chore: add testify and improve test

go.mod

@@ -2,4 +2,13 @@ module gitlab.nexdev.uk/pub/go-slog
 
 go 1.20
 
-require golang.org/x/exp v0.0.0-20230711023510-fffb14384f22
+require (
+	github.com/stretchr/testify v1.8.4
+	golang.org/x/exp v0.0.0-20230711023510-fffb14384f22
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

+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/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 v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 golang.org/x/exp v0.0.0-20230711023510-fffb14384f22 h1:FqrVOBQxQ8r/UwwXibI0KMolVhvFiGobSfdE33deHJM=
 golang.org/x/exp v0.0.0-20230711023510-fffb14384f22/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

slog_test.go

@@ -4,31 +4,69 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"github.com/stretchr/testify/assert"
 	"golang.org/x/exp/slog"
 	"testing"
+	"time"
 )
 
+type log struct {
+	Date    time.Time   `json:"date"`
+	Status  string      `json:"status"`
+	Message string      `json:"message"`
+	Source  slog.Source `json:"source"`
+}
+
 func TestNew(t *testing.T) {
+	// Arrange
 	var buf bytes.Buffer
 
 	logger := New(WithWriter(&buf))
+
+	// Act
 	logger.Info("Foo", slog.String("bar", "baz"))
 	logger.Error("Bar", slog.String("baz", "qux"))
 
+	// Assert
 	scanner := bufio.NewScanner(&buf)
 
-	// Scan the first log.
-	scanner.Scan()
-	infoLog := scanner.Bytes()
-	var infoLogMap map[string]any
-	if err := json.Unmarshal(infoLog, &infoLogMap); err != nil {
-		t.Errorf("Failed to unmarshal info log: %s", err.Error())
-	}
-	t.Log(infoLogMap)
-	if infoLogMap["status"] != "info" {
-		t.Errorf("Expected info log level, got %s", infoLogMap["level"])
+	// Scan the first log
+	assert.True(t, scanner.Scan())
+	var (
+		rawInfoLog = scanner.Bytes()
+		infoLog    = struct {
+			log
+			Bar string `json:"bar"`
+		}{}
+	)
+	if err := json.Unmarshal(rawInfoLog, &infoLog); err != nil {
+		t.Errorf("Failed to unmarshal info log: %s", err)
 	}
-	if infoLogMap["bar"] != "baz" {
-		t.Errorf("Expected bar=baz, got %s", infoLogMap["bar"])
+
+	assert.Equal(t, "info", infoLog.Status)
+	assert.Equal(t, "Foo", infoLog.Message)
+	assert.Equal(t, "baz", infoLog.Bar)
+	assert.WithinDuration(t, time.Now(), infoLog.Date, 1*time.Second)
+
+	// Scan the second log
+	assert.True(t, scanner.Scan())
+	var (
+		rawErrorLog = scanner.Bytes()
+		errorLog    = struct {
+			log
+			Baz string `json:"baz"`
+		}{}
+	)
+	if err := json.Unmarshal(rawErrorLog, &errorLog); err != nil {
+		t.Errorf("Failed to unmarshal error log: %s", err)
 	}
+
+	assert.Equal(t, "error", errorLog.Status)
+	assert.Equal(t, "Bar", errorLog.Message)
+	assert.Equal(t, "qux", errorLog.Baz)
+	assert.WithinDuration(t, time.Now(), errorLog.Date, 1*time.Second)
+
+	// Assert that there are no more logs
+	assert.False(t, scanner.Scan())
+	assert.NoError(t, scanner.Err())
 }