refactor(fs): consolidate safeReadFile implementation

- Moved `safeReadFile` function from multiple files to `src/utils/fs.ts`
- Updated imports in affected files to use the centralized `safeReadFile` function
- Simplified file reading logic by removing redundant implementations

Author: devxpain

src/core/prompts/sections/custom-instructions.ts

@@ -5,22 +5,7 @@ import { Dirent } from "fs"
 import { isLanguage } from "@roo-code/types"
 
 import { LANGUAGES } from "../../../shared/language"
-
-/**
- * Safely read a file and return its trimmed content
- */
-async function safeReadFile(filePath: string): Promise<string> {
-	try {
-		const content = await fs.readFile(filePath, "utf-8")
-		return content.trim()
-	} catch (err) {
-		const errorCode = (err as NodeJS.ErrnoException).code
-		if (!errorCode || !["ENOENT", "EISDIR"].includes(errorCode)) {
-			throw err
-		}
-		return ""
-	}
-}
+import { safeReadFile } from "../../../utils/fs"
 
 /**
  * Check if a directory exists

src/core/prompts/sections/custom-system-prompt.ts

@@ -1,7 +1,7 @@
 import fs from "fs/promises"
 import path from "path"
 import { Mode } from "../../../shared/modes"
-import { fileExistsAtPath } from "../../../utils/fs"
+import { fileExistsAtPath, safeReadFile } from "../../../utils/fs"
 
 export type PromptVariables = {
 	workspace?: string
@@ -25,23 +25,6 @@ function interpolatePromptContent(content: string, variables: PromptVariables):
 	return interpolatedContent
 }
 
-/**
- * Safely reads a file, returning an empty string if the file doesn't exist
- */
-async function safeReadFile(filePath: string): Promise<string> {
-	try {
-		const content = await fs.readFile(filePath, "utf-8")
-		// When reading with "utf-8" encoding, content should be a string
-		return content.trim()
-	} catch (err) {
-		const errorCode = (err as NodeJS.ErrnoException).code
-		if (!errorCode || !["ENOENT", "EISDIR"].includes(errorCode)) {
-			throw err
-		}
-		return ""
-	}
-}
-
 /**
  * Get the path to a system prompt file for a specific mode
  */

src/core/webview/ClineProvider.ts

@@ -50,7 +50,7 @@ import { McpServerManager } from "../../services/mcp/McpServerManager"
 import { ShadowCheckpointService } from "../../services/checkpoints/ShadowCheckpointService"
 import { CodeIndexManager } from "../../services/code-index/manager"
 import type { IndexProgressUpdate } from "../../services/code-index/interfaces/manager"
-import { fileExistsAtPath } from "../../utils/fs"
+import { fileExistsAtPath, safeReadFile } from "../../utils/fs"
 import { setTtsEnabled, setTtsSpeed } from "../../utils/tts"
 import { ContextProxy } from "../config/ContextProxy"
 import { ProviderSettingsManager } from "../config/ProviderSettingsManager"
@@ -988,6 +988,16 @@ export class ClineProvider
 		await this.initClineWithHistoryItem({ ...historyItem, rootTask, parentTask })
 	}
 
+	// Settings Directory
+
+	async ensureSettingsDirectoryExists(): Promise<string> {
+		const { getSettingsDirectoryPath } = await import("../../utils/storage")
+		const globalStoragePath = this.contextProxy.globalStorageUri.fsPath
+		return getSettingsDirectoryPath(globalStoragePath)
+	}
+
+	// Custom Instructions
+
 	async updateCustomInstructions(instructions?: string) {
 		const settingsDirPath = await this.ensureSettingsDirectoryExists()
 		const customInstructionsFilePath = path.join(settingsDirPath, GlobalFileNames.customInstructions)
@@ -1017,17 +1027,14 @@ export class ClineProvider
 	}
 
 	async refreshCustomInstructions(): Promise<void> {
+		const content = await this.readCustomInstructionsFromFile()
+		await this.updateCustomInstructions(content)
+	}
+
+	private async readCustomInstructionsFromFile(): Promise<string | undefined> {
 		const settingsDirPath = await this.ensureSettingsDirectoryExists()
 		const customInstructionsFilePath = path.join(settingsDirPath, GlobalFileNames.customInstructions)
-		let content: string | undefined = undefined
-		try {
-			content = await fs.readFile(customInstructionsFilePath, "utf-8")
-		} catch (error) {
-			if ((error as NodeJS.ErrnoException).code !== "ENOENT") {
-				throw error
-			}
-		}
-		await this.updateCustomInstructions(content)
+		return await safeReadFile(customInstructionsFilePath)
 	}
 
 	// MCP
@@ -1055,27 +1062,6 @@ export class ClineProvider
 		return mcpServersDir
 	}
 
-	async ensureSettingsDirectoryExists(): Promise<string> {
-		const { getSettingsDirectoryPath } = await import("../../utils/storage")
-		const globalStoragePath = this.contextProxy.globalStorageUri.fsPath
-		return getSettingsDirectoryPath(globalStoragePath)
-	}
-
-	private async readCustomInstructionsFromFile(): Promise<string | undefined> {
-		const settingsDirPath = await this.ensureSettingsDirectoryExists()
-		const customInstructionsFilePath = path.join(settingsDirPath, GlobalFileNames.customInstructions)
-
-		if (await fileExistsAtPath(customInstructionsFilePath)) {
-			try {
-				return await fs.readFile(customInstructionsFilePath, "utf-8")
-			} catch (error) {
-				this.log(`Error reading custom instructions file: ${error}`)
-				return undefined
-			}
-		}
-		return undefined
-	}
-
 	// OpenRouter
 
 	async handleOpenRouterCallback(code: string) {

src/utils/fs.ts

@@ -45,3 +45,19 @@ export async function fileExistsAtPath(filePath: string): Promise<boolean> {
 		return false
 	}
 }
+
+/**
+ * Safely read a file and return its trimmed content
+ */
+export async function safeReadFile(filePath: string): Promise<string> {
+	try {
+		const content = await fs.readFile(filePath, "utf-8")
+		return content.trim()
+	} catch (err) {
+		const errorCode = (err as NodeJS.ErrnoException).code
+		if (!errorCode || !["ENOENT", "EISDIR"].includes(errorCode)) {
+			throw err
+		}
+		return ""
+	}
+}