Add granular tool permissions settings (#46112)

Adds granular per-tool permission settings for the Zed agent with
regex-based rules.

Release Notes:

- N/A

---------

Co-authored-by: Amp <amp@ampcode.com>
This commit is contained in:
Richard Feldman 2026-01-08 17:32:18 -05:00 committed by GitHub
parent 0f75c079a5
commit 7a0b19b6b5
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
9 changed files with 699 additions and 861 deletions

2
Cargo.lock generated
View file

@ -312,8 +312,10 @@ dependencies = [
"fs",
"gpui",
"language_model",
"log",
"paths",
"project",
"regex",
"schemars",
"serde",
"serde_json",

View file

@ -961,6 +961,102 @@
// Note: This setting has no effect on external agents that support permission modes, such as Claude Code.
// You can set `agent_servers.claude.default_mode` to `bypassPermissions` to skip all permission requests.
"always_allow_tool_actions": false,
// Per-tool permission rules for granular control over tool actions.
// This setting only applies to the native Zed agent.
"tool_permissions": {
"tools": {
"terminal": {
"default_mode": "confirm",
"always_deny": [
// Dangerous rm commands
{ "pattern": "rm\\s+-rf\\s+(/|\\.\\.|\"|~|\\*)" },
{ "pattern": "rm\\s+-rf\\s*$" },
// Disk destruction
{ "pattern": "> /dev/sd" },
{ "pattern": "mkfs\\." },
{ "pattern": "dd\\s+if=/dev/(zero|random)" },
// Fork bomb
{ "pattern": ":\\(\\)\\{\\s*:\\|:&\\s*\\};:" },
// System files
{ "pattern": "/etc/passwd" },
{ "pattern": "/etc/shadow" },
// Windows destructive commands
{ "pattern": "del /f /s /q c:\\\\" },
{ "pattern": "format c:" },
{ "pattern": "rd /s /q" },
],
"always_confirm": [
// File deletion
{ "pattern": "rm\\s" },
// Destructive git operations
{ "pattern": "git\\s+(reset|clean)\\s+--hard" },
{ "pattern": "git\\s+push\\s+(-f|--force)" },
// Database operations
{ "pattern": "DROP\\s+TABLE", "case_sensitive": true },
{ "pattern": "DELETE\\s+FROM", "case_sensitive": true },
// Privileged commands
{ "pattern": "sudo\\s" },
],
"always_allow": [
// Build and test commands
{ "pattern": "^cargo\\s+(build|test|check|clippy|run)" },
{ "pattern": "^npm\\s+(test|run|install)" },
{ "pattern": "^pnpm\\s+(test|run|install)" },
{ "pattern": "^yarn\\s+(test|run|install)" },
// Safe read-only commands
{ "pattern": "^ls(\\s|$)" },
{ "pattern": "^cat\\s" },
{ "pattern": "^head\\s" },
{ "pattern": "^tail\\s" },
{ "pattern": "^grep\\s" },
{ "pattern": "^find\\s" },
// Safe git commands
{ "pattern": "^git\\s+(status|log|diff|branch|show)" },
],
},
"edit_file": {
"default_mode": "confirm",
"always_deny": [
// Secrets and credentials
{ "pattern": "\\.env($|\\.)" },
{ "pattern": "secrets?/" },
{ "pattern": "\\.pem$" },
{ "pattern": "\\.key$" },
],
},
"delete_path": {
"default_mode": "confirm",
"always_deny": [
// System directories
{ "pattern": "^/etc" },
{ "pattern": "^/usr" },
{ "pattern": "^/bin" },
{ "pattern": "^/sbin" },
{ "pattern": "^/var" },
{ "pattern": "^/boot" },
{ "pattern": "^/root" },
// Home directory root
{ "pattern": "^~$" },
{ "pattern": "^/Users/[^/]+$" },
{ "pattern": "^/home/[^/]+$" },
// Git directory
{ "pattern": "\\.git/?$" },
// Windows system directories
{ "pattern": "^C:\\\\Windows" },
{ "pattern": "^C:\\\\Program Files" },
],
},
"fetch": {
"default_mode": "confirm",
"always_allow": [
// Common documentation sites
{ "pattern": "^https://(docs\\.|api\\.)?github\\.com" },
{ "pattern": "^https://docs\\.rs" },
{ "pattern": "^https://crates\\.io" },
],
},
},
},
// When enabled, agent edits will be displayed in single-file editors for review
"single_file_review": true,
// When enabled, show voting thumbs for feedback on agent edits.

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@ -20,7 +20,9 @@ convert_case.workspace = true
fs.workspace = true
gpui.workspace = true
language_model.workspace = true
log.workspace = true
project.workspace = true
regex.workspace = true
schemars.workspace = true
serde.workspace = true
settings.workspace = true

