],
+				rootMarkers: [],
+			};
+
+			const client = await lspClient.getOrCreateClient(config, tempDir.path(), 1_000);
+			await server.waitFor(message => message.id === "roslyn-config" && message.method === undefined);
+			const result = await lspClient.sendRequest(
+				client,
+				"textDocument/hover",
+				{
+					textDocument: { uri: fileToUri(path.join(tempDir.path(), "Target.cs")) },
+					position: { line: 0, character: 6 },
+				},
+				undefined,
+				50,
+			);
+
+			expect(result).toEqual({ contents: "string C.Target" });
+			expect(configurationAccepted).toBe(true);
+		} finally {
+			await lspClient.shutdownAll();
+			tempDir.removeSync();
+		}
+	});
+
 	it("accepts dynamic capability registration before semantic requests", async () => {
 		const tempDir = TempDir.createSync("@omp-lsp-dynamic-registration-");
 		try {