Revert "Smart truncation for terminal output"

This reverts commit 7eee3e0.

Middle-out truncation is a really great feature and it should still be
implemented, however it unnecessarily interferes with #1365 because it
hooked into the low-level chunk management that comes directly from VSCE
shell integration.

The best place to hook OutputBuilder is as follows depending on the
state of terminal interaction:

1. Foreground terminals:

Cline.ts:
	 executeCommandTool(...) {
	     process.on("line", (line) => {
		    lines.push(line)
		    ...
	    }
	 }

2. For background terminals: hook in at the point that getUnretrievedOutput is consumed for active or
   inactive terminals in Cline.ts:getEnvironmentDetails()

Please note:

The Terminal classes are very sensitive to change, partially because of
the complicated way that shell integration works with VSCE, and
partially because of the way that Cline interacts with the Terminal*
class abstractions that make VSCE shell integration easier to work with.

At the point that PR#1365 is merged, it is unlikely that any Terminal*
classes will need to be modified substantially.  Generally speaking, we
should think of this is a stable interface and minimize changes.

Reverts: #1390

Author: Eric Wheeler

src/core/Cline.ts

@@ -25,6 +25,7 @@ import {
 	addLineNumbers,
 	stripLineNumbers,
 	everyLineHasLineNumbers,
+	truncateOutput,
 } from "../integrations/misc/extract-text"
 import { TerminalManager, ExitCodeDetails } from "../integrations/terminal/TerminalManager"
 import { UrlContentFetcher } from "../services/browser/UrlContentFetcher"
@@ -59,7 +60,7 @@ import { calculateApiCostAnthropic } from "../utils/cost"
 import { fileExistsAtPath } from "../utils/fs"
 import { arePathsEqual, getReadablePath } from "../utils/path"
 import { parseMentions } from "./mentions"
-import { RooIgnoreController } from "./ignore/RooIgnoreController"
+import { RooIgnoreController, LOCK_TEXT_SYMBOL } from "./ignore/RooIgnoreController"
 import { AssistantMessageContent, parseAssistantMessage, ToolParamName, ToolUseName } from "./assistant-message"
 import { formatResponse } from "./prompts/responses"
 import { SYSTEM_PROMPT } from "./prompts/system"
@@ -70,7 +71,6 @@ import { BrowserSession } from "../services/browser/BrowserSession"
 import { McpHub } from "../services/mcp/McpHub"
 import crypto from "crypto"
 import { insertGroups } from "./diff/insert-groups"
-import { OutputBuilder } from "../integrations/terminal/OutputBuilder"
 import { telemetryService } from "../services/telemetry/TelemetryService"
 
 const cwd =
@@ -919,52 +919,44 @@ export class Cline {
 	// Tools
 
 	async executeCommandTool(command: string): Promise<[boolean, ToolResponse]> {
-		const { terminalOutputLimit } = (await this.providerRef.deref()?.getState()) ?? {}
-
 		const terminalInfo = await this.terminalManager.getOrCreateTerminal(cwd)
-		// Weird visual bug when creating new terminals (even manually) where
-		// there's an empty space at the top.
-		terminalInfo.terminal.show()
-		const process = this.terminalManager.runCommand(terminalInfo, command, terminalOutputLimit)
+		terminalInfo.terminal.show() // weird visual bug when creating new terminals (even manually) where there's an empty space at the top.
+		const process = this.terminalManager.runCommand(terminalInfo, command)
 
 		let userFeedback: { text?: string; images?: string[] } | undefined
 		let didContinue = false
-
-		const sendCommandOutput = async (line: string) => {
+		const sendCommandOutput = async (line: string): Promise<void> => {
 			try {
 				const { response, text, images } = await this.ask("command_output", line)
-
 				if (response === "yesButtonClicked") {
-					// Proceed while running.
+					// proceed while running
 				} else {
 					userFeedback = { text, images }
 				}
-
 				didContinue = true
-				process.continue() // Continue past the await.
+				process.continue() // continue past the await
 			} catch {
-				// This can only happen if this ask promise was ignored, so ignore this error.
+				// This can only happen if this ask promise was ignored, so ignore this error
 			}
 		}
 
-		let completed = false
-		let exitDetails: ExitCodeDetails | undefined
-
-		let builder = new OutputBuilder({ maxSize: terminalOutputLimit })
-		let output: string | undefined = undefined
-
+		let lines: string[] = []
 		process.on("line", (line) => {
-			builder.append(line)
-
+			lines.push(line)
 			if (!didContinue) {
 				sendCommandOutput(line)
 			} else {
 				this.say("command_output", line)
 			}
 		})
 
