fix: preserve existing environment variables when creating terminals

- Modified Terminal.getEnv() to spread process.env first, preserving nix-shell and other environment variables
- Updated TerminalRegistry tests to use expect.objectContaining() for environment checks
- Added comprehensive tests for environment preservation in Terminal.env-preservation.spec.ts

Fixes #7021

src/integrations/terminal/Terminal.ts

@@ -151,7 +151,9 @@ export class Terminal extends BaseTerminal {
 	}
 
 	public static getEnv(): Record<string, string> {
+		// Start with the existing process environment to preserve nix-shell and other environment variables
 		const env: Record<string, string> = {
+			...process.env,
 			PAGER: process.platform === "win32" ? "" : "cat",
 
 			// VTE must be disabled because it prevents the prompt command from executing

src/integrations/terminal/__tests__/Terminal.env-preservation.spec.ts

@@ -0,0 +1,125 @@
+// npx vitest run src/integrations/terminal/__tests__/Terminal.env-preservation.spec.ts
+
+import { Terminal } from "../Terminal"
+
+describe("Terminal.getEnv() - Environment Preservation", () => {
+	let originalEnv: NodeJS.ProcessEnv
+
+	beforeEach(() => {
+		// Save original environment
+		originalEnv = { ...process.env }
+	})
+
+	afterEach(() => {
+		// Restore original environment
+		process.env = originalEnv
+	})
+
+	it("should preserve existing environment variables", () => {
+		// Set up test environment variables (simulating nix-shell)
+		process.env.NIX_BUILD_CORES = "4"
+		process.env.NIX_STORE = "/nix/store"
+		process.env.IN_NIX_SHELL = "impure"
+		process.env.CUSTOM_VAR = "custom_value"
+
+		const env = Terminal.getEnv()
+
+		// Check that nix-shell variables are preserved
+		expect(env.NIX_BUILD_CORES).toBe("4")
+		expect(env.NIX_STORE).toBe("/nix/store")
+		expect(env.IN_NIX_SHELL).toBe("impure")
+		expect(env.CUSTOM_VAR).toBe("custom_value")
+
+		// Check that Roo Code specific variables are still set
+		expect(env.PAGER).toBe(process.platform === "win32" ? "" : "cat")
+		expect(env.VTE_VERSION).toBe("0")
+	})
+
+	it("should override specific environment variables when needed", () => {
+		// Set conflicting environment variables
+		process.env.PAGER = "less"
+		process.env.VTE_VERSION = "6003"
+
+		const env = Terminal.getEnv()
+
+		// Check that Roo Code overrides take precedence
+		expect(env.PAGER).toBe(process.platform === "win32" ? "" : "cat")
+		expect(env.VTE_VERSION).toBe("0")
+	})
+
+	it("should preserve PATH and other critical environment variables", () => {
+		// Set critical environment variables
+		process.env.PATH = "/usr/local/bin:/usr/bin:/bin"
+		process.env.HOME = "/home/user"
+		process.env.USER = "testuser"
+		process.env.SHELL = "/bin/zsh"
+
+		const env = Terminal.getEnv()
+
+		// Check that critical variables are preserved
+		expect(env.PATH).toBe("/usr/local/bin:/usr/bin:/bin")
+		expect(env.HOME).toBe("/home/user")
+		expect(env.USER).toBe("testuser")
+		expect(env.SHELL).toBe("/bin/zsh")
+	})
+
+	it("should handle undefined environment variables gracefully", () => {
+		// Clear some environment variables
+		delete process.env.SOME_UNDEFINED_VAR
+
+		const env = Terminal.getEnv()
+
+		// Should not throw and should not include undefined values
+		expect(env.SOME_UNDEFINED_VAR).toBeUndefined()
+	})
+
+	it("should preserve nix-shell specific environment modifications", () => {
+		// Simulate a comprehensive nix-shell environment
+		process.env.NIX_BUILD_CORES = "8"
+		process.env.NIX_STORE = "/nix/store"
+		process.env.IN_NIX_SHELL = "impure"
+		process.env.NIX_ENFORCE_NO_NATIVE = "1"
+		process.env.PKG_CONFIG_PATH = "/nix/store/xxx/lib/pkgconfig"
+		process.env.NODE_PATH = "/nix/store/yyy/lib/node_modules"
+		process.env.buildInputs = "/nix/store/aaa /nix/store/bbb"
+		process.env.nativeBuildInputs = "/nix/store/ccc /nix/store/ddd"
+
+		const env = Terminal.getEnv()
+
+		// All nix-shell variables should be preserved
+		expect(env.NIX_BUILD_CORES).toBe("8")
+		expect(env.NIX_STORE).toBe("/nix/store")
+		expect(env.IN_NIX_SHELL).toBe("impure")
+		expect(env.NIX_ENFORCE_NO_NATIVE).toBe("1")
+		expect(env.PKG_CONFIG_PATH).toBe("/nix/store/xxx/lib/pkgconfig")
+		expect(env.NODE_PATH).toBe("/nix/store/yyy/lib/node_modules")
+		expect(env.buildInputs).toBe("/nix/store/aaa /nix/store/bbb")
+		expect(env.nativeBuildInputs).toBe("/nix/store/ccc /nix/store/ddd")
+	})
+
+	it("should add PROMPT_EOL_MARK when Terminal.getTerminalZshClearEolMark() is true", () => {
+		// This is the default behavior
+		const originalValue = Terminal.getTerminalZshClearEolMark()
+		Terminal.setTerminalZshClearEolMark(true)
+
+		try {
+			const env = Terminal.getEnv()
+			expect(env.PROMPT_EOL_MARK).toBe("")
+		} finally {
+			Terminal.setTerminalZshClearEolMark(originalValue)
+		}
+	})
+
+	it("should not override PROMPT_EOL_MARK when Terminal.getTerminalZshClearEolMark() is false", () => {
+		const originalValue = Terminal.getTerminalZshClearEolMark()
+		Terminal.setTerminalZshClearEolMark(false)
+		process.env.PROMPT_EOL_MARK = "%"
+
+		try {
+			const env = Terminal.getEnv()
+			expect(env.PROMPT_EOL_MARK).toBe("%")
+		} finally {
+			Terminal.setTerminalZshClearEolMark(originalValue)
+		}
+	})
+})

