log: Change EnabledParameters to have a field instead of getter and setter (#6009)

Allow users to to write less verbose code by changing methods to field.

log/DESIGN.md

@@ -264,9 +264,9 @@ allocations and make it possible to handle new arguments, `Enabled` accepts
 a `EnabledParameters` struct, defined in [logger.go](logger.go), as the second
 method argument.
 
-The `EnabledParameters` getters are returning values using the `(value, ok)`
-idiom in order to indicate if the values were actually set by the caller or if
-there are unspecified.
+The `EnabledParameters` uses fields, instead of getters and setters, to allow
+simpler usage which allows configuring the `EnabledParameters` in the same line
+where `Enabled` is called.
 
 ### noop package
 

log/logger.go

@@ -138,18 +138,5 @@ func WithSchemaURL(schemaURL string) LoggerOption {
 
 // EnabledParameters represents payload for [Logger]'s Enabled method.
 type EnabledParameters struct {
-	severity    Severity
-	severitySet bool
-}
-
-// Severity returns the [Severity] level value, or [SeverityUndefined] if no value was set.
-// The ok result indicates whether the value was set.
-func (r *EnabledParameters) Severity() (value Severity, ok bool) {
-	return r.severity, r.severitySet
-}
-
-// SetSeverity sets the [Severity] level.
-func (r *EnabledParameters) SetSeverity(level Severity) {
-	r.severity = level
-	r.severitySet = true
+	Severity Severity
 }

log/logtest/recorder_test.go

@@ -68,21 +68,16 @@ func TestRecorderLoggerCreatesNewStruct(t *testing.T) {
 
 func TestLoggerEnabled(t *testing.T) {
 	for _, tt := range []struct {
-		name                   string
-		options                []Option
-		ctx                    context.Context
-		buildEnabledParameters func() log.EnabledParameters
-
-		isEnabled bool
+		name          string
+		options       []Option
+		ctx           context.Context
+		enabledParams log.EnabledParameters
+		want          bool
 	}{
 		{
 			name: "the default option enables every log entry",
 			ctx:  context.Background(),
-			buildEnabledParameters: func() log.EnabledParameters {
-				return log.EnabledParameters{}
-			},
-
-			isEnabled: true,
+			want: true,
 		},
 		{
 			name: "with everything disabled",
@@ -91,17 +86,13 @@ func TestLoggerEnabled(t *testing.T) {
 					return false
 				}),
 			},
-			ctx: context.Background(),
-			buildEnabledParameters: func() log.EnabledParameters {
-				return log.EnabledParameters{}
-			},
-
-			isEnabled: false,
+			ctx:  context.Background(),
+			want: false,
 		},
 	} {
 		t.Run(tt.name, func(t *testing.T) {
-			e := NewRecorder(tt.options...).Logger("test").Enabled(tt.ctx, tt.buildEnabledParameters())
-			assert.Equal(t, tt.isEnabled, e)
+			e := NewRecorder(tt.options...).Logger("test").Enabled(tt.ctx, tt.enabledParams)
+			assert.Equal(t, tt.want, e)
 		})
 	}
 }