Replace custom stringsTrim with strings.TrimSpace

Remove duplicate stringsTrim implementations in stats and tmux packages,
replacing all call sites with the standard library strings.TrimSpace.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

4 files changed, 14 insertions, 43 deletions

diff --git a/internal/stats/stats.go b/internal/stats/stats.go
index 4b05617..939e1aa 100644
--- a/internal/stats/stats.go
+++ b/internal/stats/stats.go
@@ -13,6 +13,7 @@ import (
 	"os"
 	"path/filepath"
 	"strconv"
+	"strings"
 	"sync/atomic"
 	"time"
 )
@@ -264,7 +265,7 @@ func TakeSnapshot() (Snapshot, error) {
 
 // CacheDir resolves the cache directory for stats.
 func CacheDir() (string, error) {
-	if x := os.Getenv("XDG_CACHE_HOME"); stringsTrim(x) != "" {
+	if x := os.Getenv("XDG_CACHE_HOME"); strings.TrimSpace(x) != "" {
 		return filepath.Join(x, "hexai"), nil
 	}
 	home, err := os.UserHomeDir()
@@ -274,22 +275,6 @@ func CacheDir() (string, error) {
 	return filepath.Join(home, ".local", "hexai", "cache"), nil
 }
 
-// stringsTrim is a tiny helper to avoid importing strings everywhere here.
-func stringsTrim(s string) string {
-	i := 0
-	j := len(s)
-	for i < j && (s[i] == ' ' || s[i] == '\t' || s[i] == '\n' || s[i] == '\r') {
-		i++
-	}
-	for j > i && (s[j-1] == ' ' || s[j-1] == '\t' || s[j-1] == '\n' || s[j-1] == '\r') {
-		j--
-	}
-	if i == 0 && j == len(s) {
-		return s
-	}
-	return s[i:j]
-}
-
 // DebugString returns a compact single-line view of a snapshot (useful for logs).
 func (s Snapshot) DebugString() string {
 	return "Σ reqs=" + strconv.FormatInt(s.Global.Reqs, 10) + " rpm=" + fmt.Sprintf("%.2f", s.RPM)
diff --git a/internal/stats/stats_test.go b/internal/stats/stats_test.go
index 75c1c5b..45f9e2a 100644
--- a/internal/stats/stats_test.go
+++ b/internal/stats/stats_test.go
@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"testing"
 	"time"
@@ -102,7 +103,7 @@ func TestCacheDir_FallbackHome(t *testing.T) {
 }
 
 // TestCacheDir_WhitespaceXDG covers the branch where XDG_CACHE_HOME contains
-// only whitespace, which stringsTrim reduces to "" so the fallback is used.
+// only whitespace, which strings.TrimSpace reduces to "" so the fallback is used.
 func TestCacheDir_WhitespaceXDG(t *testing.T) {
 	t.Setenv("XDG_CACHE_HOME", "  \t\n ")
 	got, err := CacheDir()
@@ -140,7 +141,7 @@ func TestSetWindow_ClampHigh(t *testing.T) {
 // has no leading or trailing whitespace, so the original string is returned.
 func TestStringsTrim_NoTrimNeeded(t *testing.T) {
 	in := "hello"
-	got := stringsTrim(in)
+	got := strings.TrimSpace(in)
 	if got != "hello" {
 		t.Fatalf("expected %q, got %q", "hello", got)
 	}
@@ -148,7 +149,7 @@ func TestStringsTrim_NoTrimNeeded(t *testing.T) {
 
 // TestStringsTrim_AllWhitespace covers trimming a string that is entirely whitespace.
 func TestStringsTrim_AllWhitespace(t *testing.T) {
-	got := stringsTrim("  \t\r\n  ")
+	got := strings.TrimSpace("  \t\r\n  ")
 	if got != "" {
 		t.Fatalf("expected empty, got %q", got)
 	}
@@ -156,7 +157,7 @@ func TestStringsTrim_AllWhitespace(t *testing.T) {
 
 // TestStringsTrim_LeadingAndTrailing covers trimming from both ends.
 func TestStringsTrim_LeadingAndTrailing(t *testing.T) {
-	got := stringsTrim("  abc  ")
+	got := strings.TrimSpace("  abc  ")
 	if got != "abc" {
 		t.Fatalf("expected %q, got %q", "abc", got)
 	}
@@ -164,7 +165,7 @@ func TestStringsTrim_LeadingAndTrailing(t *testing.T) {
 
