Remove dead IsStdoutTerminal() and simplify containsAny test helper

[Copilot]

Two quick-win cleanups from the golang.org/x/term module review.

Changes

• internal/tty/tty.go: Remove IsStdoutTerminal() — exported but never called anywhere in the project. IsStderrTerminal() (used by the logger) is retained.

• internal/tty/container_test.go: Replace hand-rolled substring search in the containsAny helper with strings.Contains:

// Before: manual nested loop
func containsAny(s string, substrings []string) bool {
    for _, substr := range substrings {
        if len(s) >= len(substr) {
            for i := 0; i <= len(s)-len(substr); i++ {
                if s[i:i+len(substr)] == substr {
                    return true
                }
            }
        }
    }
    return false
}

// After: standard library
func containsAny(s string, substrings []string) bool {
    for _, substr := range substrings {
        if strings.Contains(s, substr) {
            return true
        }
    }
    return false
}

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• example.com
  • Triggering command: /tmp/go-build609076577/b298/launcher.test /tmp/go-build609076577/b298/launcher.test -test.testlogfile=/tmp/go-build609076577/b298/testlog.txt -test.paniconexit0 -test.timeout=10m0s -test.v=true 64/src/runtime/cgo 64/src/internal/fmtsort/sort.go x_amd64/compile user.name 7533934/b010/ (dns block)
• invalid-host-that-does-not-exist-12345.com
  • Triggering command: /tmp/go-build609076577/b280/config.test /tmp/go-build609076577/b280/config.test -test.testlogfile=/tmp/go-build609076577/b280/testlog.txt -test.paniconexit0 -test.timeout=10m0s -test.v=true 64/src/runtime/cgo 40tls/fipstls.go ache/go/1.25.7/x64/pkg/tool/linu-o credential.helpe/opt/hostedtoolcache/go/1.25.7/x64/pkg/tool/linux_amd64/vet (dns block)
• nonexistent.local
  • Triggering command: /tmp/go-build609076577/b298/launcher.test /tmp/go-build609076577/b298/launcher.test -test.testlogfile=/tmp/go-build609076577/b298/testlog.txt -test.paniconexit0 -test.timeout=10m0s -test.v=true 64/src/runtime/cgo 64/src/internal/fmtsort/sort.go x_amd64/compile user.name 7533934/b010/ (dns block)
• slow.example.com
  • Triggering command: /tmp/go-build609076577/b298/launcher.test /tmp/go-build609076577/b298/launcher.test -test.testlogfile=/tmp/go-build609076577/b298/testlog.txt -test.paniconexit0 -test.timeout=10m0s -test.v=true 64/src/runtime/cgo 64/src/internal/fmtsort/sort.go x_amd64/compile user.name 7533934/b010/ (dns block)
• this-host-does-not-exist-12345.com
  • Triggering command: /tmp/go-build609076577/b307/mcp.test /tmp/go-build609076577/b307/mcp.test -test.testlogfile=/tmp/go-build609076577/b307/testlog.txt -test.paniconexit0 -test.timeout=10m0s -test.v=true arm.go --local x_amd64/compile user.name /gc (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[go-fan] Go Module Review: golang.org/x/term</issue_title>
<issue_description># 🐹 Go Fan Report: golang.org/x/term

Module Overview

golang.org/x/term is the official Go extended library for cross-platform terminal handling. It provides terminal detection, mode switching (raw mode), terminal sizing, password reading, and a full line-editing terminal emulator. It supports Linux, macOS, Windows, and Plan9.

Current Usage in gh-aw

The module is used exclusively through the thin internal/tty wrapper package.

• Files: 1 file imports the module (internal/tty/tty.go)
• Import count: 1 direct import
• Key APIs Used:
  • term.IsTerminal(int(os.Stderr.Fd())) — checks stderr is a TTY, used at init in internal/logger/logger.go to enable ANSI color output
  • term.IsTerminal(int(os.Stdout.Fd())) — defined as IsStdoutTerminal() in the tty package but never called anywhere in the project

Research Findings

golang.org/x/term v0.38.0 is the current version in use. The most recent activity (Feb 11, 2026) was a routine Go directive update to 1.25.0 — no new user-facing APIs were added. The module API has been stable for years.