View file

@ -11,7 +11,7 @@ use schemars::JsonSchema;
use serde::{Deserialize, Serialize};
use settings::{
DefaultAgentView, DockPosition, DockSide, LanguageModelParameters, LanguageModelSelection,
NotifyWhenAgentWaiting, RegisterSetting, Settings,
NotifyWhenAgentWaiting, RegisterSetting, Settings, ToolPermissionMode,
};
pub use crate::agent_profile::*;
@ -49,6 +49,7 @@ pub struct AgentSettings {
pub expand_terminal_card: bool,
pub use_modifier_to_send: bool,
pub message_editor_min_lines: usize,
pub tool_permissions: ToolPermissions,
}
impl AgentSettings {
@ -155,6 +156,68 @@ impl Default for AgentProfileId {
}
}
#[derive(Clone, Debug, Default)]
pub struct ToolPermissions {
pub tools: collections::HashMap<Arc<str>, ToolRules>,
}
#[derive(Clone, Debug)]
pub struct ToolRules {
pub default_mode: ToolPermissionMode,
pub always_allow: Vec<CompiledRegex>,
pub always_deny: Vec<CompiledRegex>,
pub always_confirm: Vec<CompiledRegex>,
}
impl Default for ToolRules {
fn default() -> Self {
Self {
default_mode: ToolPermissionMode::Confirm,
always_allow: Vec::new(),
always_deny: Vec::new(),
always_confirm: Vec::new(),
}
}
}
#[derive(Clone)]
pub struct CompiledRegex {
pub pattern: String,
pub case_sensitive: bool,
pub regex: regex::Regex,
}
impl std::fmt::Debug for CompiledRegex {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("CompiledRegex")
.field("pattern", &self.pattern)
.field("case_sensitive", &self.case_sensitive)
.finish()
}
}
impl CompiledRegex {
pub fn new(pattern: &str, case_sensitive: bool) -> Option<Self> {
let regex = regex::RegexBuilder::new(pattern)
.case_insensitive(!case_sensitive)
.build()
.map_err(|e| {
log::warn!("Invalid regex pattern '{}': {}", pattern, e);
e
})
.ok()?;
Some(Self {
pattern: pattern.to_string(),
case_sensitive,
regex,
})
}
pub fn is_match(&self, input: &str) -> bool {
self.regex.is_match(input)
}
}
impl Settings for AgentSettings {
fn from_settings(content: &settings::SettingsContent) -> Self {
let agent = content.agent.clone().unwrap();
@ -193,6 +256,467 @@ impl Settings for AgentSettings {
expand_terminal_card: agent.expand_terminal_card.unwrap(),
use_modifier_to_send: agent.use_modifier_to_send.unwrap(),
message_editor_min_lines: agent.message_editor_min_lines.unwrap(),
tool_permissions: compile_tool_permissions(agent.tool_permissions),
}
}
}
fn compile_tool_permissions(content: Option<settings::ToolPermissionsContent>) -> ToolPermissions {
let Some(content) = content else {
return ToolPermissions::default();
};
let tools = content
.tools
.into_iter()
.map(|(tool_name, rules_content)| {
let rules = ToolRules {
default_mode: rules_content.default_mode.unwrap_or_default(),
always_allow: rules_content
.always_allow
.map(|v| compile_regex_rules(v.0))
.unwrap_or_default(),
always_deny: rules_content
.always_deny
.map(|v| compile_regex_rules(v.0))
.unwrap_or_default(),
always_confirm: rules_content
.always_confirm
.map(|v| compile_regex_rules(v.0))
.unwrap_or_default(),
};
(tool_name, rules)
})
.collect();
ToolPermissions { tools }
}
fn compile_regex_rules(rules: Vec<settings::ToolRegexRule>) -> Vec<CompiledRegex> {
rules
.into_iter()
.filter_map(|rule| CompiledRegex::new(&rule.pattern, rule.case_sensitive.unwrap_or(false)))
.collect()
}
#[cfg(test)]
mod tests {
use super::*;
use serde_json::json;
use settings::ToolPermissionsContent;
#[test]
fn test_compiled_regex_case_insensitive() {
let regex = CompiledRegex::new("rm\\s+-rf", false).unwrap();
assert!(regex.is_match("rm -rf /"));
assert!(regex.is_match("RM -RF /"));
assert!(regex.is_match("Rm -Rf /"));
}
#[test]
fn test_compiled_regex_case_sensitive() {
let regex = CompiledRegex::new("DROP\\s+TABLE", true).unwrap();
assert!(regex.is_match("DROP TABLE users"));
assert!(!regex.is_match("drop table users"));
}
#[test]
fn test_invalid_regex_returns_none() {
let result = CompiledRegex::new("[invalid(regex", false);
assert!(result.is_none());
}
#[test]
fn test_tool_permissions_parsing() {
let json = json!({
"tools": {
"terminal": {
"default_mode": "allow",
"always_deny": [
{ "pattern": "rm\\s+-rf" }
],
"always_allow": [
{ "pattern": "^git\\s" }
]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal_rules = permissions.tools.get("terminal").unwrap();
assert_eq!(terminal_rules.default_mode, ToolPermissionMode::Allow);
assert_eq!(terminal_rules.always_deny.len(), 1);
assert_eq!(terminal_rules.always_allow.len(), 1);
assert!(terminal_rules.always_deny[0].is_match("rm -rf /"));
assert!(terminal_rules.always_allow[0].is_match("git status"));
}
#[test]
fn test_tool_rules_default_mode() {
let json = json!({
"tools": {
"edit_file": {
"default_mode": "deny"
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let rules = permissions.tools.get("edit_file").unwrap();
assert_eq!(rules.default_mode, ToolPermissionMode::Deny);
}
#[test]
fn test_tool_permissions_empty() {
let permissions = compile_tool_permissions(None);
assert!(permissions.tools.is_empty());
}
#[test]
fn test_tool_rules_default_returns_confirm() {
let default_rules = ToolRules::default();
assert_eq!(default_rules.default_mode, ToolPermissionMode::Confirm);
assert!(default_rules.always_allow.is_empty());
assert!(default_rules.always_deny.is_empty());
assert!(default_rules.always_confirm.is_empty());
}
#[test]
fn test_tool_permissions_with_multiple_tools() {
let json = json!({
"tools": {
"terminal": {
"default_mode": "allow",
"always_deny": [{ "pattern": "rm\\s+-rf" }]
},
"edit_file": {
"default_mode": "confirm",
"always_deny": [{ "pattern": "\\.env$" }]
},
"delete_path": {
"default_mode": "deny"
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
assert_eq!(permissions.tools.len(), 3);
let terminal = permissions.tools.get("terminal").unwrap();
assert_eq!(terminal.default_mode, ToolPermissionMode::Allow);
assert_eq!(terminal.always_deny.len(), 1);
let edit_file = permissions.tools.get("edit_file").unwrap();
assert_eq!(edit_file.default_mode, ToolPermissionMode::Confirm);
assert!(edit_file.always_deny[0].is_match("secrets.env"));
let delete_path = permissions.tools.get("delete_path").unwrap();
assert_eq!(delete_path.default_mode, ToolPermissionMode::Deny);
}
#[test]
fn test_tool_permissions_with_all_rule_types() {
let json = json!({
"tools": {
"terminal": {
"always_deny": [{ "pattern": "rm\\s+-rf" }],
"always_confirm": [{ "pattern": "sudo\\s" }],
"always_allow": [{ "pattern": "^git\\s+status" }]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert_eq!(terminal.always_deny.len(), 1);
assert_eq!(terminal.always_confirm.len(), 1);
assert_eq!(terminal.always_allow.len(), 1);
