feat(modules): port shellconfig module to Go

internal/modules/shellconfig/shellconfig_test.go

@@ -0,0 +1,58 @@
+package shellconfig
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/MDietermann/ArduinoArchSetup/internal/config"
+	"github.com/MDietermann/ArduinoArchSetup/internal/module"
+)
+
+type nop struct{}
+
+func (nop) Progress(string, int, int, string) {}
+func (nop) Log(string, string)                {}
+
+func TestShellConfigWritesBlocks(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	m := New(config.ShellConfigSection{
+		Blocks: []config.ShellConfigBlock{
+			{Name: "path", File: ".zshrc", Content: `export PATH="$HOME/.local/bin:$PATH"`},
+		},
+	})
+	st, _ := m.Detect(context.Background())
+	p, _ := m.Plan(context.Background(), st)
+	if err := m.Apply(context.Background(), p, nop{}); err != nil {
+		t.Fatal(err)
+	}
+	data, _ := os.ReadFile(filepath.Join(home, ".zshrc"))
+	if !strings.Contains(string(data), ">>> path >>>") {
+		t.Fatalf("block not present: %q", data)
+	}
+	if !strings.Contains(string(data), `export PATH="$HOME/.local/bin:$PATH"`) {
+		t.Fatalf("content missing: %q", data)
+	}
+}
+
+func TestShellConfigIdempotent(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	cfg := config.ShellConfigSection{Blocks: []config.ShellConfigBlock{
+		{Name: "x", File: ".zshrc", Content: "echo x"},
+	}}
+	m := New(cfg)
+	st, _ := m.Detect(context.Background())
+	p, _ := m.Plan(context.Background(), st)
+	_ = m.Apply(context.Background(), p, nop{})
+	st2, _ := m.Detect(context.Background())
+	p2, _ := m.Plan(context.Background(), st2)
+	if !p2.IsEmpty() {
+		t.Fatalf("second plan not empty: %+v", p2.Actions)
+	}
+}
+
+var _ module.Module = Module{}