go.opentelemetry.io/otel v1.45.0: RecordError records an exception event leaving span status as Unset, while SetStatus Ok irrevocably locks the span status against subsequent Error updates

# Notes

- **search_known_solution result**: The network returned sample `sha256:3f14ed288a161c7b18e8a641230a1acbbe95a6630bf2bfe7bf77cc02b2958d34` ("Unwired OpenTelemetry tracers silently emit invalid zero-context spans while batch-buffered tracers drop spans without explicit flush or shutdown"). We selected a different trap: `Span.RecordError` only records an exception event without setting span status to `codes.Error`, and `Span.SetStatus(codes.Ok)` irrevocably locks span status against subsequent `codes.Error` assignments.
- **What a model would write instead**: A model writes `span.RecordError(err)` expecting it to mark the span status as `codes.Error`, calls `span.RecordError(nil)` expecting error logging, or sets `span.SetStatus(codes.Ok, ...)` before deferred cleanups assuming `span.SetStatus(codes.Error, ...)` can override it on failure.
- **How the wrong version fails**: Fails silently with a green build: the application runs and exports spans without error, but failed spans remain categorized with `codes.Unset` or `codes.Ok` status in trace collectors, hiding errors from dashboards, SLIs, and alert monitors.

{"case":{"caseId":"case:sha256:02fbc4fe34e944c7d402f1b000ff09c86e8c9ea52b21de97e6e0bc3c64f65801","contract":["assert RecordError records exception event with type and message but leaves span status as Unset","assert RecordError with nil error is a no-op recording zero events","assert marking span status as Error requires explicit SetStatus call with description","assert SetStatus Ok is terminal and cannot be overridden by subsequent SetStatus Error","assert SetStatus Ok overrides earlier Error status and clears description","assert SetStatus Unset cannot demote an already set Error or Ok status"],"goal":"RecordError records an exception event leaving span status as Unset, while SetStatus Ok irrevocably locks the span status against subsequent Error updates","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel@v1.45.0","pkg:golang/go.opentelemetry.io/otel/trace@v1.45.0","pkg:golang/go.opentelemetry.io/otel/sdk@v1.45.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/otel/trace.Span.RecordError","go.opentelemetry.io/otel/trace.Span.SetStatus","go.opentelemetry.io/otel/codes.Error","go.opentelemetry.io/otel/codes.Ok","go.opentelemetry.io/otel/codes.Unset","go.opentelemetry.io/otel/sdk/trace.NewTracerProvider"]},"contractCommand":["go","test","./..."],"environment":{"arch":"x64","ecosystem":"golang","executionContext":"go","language":"go","os":"linux","packageManager":"gomod","runtime":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/otel@v1.45.0","pkg:golang/go.opentelemetry.io/otel/trace@v1.45.0","pkg:golang/go.opentelemetry.io/otel/sdk@v1.45.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/otel/trace.Span.RecordError","go.opentelemetry.io/otel/trace.Span.SetStatus","go.opentelemetry.io/otel/codes.Error","go.opentelemetry.io/otel/codes.Ok","go.opentelemetry.io/otel/codes.Unset","go.opentelemetry.io/otel/sdk/trace.NewTracerProvider"],"verifierAdapter":"golang@1"}

module sample

go 1.26.5

require (
	go.opentelemetry.io/otel v1.45.0
	go.opentelemetry.io/otel/sdk v1.45.0
	go.opentelemetry.io/otel/trace v1.45.0
)

require (
	github.com/cespare/xxhash/v2 v2.3.0 // indirect
	github.com/go-logr/logr v1.4.4 // indirect
	github.com/go-logr/stdr v1.2.2 // indirect
	github.com/google/uuid v1.6.0 // indirect
	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
	go.opentelemetry.io/otel/metric v1.45.0 // indirect
	golang.org/x/sys v0.47.0 // indirect
)

github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
github.com/go-logr/logr v1.4.4 h1:tG4xh9yMsRCAiodLVTxyrkzSZ9+o0L1Kg/+cPVcbP/8=
github.com/go-logr/logr v1.4.4/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
go.opentelemetry.io/otel v1.45.0 h1:pdrWmLHofpubmArBv1LgFSv1Z0Ie/ppdZzu+kUN5EeU=
go.opentelemetry.io/otel v1.45.0/go.mod h1:XZxIqPapzEYnhNSScF5DIqXhm/rYi0FzCe2XddAwZfQ=
go.opentelemetry.io/otel/metric v1.45.0 h1:7Eg1uH7CJ5cXv9is6tnBe1FI6rj1nwUdbFypRm3br/M=
go.opentelemetry.io/otel/metric v1.45.0/go.mod h1:HAPbm1nd3p1PmFH7v2dR+6BjXxw+Lq4a2+pndMAm08s=
go.opentelemetry.io/otel/sdk v1.45.0 h1:4VVSMgQ83dUgW2aoX5f6JgLvHwIvzcuLnF9lUdCSpCw=
go.opentelemetry.io/otel/sdk v1.45.0/go.mod h1:Sr40LgXV7DsKMMJMKOhUWOgMWTfAaqvm2kF0g7ilwuA=
go.opentelemetry.io/otel/sdk/metric v1.45.0 h1:oVFszMfyj1Am6s24Vtc7wBb8BKLcwepJjNEYILuiE3o=
go.opentelemetry.io/otel/sdk/metric v1.45.0/go.mod h1:vUWUxDZvu1WVRj8JA8S0AdhsPrZoDpA2DdZauIh4mDA=
go.opentelemetry.io/otel/trace v1.45.0 h1:l/mP6Uv7oNO7/TblbhpbgMidxhq1uO/rPsikOyVhxag=
go.opentelemetry.io/otel/trace v1.45.0/go.mod h1:qoJJA2xNMnxRrdISU/kLtfUH2wNeQbiv+jhs/CxI8bc=
go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
golang.org/x/sys v0.47.0 h1:o7XGOvZQCADBQQ4Y7VNq2dRWQR7JmOUW8Kxx4ZsNgWs=
golang.org/x/sys v0.47.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package sample_test

import (
	"context"
	"errors"
	"testing"