-		process.once("completed", (buffer?: string) => {
-			output = buffer
+		let completed = false
+		let exitDetails: ExitCodeDetails | undefined
+		process.once("completed", (output?: string) => {
+			// Use provided output if available, otherwise keep existing result.
+			if (output) {
+				lines = output.split("\n")
+			}
 			completed = true
 		})
 
@@ -980,17 +972,19 @@ export class Cline {
 
 		await process
 
-		// Wait for a short delay to ensure all messages are sent to the webview.
+		// Wait for a short delay to ensure all messages are sent to the webview
 		// This delay allows time for non-awaited promises to be created and
 		// for their associated messages to be sent to the webview, maintaining
 		// the correct order of messages (although the webview is smart about
-		// grouping command_output messages despite any gaps anyways).
+		// grouping command_output messages despite any gaps anyways)
 		await delay(50)
-		const result = output || builder.content
+
+		const { terminalOutputLineLimit } = (await this.providerRef.deref()?.getState()) ?? {}
+		const output = truncateOutput(lines.join("\n"), terminalOutputLineLimit)
+		const result = output.trim()
 
 		if (userFeedback) {
 			await this.say("user_feedback", userFeedback.text, userFeedback.images)
-
 			return [
 				true,
 				formatResponse.toolResult(
@@ -1004,28 +998,25 @@ export class Cline {
 
 		if (completed) {
 			let exitStatus = "No exit code available"
-
 			if (exitDetails !== undefined) {
 				if (exitDetails.signal) {
 					exitStatus = `Process terminated by signal ${exitDetails.signal} (${exitDetails.signalName})`
-
 					if (exitDetails.coreDumpPossible) {
 						exitStatus += " - core dump possible"
 					}
 				} else {
 					exitStatus = `Exit code: ${exitDetails.exitCode}`
 				}
 			}
-
 			return [false, `Command executed. ${exitStatus}${result.length > 0 ? `\nOutput:\n${result}` : ""}`]
+		} else {
+			return [
+				false,
+				`Command is still running in the user's terminal.${
+					result.length > 0 ? `\nHere's the output so far:\n${result}` : ""
+				}\n\nYou will be updated on the terminal status and new output in the future.`,
+			]
 		}
-
-		return [
-			false,
-			`Command is still running in the user's terminal.${
-				result.length > 0 ? `\nHere's the output so far:\n${result}` : ""
-			}\n\nYou will be updated on the terminal status and new output in the future.`,
-		]
 	}
 
 	async *attemptApiRequest(previousApiReqIndex: number, retryAttempt: number = 0): ApiStream {
@@ -3525,7 +3516,7 @@ export class Cline {
 			terminalDetails += "\n\n# Actively Running Terminals"
 			for (const busyTerminal of busyTerminals) {
 				terminalDetails += `\n## Original command: \`${busyTerminal.lastCommand}\``
-				const newOutput = this.terminalManager.readLine(busyTerminal.id)
+				const newOutput = this.terminalManager.getUnretrievedOutput(busyTerminal.id)
 				if (newOutput) {
 					terminalDetails += `\n### New Output\n${newOutput}`
 				} else {
@@ -3537,7 +3528,7 @@ export class Cline {
 		if (inactiveTerminals.length > 0) {
 			const inactiveTerminalOutputs = new Map<number, string>()
 			for (const inactiveTerminal of inactiveTerminals) {
-				const newOutput = this.terminalManager.readLine(inactiveTerminal.id)
+				const newOutput = this.terminalManager.getUnretrievedOutput(inactiveTerminal.id)
 				if (newOutput) {
 					inactiveTerminalOutputs.set(inactiveTerminal.id, newOutput)
 				}

src/core/mentions/index.ts

@@ -2,13 +2,13 @@ import * as vscode from "vscode"
 import * as path from "path"
 import { openFile } from "../../integrations/misc/open-file"
 import { UrlContentFetcher } from "../../services/browser/UrlContentFetcher"
-import { mentionRegexGlobal } from "../../shared/context-mentions"
+import { mentionRegexGlobal, formatGitSuggestion, type MentionSuggestion } from "../../shared/context-mentions"
 import fs from "fs/promises"
 import { extractTextFromFile } from "../../integrations/misc/extract-text"
 import { isBinaryFile } from "isbinaryfile"
 import { diagnosticsToProblemsString } from "../../integrations/diagnostics"
 import { getCommitInfo, getWorkingState } from "../../utils/git"
-import { getLatestTerminalOutput } from "../../integrations/terminal/getLatestTerminalOutput"
+import { getLatestTerminalOutput } from "../../integrations/terminal/get-latest-output"
 
