initial import

core/mapping/fieldoptions.go

@@ -0,0 +1,105 @@
+package mapping
+
+import "fmt"
+
+const notSymbol = '!'
+
+type (
+	// use context and OptionalDep option to determine the value of Optional
+	// nothing to do with context.Context
+	fieldOptionsWithContext struct {
+		FromString bool
+		Optional   bool
+		Options    []string
+		Default    string
+		Range      *numberRange
+	}
+
+	fieldOptions struct {
+		fieldOptionsWithContext
+		OptionalDep string
+	}
+
+	numberRange struct {
+		left         float64
+		leftInclude  bool
+		right        float64
+		rightInclude bool
+	}
+)
+
+func (o *fieldOptionsWithContext) fromString() bool {
+	return o != nil && o.FromString
+}
+
+func (o *fieldOptionsWithContext) getDefault() (string, bool) {
+	if o == nil {
+		return "", false
+	} else {
+		return o.Default, len(o.Default) > 0
+	}
+}
+
+func (o *fieldOptionsWithContext) optional() bool {
+	return o != nil && o.Optional
+}
+
+func (o *fieldOptionsWithContext) options() []string {
+	if o == nil {
+		return nil
+	}
+
+	return o.Options
+}
+
+func (o *fieldOptions) optionalDep() string {
+	if o == nil {
+		return ""
+	} else {
+		return o.OptionalDep
+	}
+}
+
+func (o *fieldOptions) toOptionsWithContext(key string, m Valuer, fullName string) (
+	*fieldOptionsWithContext, error) {
+	var optional bool
+	if o.optional() {
+		dep := o.optionalDep()
+		if len(dep) == 0 {
+			optional = true
+		} else if dep[0] == notSymbol {
+			dep = dep[1:]
+			if len(dep) == 0 {
+				return nil, fmt.Errorf("wrong optional value for %q in %q", key, fullName)
+			}
+
+			_, baseOn := m.Value(dep)
+			_, selfOn := m.Value(key)
+			if baseOn == selfOn {
+				return nil, fmt.Errorf("set value for either %q or %q in %q", dep, key, fullName)
+			} else {
+				optional = baseOn
+			}
+		} else {
+			_, baseOn := m.Value(dep)
+			_, selfOn := m.Value(key)
+			if baseOn != selfOn {
+				return nil, fmt.Errorf("values for %q and %q should be both provided or both not in %q",
+					dep, key, fullName)
+			} else {
+				optional = !baseOn
+			}
+		}
+	}
+
+	if o.fieldOptionsWithContext.Optional == optional {
+		return &o.fieldOptionsWithContext, nil
+	} else {
+		return &fieldOptionsWithContext{
+			FromString: o.FromString,
+			Optional:   optional,
+			Options:    o.Options,
+			Default:    o.Default,
+		}, nil
+	}
+}