assert!(terminal.always_deny[0].is_match("rm -rf /"));
assert!(terminal.always_confirm[0].is_match("sudo apt install"));
assert!(terminal.always_allow[0].is_match("git status"));
}
#[test]
fn test_invalid_regex_is_skipped_not_fail() {
let json = json!({
"tools": {
"terminal": {
"always_deny": [
{ "pattern": "[invalid(regex" },
{ "pattern": "valid_pattern" }
]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert_eq!(terminal.always_deny.len(), 1);
assert!(terminal.always_deny[0].is_match("valid_pattern"));
}
#[test]
fn test_default_json_tool_permissions_parse() {
let default_json = include_str!("../../../assets/settings/default.json");
let value: serde_json::Value = serde_json_lenient::from_str(default_json)
.expect("default.json should be valid JSON with comments");
let agent = value
.get("agent")
.expect("default.json should have 'agent' key");
let tool_permissions = agent
.get("tool_permissions")
.expect("agent should have 'tool_permissions' key");
let content: ToolPermissionsContent = serde_json::from_value(tool_permissions.clone())
.expect("tool_permissions should parse into ToolPermissionsContent");
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions
.tools
.get("terminal")
.expect("terminal tool should be configured");
assert!(
!terminal.always_deny.is_empty(),
"terminal should have deny rules"
);
assert!(
!terminal.always_confirm.is_empty(),
"terminal should have confirm rules"
);
assert!(
!terminal.always_allow.is_empty(),
"terminal should have allow rules"
);
let edit_file = permissions
.tools
.get("edit_file")
.expect("edit_file tool should be configured");
assert!(
!edit_file.always_deny.is_empty(),
"edit_file should have deny rules"
);
let delete_path = permissions
.tools
.get("delete_path")
.expect("delete_path tool should be configured");
assert!(
!delete_path.always_deny.is_empty(),
"delete_path should have deny rules"
);
let fetch = permissions
.tools
.get("fetch")
.expect("fetch tool should be configured");
assert!(
!fetch.always_allow.is_empty(),
"fetch should have allow rules"
);
}
#[test]
fn test_default_deny_rules_match_dangerous_commands() {
let default_json = include_str!("../../../assets/settings/default.json");
let value: serde_json::Value = serde_json_lenient::from_str(default_json).unwrap();
let tool_permissions = value["agent"]["tool_permissions"].clone();
let content: ToolPermissionsContent = serde_json::from_value(tool_permissions).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
let dangerous_commands = [
"rm -rf /",
"rm -rf ~",
"rm -rf ..",
"mkfs.ext4 /dev/sda",
"dd if=/dev/zero of=/dev/sda",
"cat /etc/passwd",
"cat /etc/shadow",
"del /f /s /q c:\\",
"format c:",
"rd /s /q c:\\windows",
];
for cmd in &dangerous_commands {
assert!(
terminal.always_deny.iter().any(|r| r.is_match(cmd)),
"Command '{}' should be blocked by deny rules",
cmd
);
}
}
#[test]
fn test_default_allow_rules_match_safe_commands() {
let default_json = include_str!("../../../assets/settings/default.json");
let value: serde_json::Value = serde_json_lenient::from_str(default_json).unwrap();
let tool_permissions = value["agent"]["tool_permissions"].clone();
let content: ToolPermissionsContent = serde_json::from_value(tool_permissions).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
let safe_commands = [
"cargo build",
"cargo test",
"cargo check",
"npm test",
"pnpm install",
"yarn run build",
"ls",
"ls -la",
"cat file.txt",
"git status",
"git log",
"git diff",
];
for cmd in &safe_commands {
assert!(
terminal.always_allow.iter().any(|r| r.is_match(cmd)),
"Command '{}' should be allowed by allow rules",
cmd
);
}
}
#[test]
fn test_deny_takes_precedence_over_allow_and_confirm() {
let json = json!({
"tools": {
"terminal": {
"default_mode": "allow",
"always_deny": [{ "pattern": "dangerous" }],
"always_confirm": [{ "pattern": "dangerous" }],
"always_allow": [{ "pattern": "dangerous" }]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert!(
terminal.always_deny[0].is_match("run dangerous command"),
"Deny rule should match"
);
assert!(
terminal.always_allow[0].is_match("run dangerous command"),
"Allow rule should also match (but deny takes precedence at evaluation time)"
);
assert!(
terminal.always_confirm[0].is_match("run dangerous command"),
"Confirm rule should also match (but deny takes precedence at evaluation time)"
);
}
#[test]
fn test_confirm_takes_precedence_over_allow() {
let json = json!({
"tools": {
"terminal": {
"default_mode": "allow",
"always_confirm": [{ "pattern": "risky" }],
"always_allow": [{ "pattern": "risky" }]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert!(
terminal.always_confirm[0].is_match("do risky thing"),
"Confirm rule should match"
);
assert!(
terminal.always_allow[0].is_match("do risky thing"),
"Allow rule should also match (but confirm takes precedence at evaluation time)"
);
}
#[test]
fn test_regex_matches_anywhere_in_string_not_just_anchored() {
let json = json!({
"tools": {
"terminal": {
"always_deny": [
{ "pattern": "rm\\s+-rf" },
{ "pattern": "/etc/passwd" }
]
}
}
});
let content: ToolPermissionsContent = serde_json::from_value(json).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert!(
terminal.always_deny[0].is_match("echo hello && rm -rf /"),
"Should match rm -rf in the middle of a command chain"
);
assert!(
terminal.always_deny[0].is_match("cd /tmp; rm -rf *"),
"Should match rm -rf after semicolon"
);
assert!(
terminal.always_deny[1].is_match("cat /etc/passwd | grep root"),
"Should match /etc/passwd in a pipeline"
);
assert!(
terminal.always_deny[1].is_match("vim /etc/passwd"),
"Should match /etc/passwd as argument"
);
}
#[test]
fn test_fork_bomb_pattern_matches() {
let fork_bomb_regex = CompiledRegex::new(r":\(\)\{\s*:\|:&\s*\};:", false).unwrap();
assert!(
fork_bomb_regex.is_match(":(){ :|:& };:"),
"Should match the classic fork bomb"
);
assert!(
fork_bomb_regex.is_match(":(){ :|:&};:"),
"Should match fork bomb without spaces"
);
}
#[test]
fn test_default_json_fork_bomb_pattern_matches() {
let default_json = include_str!("../../../assets/settings/default.json");
let value: serde_json::Value = serde_json_lenient::from_str(default_json).unwrap();
let tool_permissions = value["agent"]["tool_permissions"].clone();
let content: ToolPermissionsContent = serde_json::from_value(tool_permissions).unwrap();
let permissions = compile_tool_permissions(Some(content));
let terminal = permissions.tools.get("terminal").unwrap();
assert!(
terminal
.always_deny
.iter()
.any(|r| r.is_match(":(){ :|:& };:")),
"Default deny rules should block the classic fork bomb"
);
}
}