 // TestStringsTrim_Empty covers the empty string edge case.
 func TestStringsTrim_Empty(t *testing.T) {
-	got := stringsTrim("")
+	got := strings.TrimSpace("")
 	if got != "" {
 		t.Fatalf("expected empty, got %q", got)
 	}
diff --git a/internal/tmux/status.go b/internal/tmux/status.go
index dcc0714..2f8cff6 100644
--- a/internal/tmux/status.go
+++ b/internal/tmux/status.go
@@ -76,7 +76,7 @@ func FormatGlobalStatusColored(globalReqs int64, globalRPM float64, globalIn, gl
 	gout := textutil.HumanBytes(globalOut)
 	head := fmt.Sprintf("%sΣ@%s %s↑%s%s %s↓%s%s %.1frpm", baseFGToken, humanWindow(window), arrowUpToken, baseFGToken, gin, arrowDownToken, baseFGToken, gout, globalRPM)
 	// Narrow modes: only show Σ head
-	if narrowEnabled() || stringsTrim(scopeProvider) == "" || stringsTrim(scopeModel) == "" {
+	if narrowEnabled() || strings.TrimSpace(scopeProvider) == "" || strings.TrimSpace(scopeModel) == "" {
 		return head
 	}
 	tail := fmt.Sprintf(" | %s:%s %.1frpm %dr", scopeProvider, scopeModel, scopeRPM, scopeReqs)
@@ -108,7 +108,7 @@ func humanWindow(d time.Duration) string {
 
 // narrowEnabled returns true when HEXAI_TMUX_STATUS_NARROW is truthy (1/true/yes/on).
 func narrowEnabled() bool {
-	v := strings.ToLower(stringsTrim(os.Getenv("HEXAI_TMUX_STATUS_NARROW")))
+	v := strings.ToLower(strings.TrimSpace(os.Getenv("HEXAI_TMUX_STATUS_NARROW")))
 	if v == "" {
 		return false
 	}
@@ -122,7 +122,7 @@ func narrowEnabled() bool {
 
 // maxStatusLen returns HEXAI_TMUX_STATUS_MAXLEN parsed as int; 0 disables.
 func maxStatusLen() int {
-	v := stringsTrim(os.Getenv("HEXAI_TMUX_STATUS_MAXLEN"))
+	v := strings.TrimSpace(os.Getenv("HEXAI_TMUX_STATUS_MAXLEN"))
 	if v == "" {
 		return 0
 	}
@@ -146,21 +146,6 @@ func truncateStatus(s string, n int) string {
 	return s[:n-1] + "…"
 }
 
-func stringsTrim(s string) string {
-	i := 0
-	j := len(s)
-	for i < j && (s[i] == ' ' || s[i] == '\t' || s[i] == '\n' || s[i] == '\r') {
-		i++
-	}
-	for j > i && (s[j-1] == ' ' || s[j-1] == '\t' || s[j-1] == '\n' || s[j-1] == '\r') {
-		j--
-	}
-	if i == 0 && j == len(s) {
-		return s
-	}
-	return s[i:j]
-}
-
 // FormatLLMStartStatus renders a short colored heartbeat at start/initialize time.
 // Example: "LLM:openai:gpt-4.1 ⏳"
 func FormatLLMStartStatus(provider, model string) string {
diff --git a/internal/tmux/status_coverage_test.go b/internal/tmux/status_coverage_test.go
index 8f7c034..0c76ee6 100644
--- a/internal/tmux/status_coverage_test.go
+++ b/internal/tmux/status_coverage_test.go
@@ -141,7 +141,7 @@ func TestTruncateStatus(t *testing.T) {
 	}
 }
 
-// --- stringsTrim ---
+// --- strings.TrimSpace ---
 
 func TestStringsTrim(t *testing.T) {
 	tests := []struct {
@@ -163,9 +163,9 @@ func TestStringsTrim(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got := stringsTrim(tt.s)
+			got := strings.TrimSpace(tt.s)
 			if got != tt.want {
-				t.Errorf("stringsTrim(%q) = %q, want %q", tt.s, got, tt.want)
+				t.Errorf("strings.TrimSpace(%q) = %q, want %q", tt.s, got, tt.want)
 			}
 		})
 	}