	"go.opentelemetry.io/otel/codes"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	"go.opentelemetry.io/otel/sdk/trace/tracetest"
	"go.opentelemetry.io/otel/trace"
)

func TestSpanRecordErrorAndStatusSemantics(t *testing.T) {
	ctx := context.Background()

	t.Run("RecordError records exception event but leaves span status Unset", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-record-error")
		err := errors.New("database connection refused")
		span.RecordError(err, trace.WithStackTrace(true))
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		s := spans[0]

		// Trap 1: RecordError adds an exception event with exception attributes
		if len(s.Events) != 1 {
			t.Fatalf("expected 1 event, got %d", len(s.Events))
		}
		event := s.Events[0]
		if event.Name != "exception" {
			t.Errorf("expected event name 'exception', got %q", event.Name)
		}

		hasType, hasMsg, hasStack := false, false, false
		for _, attr := range event.Attributes {
			switch string(attr.Key) {
			case "exception.type":
				hasType = true
				if attr.Value.AsString() != "*errors.errorString" {
					t.Errorf("expected exception.type '*errors.errorString', got %q", attr.Value.AsString())
				}
			case "exception.message":
				hasMsg = true
				if attr.Value.AsString() != "database connection refused" {
					t.Errorf("expected exception.message 'database connection refused', got %q", attr.Value.AsString())
				}
			case "exception.stacktrace":
				hasStack = true
			}
		}
		if !hasType || !hasMsg || !hasStack {
			t.Errorf("missing expected exception attributes: type=%v, msg=%v, stack=%v", hasType, hasMsg, hasStack)
		}

		// Trap 2: A naive model expects s.Status.Code == codes.Error.
		// In reality, RecordError leaves status code as codes.Unset (0).
		if s.Status.Code != codes.Unset {
			t.Errorf("expected status code Unset (0), got %v", s.Status.Code)
		}
		if s.Status.Description != "" {
			t.Errorf("expected empty description, got %q", s.Status.Description)
		}
	})

	t.Run("RecordError with nil error is a no-op", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-nil-error")
		span.RecordError(nil)
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		if len(spans[0].Events) != 0 {
			t.Errorf("expected 0 events for nil error, got %d", len(spans[0].Events))
		}
	})

	t.Run("SetStatus Error requires explicit call to mark span failure", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-explicit-error")
		err := errors.New("timeout reading socket")
		span.RecordError(err)
		span.SetStatus(codes.Error, err.Error())
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		s := spans[0]

		if s.Status.Code != codes.Error {
			t.Errorf("expected status Error (1), got %v", s.Status.Code)
		}
		if s.Status.Description != "timeout reading socket" {
			t.Errorf("expected description 'timeout reading socket', got %q", s.Status.Description)
		}
	})

	t.Run("SetStatus Ok is terminal and cannot be overridden by Error", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-ok-precedence")

		// First, mark operation as Ok
		span.SetStatus(codes.Ok, "success info")

		// Later (e.g. in deferred cleanup), attempt to set status to Error
		span.SetStatus(codes.Error, "deferred cleanup failed")
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		s := spans[0]

		// Per OTel spec: Ok takes final precedence over Error.
		// Calling SetStatus(Error) on a span that is already Ok is silently ignored.
		if s.Status.Code != codes.Ok {
			t.Errorf("expected status to remain Ok (2), got %v", s.Status.Code)
		}
		if s.Status.Description != "" {
			t.Errorf("expected empty description for Ok status, got %q", s.Status.Description)
		}
	})

	t.Run("SetStatus Ok overrides previous Error and clears description", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-error-recovered")

		// Initial failure
		span.SetStatus(codes.Error, "transient error")

		// Retried and succeeded -> set to Ok
		span.SetStatus(codes.Ok, "")
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		s := spans[0]

		// Error can be overridden by Ok
		if s.Status.Code != codes.Ok {
			t.Errorf("expected status Ok, got %v", s.Status.Code)
		}
		if s.Status.Description != "" {
			t.Errorf("expected description to be cleared on Ok, got %q", s.Status.Description)
		}
	})

	t.Run("SetStatus Unset cannot demote Error or Ok", func(t *testing.T) {
		exporter := tracetest.NewInMemoryExporter()
		tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exporter))
		tracer := tp.Tracer("test-tracer")

		_, span := tracer.Start(ctx, "op-demote-unset")
		span.SetStatus(codes.Error, "persisted error")
		span.SetStatus(codes.Unset, "reset")
		span.End()

		spans := exporter.GetSpans()
		if len(spans) != 1 {
			t.Fatalf("expected 1 span, got %d", len(spans))
		}
		s := spans[0]

		// Status remains Error
		if s.Status.Code != codes.Error {
			t.Errorf("expected status Error, got %v", s.Status.Code)
		}
		if s.Status.Description != "persisted error" {
			t.Errorf("expected description 'persisted error', got %q", s.Status.Description)
		}
	})
}