View file

@ -482,6 +482,7 @@ mod tests {
expand_terminal_card: true,
use_modifier_to_send: true,
message_editor_min_lines: 1,
tool_permissions: Default::default(),
};
cx.update(|cx| {

View file

@ -24,6 +24,12 @@ impl FeatureFlag for AcpBetaFeatureFlag {
const NAME: &'static str = "acp-beta";
}
pub struct ToolPermissionsFeatureFlag;
impl FeatureFlag for ToolPermissionsFeatureFlag {
const NAME: &'static str = "tool-permissions";
}
pub struct AgentSharingFeatureFlag;
impl FeatureFlag for AgentSharingFeatureFlag {

View file

@ -3,7 +3,10 @@ use gpui::SharedString;
use schemars::{JsonSchema, json_schema};
use serde::{Deserialize, Serialize};
use settings_macros::{MergeFrom, with_fallible_options};
use std::{borrow::Cow, path::PathBuf, sync::Arc};
use std::sync::Arc;
use std::{borrow::Cow, path::PathBuf};
use crate::ExtendingVec;
use crate::{DockPosition, DockSide};
@ -119,6 +122,11 @@ pub struct AgentSettingsContent {
///
/// Default: 4
pub message_editor_min_lines: Option<usize>,
/// Per-tool permission rules for granular control over which tool actions require confirmation.
///
/// This setting only applies to the native Zed agent. External agent servers (Claude Code, Gemini CLI, etc.)
/// have their own permission systems and are not affected by these settings.
pub tool_permissions: Option<ToolPermissionsContent>,
}
impl AgentSettingsContent {
@ -466,3 +474,61 @@ pub enum CustomAgentServerSettings {
favorite_config_option_values: HashMap<String, Vec<String>>,
},
}
#[with_fallible_options]
#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, JsonSchema, MergeFrom)]
pub struct ToolPermissionsContent {
/// Per-tool permission rules.
/// Keys: terminal, edit_file, delete_path, move_path, create_directory,
/// save_file, fetch, web_search
#[serde(default)]
pub tools: HashMap<Arc<str>, ToolRulesContent>,
}
#[with_fallible_options]
#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, JsonSchema, MergeFrom)]
pub struct ToolRulesContent {
/// Default mode when no regex rules match.
/// Default: confirm
pub default_mode: Option<ToolPermissionMode>,
/// Regexes for inputs to auto-approve.
/// For terminal: matches command. For file tools: matches path. For fetch: matches URL.
/// Default: []
pub always_allow: Option<ExtendingVec<ToolRegexRule>>,
/// Regexes for inputs to auto-reject.
/// **SECURITY**: These take precedence over ALL other rules, across ALL settings layers.
/// Default: []
pub always_deny: Option<ExtendingVec<ToolRegexRule>>,
/// Regexes for inputs that must always prompt.
/// Takes precedence over always_allow but not always_deny.
/// Default: []
pub always_confirm: Option<ExtendingVec<ToolRegexRule>>,
}
#[with_fallible_options]
#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, JsonSchema, MergeFrom)]
pub struct ToolRegexRule {
/// The regex pattern to match.
pub pattern: String,
/// Whether the regex is case-sensitive.
/// Default: false (case-insensitive)
pub case_sensitive: Option<bool>,
}
#[derive(
Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize, JsonSchema, MergeFrom,
)]
#[serde(rename_all = "snake_case")]
pub enum ToolPermissionMode {
/// Auto-approve without prompting.
Allow,
/// Auto-reject with an error.
Deny,
/// Always prompt for confirmation (default behavior).
#[default]
Confirm,
}