 export async function openMention(mention?: string): Promise<void> {
 	if (!mention) {

src/core/webview/ClineProvider.ts

@@ -10,18 +10,17 @@ import simpleGit from "simple-git"
 
 import { setPanel } from "../../activate/registerCommands"
 import { ApiConfiguration, ApiProvider, ModelInfo, API_CONFIG_KEYS } from "../../shared/api"
+import { CheckpointStorage } from "../../shared/checkpoints"
 import { findLast } from "../../shared/array"
-import { supportPrompt } from "../../shared/support-prompt"
+import { CustomSupportPrompts, supportPrompt } from "../../shared/support-prompt"
 import { GlobalFileNames } from "../../shared/globalFileNames"
 import { SecretKey, GlobalStateKey, SECRET_KEYS, GLOBAL_STATE_KEYS } from "../../shared/globalState"
 import { HistoryItem } from "../../shared/HistoryItem"
-import { CheckpointStorage } from "../../shared/checkpoints"
 import { ApiConfigMeta, ExtensionMessage } from "../../shared/ExtensionMessage"
 import { checkoutDiffPayloadSchema, checkoutRestorePayloadSchema, WebviewMessage } from "../../shared/WebviewMessage"
-import { Mode, PromptComponent, defaultModeSlug, ModeConfig } from "../../shared/modes"
+import { Mode, CustomModePrompts, PromptComponent, defaultModeSlug, ModeConfig } from "../../shared/modes"
 import { checkExistKey } from "../../shared/checkExistApiConfig"
 import { EXPERIMENT_IDS, experiments as Experiments, experimentDefault, ExperimentId } from "../../shared/experiments"
-import { TERMINAL_OUTPUT_LIMIT } from "../../shared/terminal"
 import { downloadTask } from "../../integrations/misc/export-markdown"
 import { openFile, openImage } from "../../integrations/misc/open-file"
 import { selectImages } from "../../integrations/misc/process-images"
@@ -1255,6 +1254,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 						await this.postStateToWebview()
 						break
 					case "checkpointStorage":
+						console.log(`[ClineProvider] checkpointStorage: ${message.text}`)
 						const checkpointStorage = message.text ?? "task"
 						await this.updateGlobalState("checkpointStorage", checkpointStorage)
 						await this.postStateToWebview()
@@ -1387,8 +1387,8 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 						await this.updateGlobalState("writeDelayMs", message.value)
 						await this.postStateToWebview()
 						break
-					case "terminalOutputLimit":
-						await this.updateGlobalState("terminalOutputLimit", message.value)
+					case "terminalOutputLineLimit":
+						await this.updateGlobalState("terminalOutputLineLimit", message.value)
 						await this.postStateToWebview()
 						break
 					case "mode":
@@ -2315,7 +2315,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			remoteBrowserEnabled,
 			preferredLanguage,
 			writeDelayMs,
-			terminalOutputLimit,
+			terminalOutputLineLimit,
 			fuzzyMatchThreshold,
 			mcpEnabled,
 			enableMcpServerCreation,
@@ -2375,7 +2375,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			remoteBrowserEnabled: remoteBrowserEnabled ?? false,
 			preferredLanguage: preferredLanguage ?? "English",
 			writeDelayMs: writeDelayMs ?? 1000,
-			terminalOutputLimit: terminalOutputLimit ?? TERMINAL_OUTPUT_LIMIT,
+			terminalOutputLineLimit: terminalOutputLineLimit ?? 500,
 			fuzzyMatchThreshold: fuzzyMatchThreshold ?? 1.0,
 			mcpEnabled: mcpEnabled ?? true,
 			enableMcpServerCreation: enableMcpServerCreation ?? true,
@@ -2530,7 +2530,7 @@ export class ClineProvider implements vscode.WebviewViewProvider {
 			remoteBrowserEnabled: stateValues.remoteBrowserEnabled ?? false,
 			fuzzyMatchThreshold: stateValues.fuzzyMatchThreshold ?? 1.0,
 			writeDelayMs: stateValues.writeDelayMs ?? 1000,
-			terminalOutputLimit: stateValues.terminalOutputLimit ?? TERMINAL_OUTPUT_LIMIT,
+			terminalOutputLineLimit: stateValues.terminalOutputLineLimit ?? 500,
 			mode: stateValues.mode ?? defaultModeSlug,
 			preferredLanguage:
 				stateValues.preferredLanguage ??

