Added unit tests in internal/tracegen (#5119)

- Partially fixes #5068

- This commit adds tests for the `Run` function defined in the `internal/tracegen` package.

- make test

- [x] I have read https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [x] I have signed all commits
- [x] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `yarn lint` and `yarn test`

Signed-off-by: VaibhavMalik4187 <[email protected]>

internal/tracegen/config_test.go

@@ -0,0 +1,105 @@
+// Copyright (c) 2024 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package tracegen
+
+import (
+	"errors"
+	"flag"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+	"go.uber.org/zap"
+)
+
+func Test_Run(t *testing.T) {
+	logger := zap.NewNop()
+	tp := sdktrace.NewTracerProvider()
+
+	tests := []struct {
+		name        string
+		config      *Config
+		expectedErr error
+	}{
+		{
+			name:        "Empty config",
+			config:      &Config{},
+			expectedErr: errors.New("either `traces` or `duration` must be greater than 0"),
+		},
+		{
+			name: "Non-empty config",
+			config: &Config{
+				Workers:    2,
+				Traces:     10,
+				ChildSpans: 5,
+				Attributes: 20,
+				AttrKeys:   50,
+				AttrValues: 100,
+			},
+			expectedErr: nil,
+		},
+		{
+			name: "Traces and duration set to 0",
+			config: &Config{
+				Traces:   0,
+				Duration: 0,
+			},
+			expectedErr: errors.New("either `traces` or `duration` must be greater than 0"),
+		},
+		{
+			name: "Negative traces, positive duration",
+			config: &Config{
+				Traces:   -7,
+				Duration: 7,
+			},
+			expectedErr: nil,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tracers := []trace.Tracer{tp.Tracer("Test-Tracer")}
+			err := Run(tt.config, tracers, logger)
+			assert.Equal(t, tt.expectedErr, err)
+		})
+	}
+}
+
+func Test_Flags(t *testing.T) {
+	tests := []struct {
+		name           string
+		fs             *flag.FlagSet
+		config         *Config
+		expectedConfig *Config
+	}{
+		{
+			fs:     &flag.FlagSet{},
+			name:   "Non-empty config",
+			config: &Config{},
+			expectedConfig: &Config{
+				Workers:       1,
+				Traces:        1,
+				ChildSpans:    1,
+				Attributes:    11,
+				AttrKeys:      97,
+				AttrValues:    1000,
+				Debug:         false,
+				Firehose:      false,
+				Pause:         1000,
+				Duration:      0,
+				Service:       "tracegen",
+				Services:      1,
+				TraceExporter: "otlp-http",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tt.config.Flags(tt.fs)
+			assert.Equal(t, tt.expectedConfig, tt.config)
+		})
+	}
+}

internal/tracegen/worker_test.go

@@ -0,0 +1,57 @@
+// Copyright (c) 2024 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package tracegen
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/jaegertracing/jaeger/pkg/testutils"
+	"github.com/stretchr/testify/assert"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+)
+
+func Test_SimulateTraces(t *testing.T) {
+	logger, buf := testutils.NewLogger()
+	tp := sdktrace.NewTracerProvider()
+	tracers := []trace.Tracer{tp.Tracer("stdout")}
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+	var running uint32 = 1
+
+	tests := []struct {
+		name           string
+		worker         *worker
+		expectedOutput string
+	}{
+		{
+			name: "stdout tracer",
+			worker: &worker{
+				logger:  logger,
+				tracers: tracers,
+				wg:      &wg,
+				id:      7,
+				running: &running,
+				Config: Config{
+					Traces:   7,
+					Duration: time.Second,
+					Pause:    time.Second,
+					Service:  "stdout",
+					Debug:    true,
+					Firehose: true,
+				},
+			},
+			expectedOutput: "{\"level\":\"info\",\"msg\":\"Worker 7 generated 7 traces\"}\n",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tt.worker.simulateTraces()
+			assert.Equal(t, tt.expectedOutput, buf.String())
+		})
+	}
+}