View file

@ -1,198 +0,0 @@
# Visual Test Plan: Agent Panel Image Rendering
## 🎯 The Goal
We want a visual regression test that **catches bugs in how `read_file` displays images**.
If someone changes the code in `ReadFileTool` or the UI rendering in `thread_view.rs`, this test should fail and show us visually what changed.
## ⚠️ Current Problem: The Test is Useless
**The current test in `crates/zed/src/visual_test_runner.rs` does NOT test the real code!**
Here's what it does now (WRONG):
1. Creates a `StubAgentConnection`
2. Hard-codes a fake tool call response with pre-baked image data
3. Injects that directly into `AcpThread`
4. Takes a screenshot
**Why this is useless:** If you change how `ReadFileTool` produces its output (in `crates/agent/src/tools/read_file_tool.rs`), the test will still pass because it never runs that code! The test bypasses the entire tool execution pipeline.
## ✅ What We Actually Need
The test should:
1. Create a real project with a real image file
2. Actually run the real `ReadFileTool::run()` method
3. Let the tool produce its real output via `event_stream.update_fields()`
4. Have that real output flow through to `AcpThread` and render in the UI
5. Take a screenshot of the real rendered result
This way, if someone changes `ReadFileTool` or the UI rendering, the test will catch it.
## 📚 Architecture Background (For Newcomers)
Here's how the agent system works:
### The Two "Thread" Types
- **`Thread`** (in `crates/agent/src/thread.rs`) - Runs tools, talks to LLMs, produces events
- **`AcpThread`** (in `crates/acp_thread/src/acp_thread.rs`) - Receives events and stores data for UI rendering
### How Tools Work
1. `Thread` has registered tools (like `ReadFileTool`)
2. When a tool runs, it gets a `ToolCallEventStream`
3. The tool calls `event_stream.update_fields(...)` to send updates
4. Those updates become `ThreadEvent::ToolCallUpdate` events
5. Events flow to `AcpThread` via `handle_thread_events()` in `NativeAgentConnection`
6. `AcpThread` stores the data and the UI renders it
### The Key File Locations
- **Tool implementation:** `crates/agent/src/tools/read_file_tool.rs`
- Lines 163-188: Image file handling (calls `event_stream.update_fields()`)
- **Event stream:** `crates/agent/src/thread.rs`
- `ToolCallEventStream::update_fields()` - sends updates
- `ToolCallEventStream::test()` - creates a test event stream
- **UI rendering:** `crates/agent_ui/src/acp/thread_view.rs`
- `render_image_output()` - renders images in tool call output
- **Current (broken) test:** `crates/zed/src/visual_test_runner.rs`
- `run_agent_thread_view_test()` - the function that needs fixing
## 🔧 Implementation Plan
### Option A: Direct Tool Invocation (Recommended)
Run the real tool and capture its output:
```rust
// 1. Create a project with a real image file
let fs = FakeFs::new(cx.executor());
fs.insert_file("/project/test-image.png", EMBEDDED_TEST_IMAGE.to_vec()).await;
let project = Project::test(fs.clone(), ["/project"], cx).await;
// 2. Create the ReadFileTool (needs Thread, ActionLog)
let action_log = cx.new(|_| ActionLog::new(project.clone()));
// ... create Thread with project ...
let tool = Arc::new(ReadFileTool::new(thread.downgrade(), project.clone(), action_log));
// 3. Run the tool and capture events
let (event_stream, mut event_receiver) = ToolCallEventStream::test();
let input = ReadFileToolInput {
path: "project/test-image.png".to_string(),
start_line: None,
end_line: None,
};
tool.run(input, event_stream, cx).await?;
// 4. Collect the ToolCallUpdateFields that the tool produced
let updates = event_receiver.collect_updates();
// 5. Create an AcpThread and inject the real tool output
// ... create AcpThread ...
acp_thread.update(cx, |thread, cx| {
// First create the tool call entry
thread.upsert_tool_call(initial_tool_call, cx)?;
// Then update it with the real output from the tool
for update in updates {
thread.update_tool_call(update, cx)?;
}
})?;
// 6. Render and screenshot
```
### Required Exports
The `agent` crate needs to export these for the visual test:
- `ReadFileTool` and `ReadFileToolInput`
- `ToolCallEventStream::test()` (already has `#[cfg(feature = "test-support")]`)
- `Thread` (to create the tool)
Check `crates/agent/src/lib.rs` and add exports if needed.
### Required Dependencies in `crates/zed/Cargo.toml`
The `visual-tests` feature needs:
```toml
"agent/test-support" # For ToolCallEventStream::test() and tool exports
```
### Option B: Use NativeAgentConnection with Fake Model
Alternatively, use the full agent flow with a fake LLM:
1. Create `NativeAgentServer` with a `FakeLanguageModel`
2. Program the fake model to return a tool call for `read_file`
3. Let the real agent flow execute the tool
4. The tool runs, produces output, flows through to UI
This is more complex but tests more of the real code path.
## 📋 Step-by-Step Implementation Checklist
### Phase 1: Enable Tool Access
- [x] Add `agent/test-support` to `visual-tests` feature in `crates/zed/Cargo.toml`
- [x] Verify `ReadFileTool`, `ReadFileToolInput`, `ToolCallEventStream::test()` are exported
- [x] Added additional required features: `language_model/test-support`, `fs/test-support`, `action_log`
### Phase 2: Rewrite the Test
- [x] In `run_agent_thread_view_test()`, remove the fake stub response
- [x] Create a real temp directory with a real image file (FakeFs doesn't work in visual test runner)
- [x] Create the real `ReadFileTool` with Thread, ActionLog, etc.
- [x] Run the tool with `ToolCallEventStream::test()`
- [x] Capture the `ToolCallUpdateFields` it produces
- [x] Use the real tool output to populate the stub connection's response
### Phase 3: Verify It Works
- [x] Run `UPDATE_BASELINE=1 cargo run -p zed --bin visual_test_runner --features visual-tests`
- [x] Check the screenshot shows the real tool output
- [x] Intentionally break `read_file_tool.rs` (comment out `event_stream.update_fields`)
- [x] Verified the test fails with: "ReadFileTool did not produce any content - the tool is broken!"
- [x] Restored the code and verified test passes again
## 🧪 How to Verify the Test is Actually Testing Real Code
After implementing, do this sanity check:
1. In `crates/agent/src/tools/read_file_tool.rs`, comment out lines 181-185:
```rust
// event_stream.update_fields(ToolCallUpdateFields::new().content(vec![
// acp::ToolCallContent::Content(acp::Content::new(acp::ContentBlock::Image(
// acp::ImageContent::new(language_model_image.source.clone(), "image/png"),
// ))),
// ]));
```
2. Run the visual test - it should FAIL or produce a visibly different screenshot
3. Restore the code - test should pass again
If commenting out the real tool code doesn't affect the test, the test is still broken!
## 📁 Files Modified
| File | Change |
|------|--------|
| `crates/zed/Cargo.toml` | Added `agent/test-support`, `language_model/test-support`, `fs/test-support`, `action_log` to `visual-tests` feature |
| `crates/zed/src/visual_test_runner.rs` | Rewrote `run_agent_thread_view_test()` to run the real `ReadFileTool` and capture its output |
Note: No changes needed to `crates/agent/src/lib.rs` - all necessary exports were already public.
## ✅ Already Completed (Don't Redo These)
These changes have already been made and are working:
1. **`read_file` tool sends image content** - `crates/agent/src/tools/read_file_tool.rs` now calls `event_stream.update_fields()` with image content blocks (lines 181-185)
2. **UI renders images** - `crates/agent_ui/src/acp/thread_view.rs` has `render_image_output()` that shows dimensions ("512×512 PNG") and a "Go to File" button
3. **Image tool calls auto-expand** - The UI automatically expands tool calls that return images
4. **Visual test infrastructure exists** - The test runner, baseline comparison, etc. all work
The only thing broken is that the test doesn't actually run the real tool code!
## 🔗 Related Code References
- Tool implementation: [read_file_tool.rs](file:///Users/rtfeldman/code/zed5/crates/agent/src/tools/read_file_tool.rs)
- Event stream: [thread.rs lines 2501-2596](file:///Users/rtfeldman/code/zed5/crates/agent/src/thread.rs#L2501-L2596)
- UI rendering: [thread_view.rs render_image_output](file:///Users/rtfeldman/code/zed5/crates/agent_ui/src/acp/thread_view.rs#L3146-L3217)
- Current test: [visual_test_runner.rs run_agent_thread_view_test](file:///Users/rtfeldman/code/zed5/crates/zed/src/visual_test_runner.rs#L778-L943)

