Fix language passing

Author: mrubens

src/core/Cline.ts

@@ -3692,12 +3692,13 @@ export class Cline extends EventEmitter<ClineEvents> {
 			customModePrompts,
 			experiments = {} as Record<ExperimentId, boolean>,
 			customInstructions: globalCustomInstructions,
+			language,
 		} = (await this.providerRef.deref()?.getState()) ?? {}
 		const currentMode = mode ?? defaultModeSlug
 		const modeDetails = await getFullModeDetails(currentMode, customModes, customModePrompts, {
 			cwd,
 			globalCustomInstructions,
-			language: formatLanguage(vscode.env.language),
+			language: language ?? formatLanguage(vscode.env.language),
 		})
 		details += `\n\n# Current Mode\n`
 		details += `<slug>${currentMode}</slug>\n`

src/core/prompts/system.ts

@@ -41,6 +41,7 @@ async function generatePrompt(
 	diffEnabled?: boolean,
 	experiments?: Record<string, boolean>,
 	enableMcpServerCreation?: boolean,
+	language?: string,
 	rooIgnoreInstructions?: string,
 ): Promise<string> {
 	if (!context) {
@@ -109,6 +110,7 @@ export const SYSTEM_PROMPT = async (
 	diffEnabled?: boolean,
 	experiments?: Record<string, boolean>,
 	enableMcpServerCreation?: boolean,
+	language?: string,
 	rooIgnoreInstructions?: string,
 ): Promise<string> => {
 	if (!context) {
@@ -139,7 +141,7 @@ export const SYSTEM_PROMPT = async (
 			globalCustomInstructions || "",
 			cwd,
 			mode,
-			{ language: formatLanguage(vscode.env.language), rooIgnoreInstructions },
+			{ language: language ?? formatLanguage(vscode.env.language), rooIgnoreInstructions },
 		)
 		// For file-based prompts, don't include the tool sections
 		return `${roleDefinition}
@@ -166,6 +168,7 @@ ${customInstructions}`
 		diffEnabled,
 		experiments,
 		enableMcpServerCreation,
+		language,
 		rooIgnoreInstructions,
 	)
 }

src/core/webview/ClineProvider.ts

@@ -2545,7 +2545,7 @@ export class ClineProvider extends EventEmitter<ClineProviderEvents> implements
 			writeDelayMs: stateValues.writeDelayMs ?? 1000,
 			terminalOutputLineLimit: stateValues.terminalOutputLineLimit ?? 500,
 			mode: stateValues.mode ?? defaultModeSlug,
-			language: stateValues.language || formatLanguage(vscode.env.language),
+			language: stateValues.language ?? formatLanguage(vscode.env.language),
 			mcpEnabled: stateValues.mcpEnabled ?? true,
 			enableMcpServerCreation: stateValues.enableMcpServerCreation ?? true,
 			alwaysApproveResubmit: stateValues.alwaysApproveResubmit ?? false,