Add Certificates page and Traefik API frontend client

backend/internal/config/file/diff_test.go

@@ -0,0 +1,110 @@
+package file
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestUnifiedDiff_Insertion(t *testing.T) {
+	old := "a\nb\nc"
+	new := "a\nx\nb\nc"
+	diff := UnifiedDiff("app.yml", old, new)
+	if !strings.Contains(diff, "+x") {
+		t.Fatalf("expected insertion of x, got %q", diff)
+	}
+	if !strings.Contains(diff, " a") || !strings.Contains(diff, " b") {
+		t.Fatalf("expected context lines, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_Deletion(t *testing.T) {
+	old := "a\nb\nc\nd"
+	new := "a\nc\nd"
+	diff := UnifiedDiff("app.yml", old, new)
+	if !strings.Contains(diff, "-b") {
+		t.Fatalf("expected deletion of b, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_Replacement(t *testing.T) {
+	old := "http:\n  routers:\n    r1:\n      rule: \"Host(`a.com`)\"\n      service: s1"
+	new := "http:\n  routers:\n    r1:\n      rule: \"Host(`b.com`)\"\n      service: s1"
+	diff := UnifiedDiff("app.yml", old, new)
+	if !strings.Contains(diff, "-") || !strings.Contains(diff, "+") {
+		t.Fatalf("expected replacement diff, got %q", diff)
+	}
+	if !strings.Contains(diff, "a.com") || !strings.Contains(diff, "b.com") {
+		t.Fatalf("expected both old and new rule in diff, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_MovedBlock(t *testing.T) {
+	old := "line1\nline2\nline3\nline4\nline5"
+	new := "line1\nline4\nline5\nline2\nline3"
+	diff := UnifiedDiff("app.yml", old, new)
+	// moved block should appear as deletion and insertion (difflib shows moved 4/5)
+	if !strings.Contains(diff, "-line4") || !strings.Contains(diff, "-line5") {
+		t.Fatalf("expected moved lines as deletion (4/5), got %q", diff)
+	}
+	if !strings.Contains(diff, "+line4") || !strings.Contains(diff, "+line5") {
+		t.Fatalf("expected moved lines as insertion (4/5), got %q", diff)
+	}
+	// also ensure diff is not empty and contains context
+	if !strings.Contains(diff, "line1") {
+		t.Fatalf("expected context line1, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_EmptyFiles(t *testing.T) {
+	diff := UnifiedDiff("app.yml", "", "")
+	if diff != "" {
+		t.Fatalf("empty both should be empty diff, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_NewFile(t *testing.T) {
+	old := ""
+	new := "http:\n  routers:\n    r:\n      rule: \"Host(`x.com`)\""
+	diff := UnifiedDiff("new.yml", old, new)
+	if !strings.Contains(diff, "+http:") {
+		t.Fatalf("new file should show additions, got %q", diff)
+	}
+	if !strings.Contains(diff, "--- a/new.yml") || !strings.Contains(diff, "+++ b/new.yml") {
+		t.Fatalf("missing header, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_DeletedFile(t *testing.T) {
+	old := "http:\n  routers:\n    r:\n      rule: \"Host(`x.com`)\""
+	new := ""
+	diff := UnifiedDiff("old.yml", old, new)
+	if !strings.Contains(diff, "-http:") {
+		t.Fatalf("deleted file should show deletions, got %q", diff)
+	}
+}
+
+func TestUnifiedDiff_RollbackDiff(t *testing.T) {
+	v1 := "http:\n  routers:\n    r1:\n      rule: \"Host(`a.com`)\"\n      service: s1"
+	v2 := "http:\n  routers:\n    r1:\n      rule: \"Host(`b.com`)\"\n      service: s1"
+	// Simulate apply v1 -> v2, then rollback v2 -> v1 diff should be reverse
+	diffForward := UnifiedDiff("app.yml", v1, v2)
+	diffRollback := UnifiedDiff("app.yml", v2, v1)
+	if diffForward == "" || diffRollback == "" {
+		t.Fatalf("both diffs should be non-empty")
+	}
+	if !strings.Contains(diffForward, "-") || !strings.Contains(diffRollback, "-") {
+		t.Fatalf("expected diffs to contain changes")
+	}
+	// Rollback diff should contain inverse
+	if !strings.Contains(diffRollback, "a.com") || !strings.Contains(diffRollback, "b.com") {
+		t.Fatalf("rollback diff missing expected, got %q", diffRollback)
+	}
+}
+
+func TestUnifiedDiff_Identical(t *testing.T) {
+	content := "http:\n  routers:\n    r: {rule: \"Host(`a.com`)\", service: s}"
+	diff := UnifiedDiff("app.yml", content, content)
+	if diff != "" {
+		t.Fatalf("identical should be empty, got %q", diff)
+	}
+}