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@ -1,661 +0,0 @@
# Visual Test Runner Improvements
This document describes improvements to make the visual test runner in `crates/zed/src/visual_test_runner.rs` more deterministic, faster, and less hacky.
## Background
The visual test runner captures screenshots of Zed's UI and compares them against baseline images. It currently works but has several issues:
1. **Non-deterministic timing**: Uses `timer().await` calls scattered throughout
2. **Real filesystem I/O**: Uses `tempfile` and `RealFs` instead of `FakeFs`
3. **Dead code**: Unused variables and counters from removed print statements
4. **Code duplication**: Similar setup code repeated across tests
5. **Limited production code coverage**: Some areas use stubs where real code could run
## How to Run the Visual Tests
```bash
# Run the visual tests (compare against baselines)
cargo run -p zed --bin zed_visual_test_runner --features visual-tests
# Update baseline images (when UI intentionally changes)
UPDATE_BASELINE=1 cargo run -p zed --bin zed_visual_test_runner --features visual-tests
```
The test runner is a separate binary, not a `#[test]` function. It uses `Application::new().run()` to create a real GPUI application context.
---
## Improvement 1: Replace Timer-Based Waits with `run_until_parked()`
### Problem
The code is littered with timing-based waits like:
```rust
cx.background_executor()
.timer(std::time::Duration::from_millis(500))
.await;
```
These appear ~15 times in the file. They are:
- **Slow**: Adds up to several seconds of unnecessary waiting
- **Non-deterministic**: Could flake on slow CI machines
- **Arbitrary**: The durations (100ms, 200ms, 300ms, 500ms, 2s) were chosen by trial and error
### Solution
Use `run_until_parked()` which runs all pending async tasks until there's nothing left to do. This is:
- **Instant**: Returns immediately when work is complete
- **Deterministic**: Waits exactly as long as needed
- **Standard**: Used throughout Zed's test suite
### How to Implement
The challenge is that the visual test runner uses `AsyncApp` (from `cx.spawn()`), not `TestAppContext`. The `run_until_parked()` method is on `BackgroundExecutor` which is accessible via `cx.background_executor()`.
However, `run_until_parked()` is a **blocking** call that runs the executor synchronously, while the visual tests are currently written as async code. You'll need to restructure the code.
**Option A: Keep async structure, call run_until_parked between awaits**
```rust
// Before:
cx.background_executor()
.timer(std::time::Duration::from_millis(500))
.await;
// After - run all pending work synchronously:
cx.background_executor().run_until_parked();
```
But this won't work directly in async context because `run_until_parked()` blocks.
**Option B: Restructure to use synchronous test pattern**
The standard Zed test pattern uses `#[gpui::test]` with `TestAppContext`:
```rust
#[gpui::test]
async fn test_something(cx: &mut TestAppContext) {
cx.run_until_parked(); // This works!
}
```
For the visual test runner, you'd need to convert from `Application::new().run()` to the test harness. This is a bigger change but would be more idiomatic.
**Option C: Use cx.refresh() + small delay for rendering**
For purely rendering-related waits, `cx.refresh()` forces a repaint. A single small delay after refresh may be acceptable for GPU readback timing:
```rust
cx.refresh().ok();
// Minimal delay just for GPU work, not async task completion
cx.background_executor()
.timer(std::time::Duration::from_millis(16)) // ~1 frame
.await;
```
### Locations to Change
Search for `timer(std::time::Duration` in the file. Each occurrence should be evaluated:
| Line | Current Duration | Purpose | Replacement |
|------|-----------------|---------|-------------|
| 160-162 | 500ms | Wait for worktree | `run_until_parked()` or await the task |
| 190-192 | 500ms | Wait for panel add | `run_until_parked()` |
| 205-207 | 500ms | Wait for panel render | `cx.refresh()` |
| 248-250 | 500ms | Wait for item activation | `run_until_parked()` |
| 258-260 | 2000ms | Wait for UI to stabilize | `cx.refresh()` + minimal delay |
| 294-296 | 500ms | Wait for panel close | `run_until_parked()` |
| 752-754 | 100ms | Wait for worktree scan | `run_until_parked()` |
| 860-862 | 100ms | Wait for workspace init | `run_until_parked()` |
| 881-883 | 200ms | Wait for panel ready | `run_until_parked()` |
| 893-895 | 200ms | Wait for thread view | `run_until_parked()` |
| 912-914 | 500ms | Wait for response | `run_until_parked()` |
| 937-939 | 300ms | Wait for refresh | `cx.refresh()` |
| 956-958 | 300ms | Wait for UI update | `run_until_parked()` |
| 968-970 | 300ms | Wait for refresh | `cx.refresh()` |
### How to Verify
After making changes:
1. Run the tests: `cargo run -p zed --bin zed_visual_test_runner --features visual-tests`
2. They should pass with the same baseline images
3. They should run faster (measure before/after)
---
## Improvement 2: Use `FakeFs` Instead of Real Filesystem
### Problem
The code currently uses:
```rust
let fs = Arc::new(RealFs::new(None, cx.background_executor().clone()));
let temp_dir = tempfile::tempdir().expect("Failed to create temp directory");
```
This is:
- **Slow**: Real I/O is slower than in-memory operations
- **Non-deterministic**: Filesystem timing varies
- **Messy**: Leaves temp directories on failure
### Solution
Use `FakeFs` which is an in-memory filesystem used throughout Zed's tests:
```rust
use fs::FakeFs;
let fs = FakeFs::new(cx.background_executor().clone());
fs.insert_tree(
"/project",
json!({
"src": {
"main.rs": "fn main() { println!(\"Hello\"); }"
},
"Cargo.toml": "[package]\nname = \"test\""
}),
).await;
```
### How to Implement
1. **Add the dependency** in `crates/zed/Cargo.toml` if not present:
```toml