src/integrations/misc/__tests__/extract-text.test.ts

@@ -1,4 +1,4 @@
-import { addLineNumbers, everyLineHasLineNumbers, stripLineNumbers } from "../extract-text"
+import { addLineNumbers, everyLineHasLineNumbers, stripLineNumbers, truncateOutput } from "../extract-text"
 
 describe("addLineNumbers", () => {
 	it("should add line numbers starting from 1 by default", () => {
@@ -101,3 +101,67 @@ describe("stripLineNumbers", () => {
 		expect(stripLineNumbers(input)).toBe(expected)
 	})
 })
+
+describe("truncateOutput", () => {
+	it("returns original content when no line limit provided", () => {
+		const content = "line1\nline2\nline3"
+		expect(truncateOutput(content)).toBe(content)
+	})
+
+	it("returns original content when lines are under limit", () => {
+		const content = "line1\nline2\nline3"
+		expect(truncateOutput(content, 5)).toBe(content)
+	})
+
+	it("truncates content with 20/80 split when over limit", () => {
+		// Create 25 lines of content
+		const lines = Array.from({ length: 25 }, (_, i) => `line${i + 1}`)
+		const content = lines.join("\n")
+
+		// Set limit to 10 lines
+		const result = truncateOutput(content, 10)
+
+		// Should keep:
+		// - First 2 lines (20% of 10)
+		// - Last 8 lines (80% of 10)
+		// - Omission indicator in between
+		const expectedLines = [
+			"line1",
+			"line2",
+			"",
+			"[...15 lines omitted...]",
+			"",
+			"line18",
+			"line19",
+			"line20",
+			"line21",
+			"line22",
+			"line23",
+			"line24",
+			"line25",
+		]
+		expect(result).toBe(expectedLines.join("\n"))
+	})
+
+	it("handles empty content", () => {
+		expect(truncateOutput("", 10)).toBe("")
+	})
+
+	it("handles single line content", () => {
+		expect(truncateOutput("single line", 10)).toBe("single line")
+	})
+
+	it("handles windows-style line endings", () => {
+		// Create content with windows line endings
+		const lines = Array.from({ length: 15 }, (_, i) => `line${i + 1}`)
+		const content = lines.join("\r\n")
+
+		const result = truncateOutput(content, 5)
+
+		// Should keep first line (20% of 5 = 1) and last 4 lines (80% of 5 = 4)
+		// Split result by either \r\n or \n to normalize line endings
+		const resultLines = result.split(/\r?\n/)
+		const expectedLines = ["line1", "", "[...10 lines omitted...]", "", "line12", "line13", "line14", "line15"]
+		expect(resultLines).toEqual(expectedLines)
+	})
+})

src/integrations/misc/extract-text.ts

@@ -89,3 +89,37 @@ export function stripLineNumbers(content: string): string {
 	const lineEnding = content.includes("\r\n") ? "\r\n" : "\n"
 	return processedLines.join(lineEnding)
 }
+
+/**
+ * Truncates multi-line output while preserving context from both the beginning and end.
+ * When truncation is needed, it keeps 20% of the lines from the start and 80% from the end,
+ * with a clear indicator of how many lines were omitted in between.
+ *
+ * @param content The multi-line string to truncate
+ * @param lineLimit Optional maximum number of lines to keep. If not provided or 0, returns the original content
+ * @returns The truncated string with an indicator of omitted lines, or the original content if no truncation needed
+ *
+ * @example
+ * // With 10 line limit on 25 lines of content:
+ * // - Keeps first 2 lines (20% of 10)
+ * // - Keeps last 8 lines (80% of 10)
+ * // - Adds "[...15 lines omitted...]" in between
+ */
+export function truncateOutput(content: string, lineLimit?: number): string {
+	if (!lineLimit) {
+		return content
+	}
+
+	const lines = content.split("\n")
+	if (lines.length <= lineLimit) {
+		return content
+	}
+
+	const beforeLimit = Math.floor(lineLimit * 0.2) // 20% of lines before
+	const afterLimit = lineLimit - beforeLimit // remaining 80% after
+	return [
+		...lines.slice(0, beforeLimit),
+		`\n[...${lines.length - lineLimit} lines omitted...]\n`,
+		...lines.slice(-afterLimit),
+	].join("\n")
+}