Available APIs (not yet used)

API	Description
GetSize(fd int)	Returns terminal width and height
ReadPassword(fd int)	Reads a password without echo
MakeRaw(fd int)	Puts terminal in raw mode
Restore(fd int, state)	Restores terminal state
NewTerminal(rw, prompt)	Full line-editing terminal emulator

Best Practices

• Wrapping golang.org/x/term in an internal package (as this project does in internal/tty) is the recommended approach — it prevents the dependency from spreading throughout the codebase and makes it easy to mock/test.
• The int(os.Stderr.Fd()) cast pattern is idiomatic and correct.

Improvement Opportunities

🏃 Quick Wins

1. Remove dead code: IsStdoutTerminal()

   • IsStdoutTerminal() in internal/tty/tty.go (line 13) is never called anywhere in the project.
   • Either add a caller or remove this exported function.
   • Dead exported functions in internal packages create confusion about intent.

2. Simplify containsAny test helper in container_test.go

   • The containsAny helper (lines 313–325) reimplements substring search with a manual nested loop:

     for i := 0; i <= len(s)-len(substr); i++ {
         if s[i:i+len(substr)] == substr {
             return true
         }
     }

   • This should use strings.Contains from the standard library, which is simpler, more readable, and better optimized:

     func containsAny(s string, substrings []string) bool {
         for _, substr := range substrings {
             if strings.Contains(s, substr) {
                 return true
             }
         }
         return false
     }

✨ Feature Opportunities

3. Terminal width-aware log output

   • term.GetSize(int(os.Stderr.Fd())) could be used in the logger to adapt log line width to the terminal width.
   • Currently, the logger enables/disables color based on TTY detection but never adapts output width. Long debug lines could be wrapped or truncated at the terminal width for better readability.

4. Password/secret prompting at startup

   • If the gateway ever needs to prompt users interactively for API keys or credentials (e.g., when running without a config file), term.ReadPassword() is already available via the existing dependency at zero extra cost.

📐 Best Practice Alignment

• ✅ Wrapping in internal/tty is correct and idiomatic
• ✅ int(os.Fd()) cast pattern is standard
• ⚠️ IsStdoutTerminal() exported but unused — either use it or remove it
• ⚠️ Test helper containsAny should use strings.Contains

🔧 General Improvements

The internal/tty package currently mixes two concerns: terminal detection (tty.go) and container detection (container.go). These could eventually be split into separate focused packages (internal/tty and internal/container), but this is low priority since the package is small.

Recommendations

1. [High Priority] Remove or add a caller for IsStdoutTerminal() — dead exported code is confusing
2. [Medium Priority] Replace containsAny manual loop with strings.Contains — simpler and more standard
3. [Low Priority] Consider term.GetSize() for terminal-width-aware formatting in the logger

Next Steps

• Decide whether IsStdoutTerminal() should be removed or used somewhere (e.g., in a future stdout color detection path)
• Update containsAny test helper to use strings.Contains

---

Generated by Go Fan 🐹
Module summary saved to: /tmp/gh-aw/agent/term-module-summary.md (workspace write permission not available for specs/mods/)
Run: §22476915418

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• Fixes [go-fan] Go Module Review: golang.org/x/term #1459

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[Copilot]

Pull request overview

Removes unused terminal-detection API from the internal TTY wrapper and simplifies a test helper by using the standard library, aligning with the recent golang.org/x/term module review findings.

Changes:

• Removed dead exported function IsStdoutTerminal() from internal/tty.
• Simplified containsAny test helper to use strings.Contains.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
internal/tty/tty.go	Removes unused exported stdout TTY helper, leaving stderr TTY detection intact.
internal/tty/container_test.go	Replaces manual substring search logic in containsAny with strings.Contains.

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