fs = { workspace = true, features = ["test-support"] }
```
2. **Replace RealFs creation** in `init_app_state()` (around line 655):
```rust
// Before:
let fs = Arc::new(RealFs::new(None, cx.background_executor().clone()));
// After:
let fs = FakeFs::new(cx.background_executor().clone());
```
3. **Replace tempdir + file creation** (around lines 66-71 and 518-643):
```rust
// Before:
let temp_dir = tempfile::tempdir().expect("...");
let project_path = temp_dir.path().join("project");
std::fs::create_dir_all(&project_path).expect("...");
create_test_files(&project_path);
// After:
let fs = FakeFs::new(cx.background_executor().clone());
fs.insert_tree("/project", json!({
"src": {
"main.rs": include_str!("test_content/main.rs"),
"lib.rs": include_str!("test_content/lib.rs"),
},
"Cargo.toml": include_str!("test_content/Cargo.toml"),
"README.md": include_str!("test_content/README.md"),
})).await;
let project_path = Path::new("/project");
```
4. **For the test image** (around line 726):
```rust
// Before:
let temp_dir = tempfile::tempdir()?;
let project_path = temp_dir.path().join("project");
std::fs::create_dir_all(&project_path)?;
let image_path = project_path.join("test-image.png");
std::fs::write(&image_path, EMBEDDED_TEST_IMAGE)?;
// After:
fs.insert_file("/project/test-image.png", EMBEDDED_TEST_IMAGE.to_vec()).await;
let project_path = Path::new("/project");
```
5. **Update `init_app_state`** to accept `fs` as a parameter instead of creating it internally.
### Reference Example
See `crates/project_panel/src/project_panel_tests.rs` lines 17-62 for a complete example of using `FakeFs` with `insert_tree()`.
### How to Verify
1. Run the tests - they should produce identical screenshots
2. Verify no temp directories are created in `/tmp` or equivalent
3. Check that tests run faster
---
## Improvement 3: Remove Dead Code
### Problem
After removing print statements, there's leftover dead code:
```rust
let _ = update_baseline; // Line 63 - was used in removed print
let mut passed = 0; // Lines 263-265
let mut failed = 0;
let mut updated = 0;
// ... counters incremented but never read
let _ = (passed, updated); // Line 327 - silences warning
```
### Solution
Remove the unused code and restructure to not need counters.
### How to Implement
1. **Remove the `let _ = update_baseline;`** on line 63 - `update_baseline` is already used later
2. **Simplify test result handling**:
```rust
// Before:
let mut passed = 0;
let mut failed = 0;
let mut updated = 0;
match test_result {
Ok(TestResult::Passed) => passed += 1,
Ok(TestResult::BaselineUpdated(_)) => updated += 1,
Err(_) => failed += 1,
}
// ... repeat for each test ...
let _ = (passed, updated);
if failed > 0 {
std::process::exit(1);
}
// After:
let mut any_failed = false;
if run_visual_test("project_panel", ...).await.is_err() {
any_failed = true;
}
if run_visual_test("workspace_with_editor", ...).await.is_err() {
any_failed = true;
}
if run_agent_thread_view_test(...).await.is_err() {
any_failed = true;
}
if any_failed {
std::process::exit(1);
}
```
3. **Or collect results into a Vec**:
```rust
let results = vec![
run_visual_test("project_panel", ...).await,
run_visual_test("workspace_with_editor", ...).await,
run_agent_thread_view_test(...).await,
];
if results.iter().any(|r| r.is_err()) {
std::process::exit(1);
}
```
### How to Verify
1. Run `cargo clippy -p zed --features visual-tests` - should have no warnings about unused variables
2. Run the tests - behavior should be unchanged
---
## Improvement 4: Consolidate Test Setup Code
### Problem
There's significant duplication between:
- Main workspace test setup (lines 106-260)
- Agent panel test setup (lines 713-900)
Both create:
- Projects with `Project::local()`
- Worktrees with `find_or_create_worktree()`
- Windows with `cx.open_window()`
- Wait for things to settle
### Solution
Extract common setup into helper functions.
### How to Implement
1. **Create a `TestWorkspace` struct**:
```rust
struct TestWorkspace {
window: WindowHandle<Workspace>,
project: Entity<Project>,
}
impl TestWorkspace {
async fn new(
app_state: Arc<AppState>,
size: Size<Pixels>,
project_path: &Path,
cx: &mut AsyncApp,
) -> Result<Self> {
let project = cx.update(|cx| {
Project::local(
app_state.client.clone(),
app_state.node_runtime.clone(),
app_state.user_store.clone(),
app_state.languages.clone(),
app_state.fs.clone(),
None,
false,
cx,
)
})?;
// Add worktree
let add_task = project.update(cx, |project, cx| {
project.find_or_create_worktree(project_path, true, cx)
})?;
add_task.await?;
// Create window
let bounds = Bounds {
origin: point(px(0.0), px(0.0)),
size,
};
let window = cx.update(|cx| {
cx.open_window(
WindowOptions {
window_bounds: Some(WindowBounds::Windowed(bounds)),
focus: false,
show: false,
..Default::default()
},
|window, cx| {
cx.new(|cx| {
Workspace::new(None, project.clone(), app_state.clone(), window, cx)
})
},
)
})??;
cx.background_executor().run_until_parked();
Ok(Self { window, project })
}
}
```
2. **Create a `setup_project_panel` helper**:
```rust
async fn setup_project_panel(
workspace: &TestWorkspace,
cx: &mut AsyncApp,
) -> Result<Entity<ProjectPanel>> {
let panel_task = workspace.window.update(cx, |_ws, window, cx| {
let weak = cx.weak_entity();
window.spawn(cx, async move |cx| ProjectPanel::load(weak, cx).await)
})?;
let panel = panel_task.await?;
workspace.window.update(cx, |ws, window, cx| {
ws.add_panel(panel.clone(), window, cx);
ws.open_panel::<ProjectPanel>(window, cx);
})?;
cx.background_executor().run_until_parked();
Ok(panel)
}
```
3. **Use helpers in tests**:
```rust
// Test 1
let workspace = TestWorkspace::new(
app_state.clone(),
size(px(1280.0), px(800.0)),
&project_path,
&mut cx,
).await?;
setup_project_panel(&workspace, &mut cx).await?;
open_file(&workspace, "src/main.rs", &mut cx).await?;