src/integrations/terminal/__tests__/TerminalRegistry.spec.ts

@@ -44,11 +44,11 @@ describe("TerminalRegistry", () => {
 				cwd: "/test/path",
 				name: "Roo Code",
 				iconPath: expect.any(Object),
-				env: {
+				env: expect.objectContaining({
 					PAGER,
 					VTE_VERSION: "0",
 					PROMPT_EOL_MARK: "",
-				},
+				}),
 			})
 		})
 
@@ -64,12 +64,12 @@ describe("TerminalRegistry", () => {
 					cwd: "/test/path",
 					name: "Roo Code",
 					iconPath: expect.any(Object),
-					env: {
+					env: expect.objectContaining({
 						PAGER,
 						PROMPT_COMMAND: "sleep 0.05",
 						VTE_VERSION: "0",
 						PROMPT_EOL_MARK: "",
-					},
+					}),
 				})
 			} finally {
 				// Restore original delay
@@ -86,12 +86,12 @@ describe("TerminalRegistry", () => {
 					cwd: "/test/path",
 					name: "Roo Code",
 					iconPath: expect.any(Object),
-					env: {
+					env: expect.objectContaining({
 						PAGER,
 						VTE_VERSION: "0",
 						PROMPT_EOL_MARK: "",
 						ITERM_SHELL_INTEGRATION_INSTALLED: "Yes",
-					},
+					}),
 				})
 			} finally {
 				Terminal.setTerminalZshOhMy(false)
@@ -107,12 +107,12 @@ describe("TerminalRegistry", () => {
 					cwd: "/test/path",
 					name: "Roo Code",
 					iconPath: expect.any(Object),
-					env: {
+					env: expect.objectContaining({
 						PAGER,
 						VTE_VERSION: "0",
 						PROMPT_EOL_MARK: "",
 						POWERLEVEL9K_TERM_SHELL_INTEGRATION: "true",
-					},
+					}),
 				})
 			} finally {
 				Terminal.setTerminalZshP10k(false)