run_visual_test("project_panel", workspace.window.into(), &mut cx, update_baseline).await?;
```
### How to Verify
1. Tests should produce identical screenshots
2. Code should be shorter and more readable
3. Adding new tests should be easier
---
## Improvement 5: Exercise More Production Code
### Problem
Some tests use minimal stubs where real production code could run deterministically.
### Current State (Good)
The agent thread test already runs the **real** `ReadFileTool`:
```rust
let tool = Arc::new(agent::ReadFileTool::new(...));
tool.clone().run(input, event_stream, cx).await?;
```
This is great! It exercises real tool execution.
### Opportunities for More Coverage
1. **Syntax highlighting**: Register real language grammars so the editor shows colored code
```rust
// Currently just:
let languages = Arc::new(LanguageRegistry::new(cx.background_executor().clone()));
// Could add:
languages.register_native_grammars([
tree_sitter_rust::LANGUAGE.into(),
tree_sitter_markdown::LANGUAGE.into(),
]);
```
2. **File icons**: The project panel could show real file icons by registering file types
3. **Theme loading**: Currently uses `LoadThemes::JustBase`. Could load a full theme:
```rust
theme::init(theme::LoadThemes::All, cx);
```
(But this might make tests slower - evaluate trade-off)
4. **More tool types**: Test other tools like `ListFilesTool`, `GrepTool` that don't need network
### How to Implement Syntax Highlighting
1. Add language dependencies to `Cargo.toml`:
```toml
tree-sitter-rust = { workspace = true }
tree-sitter-markdown = { workspace = true }
```
2. In `init_app_state` or test setup:
```rust
let languages = Arc::new(LanguageRegistry::new(cx.background_executor().clone()));
// Register Rust grammar
languages.register_native_grammars([
("rust", tree_sitter_rust::LANGUAGE.into()),
]);
// Register the Rust language config
languages.register_available_language(
LanguageConfig {
name: "Rust".into(),
grammar: Some("rust".into()),
matcher: LanguageMatcher {
path_suffixes: vec!["rs".into()],
..Default::default()
},
..Default::default()
},
tree_sitter_rust::LANGUAGE.into(),
vec![], // No LSP adapters needed for visual tests
);
```
### How to Verify
1. Update baselines after adding syntax highlighting
2. Screenshots should show colored code instead of plain text
3. Tests should still be deterministic (same colors every time)
---
## Improvement 6: Better Test Organization
### Problem
Tests are numbered in comments but the structure is ad-hoc:
```rust
// Run Test 1: Project Panel
// Run Test 2: Workspace with Editor
// Run Test 3: Agent Thread View
```
### Solution
Create a test registry or use a more structured approach.
### How to Implement
1. **Define tests as structs**:
```rust
trait VisualTest {
fn name(&self) -> &'static str;
async fn setup(&self, cx: &mut AsyncApp) -> Result<AnyWindowHandle>;
async fn run(&self, window: AnyWindowHandle, cx: &mut AsyncApp, update_baseline: bool) -> Result<TestResult>;
}
struct ProjectPanelTest;
struct WorkspaceEditorTest;
struct AgentThreadTest;
impl VisualTest for ProjectPanelTest {
fn name(&self) -> &'static str { "project_panel" }
// ...
}
```
2. **Run all tests from a registry**:
```rust
let tests: Vec<Box<dyn VisualTest>> = vec![
Box::new(ProjectPanelTest),
Box::new(WorkspaceEditorTest),
Box::new(AgentThreadTest),
];
let mut failed = false;
for test in tests {
match test.run(...).await {
Ok(_) => {},
Err(_) => failed = true,
}
}
```
This makes it easy to:
- Add new tests (just add to the vec)
- Run specific tests (filter by name)
- See all tests in one place
---
## Improvement 7: Constants and Configuration
### Problem
Magic numbers scattered throughout:
```rust
size(px(1280.0), px(800.0)) // Window size for workspace tests
size(px(500.0), px(900.0)) // Window size for agent panel
Duration::from_millis(500) // Various delays
const MATCH_THRESHOLD: f64 = 0.99; // Already a constant, good!
```
### Solution
Move all configuration to constants at the top of the file.
### How to Implement
```rust
// Window sizes
const WORKSPACE_WINDOW_SIZE: Size<Pixels> = size(px(1280.0), px(800.0));
const AGENT_PANEL_WINDOW_SIZE: Size<Pixels> = size(px(500.0), px(900.0));
// Timing (if any delays are still needed after Improvement 1)
const FRAME_DELAY: Duration = Duration::from_millis(16);
// Image comparison
const MATCH_THRESHOLD: f64 = 0.99;
const PIXEL_TOLERANCE: i16 = 2; // Currently hardcoded in pixels_are_similar()
```
---
## Summary: Recommended Order of Implementation
1. **Remove dead code** (Improvement 3) - Quick win, low risk
2. **Add constants** (Improvement 7) - Quick win, improves readability
3. **Use FakeFs** (Improvement 2) - Medium effort, big determinism win
4. **Replace timers** (Improvement 1) - Medium effort, biggest determinism win
5. **Consolidate setup** (Improvement 4) - Medium effort, maintainability win
6. **Exercise more production code** (Improvement 5) - Lower priority, nice to have
7. **Better test organization** (Improvement 6) - Lower priority, nice to have for many tests
## Testing Your Changes
After each change:
```bash
# Build to check for compile errors
cargo build -p zed --features visual-tests
# Run clippy for warnings
cargo clippy -p zed --features visual-tests
# Run the tests
cargo run -p zed --bin zed_visual_test_runner --features visual-tests
# If screenshots changed intentionally, update baselines
UPDATE_BASELINE=1 cargo run -p zed --bin zed_visual_test_runner --features visual-tests
```
Baseline images are stored in `crates/zed/test_fixtures/visual_tests/`.
## Questions?
If you get stuck:
1. Look at existing tests in `crates/project_panel/src/project_panel_tests.rs` for examples of `FakeFs` and `run_until_parked()`
2. Look at `crates/gpui/src/app/test_context.rs` for `VisualTestContext` documentation
3. The CLAUDE.md file at the repo root has Rust coding guidelines