enumer/enumer.go

156 lines
3.9 KiB
Go

package main
import "fmt"
// Arguments to format are:
// [1]: type name
const stringNameToValueMethod = `// %[1]sString returns a %[1]s for s.
// It returns an error if s is not a %[1]s.
func %[1]sString(s string) (%[1]s, error) {
if val, ok := _%[1]sNameToValueMap[s]; ok {
return val, nil
}
return 0, fmt.Errorf("%%s does not belong to %[1]s values", s)
}
`
// Arguments to format are:
// [1]: type name
const stringValuesMethod = `// %[1]sValues returns all values of the enum.
func %[1]sValues() []%[1]s {
return _%[1]sValues
}
`
// Arguments to format are:
// [1]: type name
const stringBelongsMethodLoop = `// IsA%[1]s reports whether the value is a member of the enum.
func (i %[1]s) IsA%[1]s() bool {
for _, v := range _%[1]sValues {
if i == v {
return true
}
}
return false
}
`
// Arguments to format are:
// [1]: type name
const stringBelongsMethodSet = `// IsA%[1]s reports whether the value is a member of the enum.
func (i %[1]s) IsA%[1]s() bool {
_, ok := _%[1]sMap[i]
return ok
}
`
func (g *Generator) buildBasicExtras(runs [][]Value, typeName string, runsThreshold int) {
// At this moment, either "g.declareIndexAndNameVars()" or "g.declareNameVars()" has been called
// Print the slice of values
g.Printf("\nvar _%sValues = []%s{", typeName, typeName)
for _, values := range runs {
for _, value := range values {
g.Printf("\t%s, ", value.str)
}
}
g.Printf("}\n\n")
// Print the map between name and value
g.Printf("\nvar _%sNameToValueMap = map[string]%s{\n", typeName, typeName)
thereAreRuns := len(runs) > 1 && len(runs) <= runsThreshold
var n int
var runID string
for i, values := range runs {
if thereAreRuns {
runID = "_" + fmt.Sprintf("%d", i)
n = 0
} else {
runID = ""
}
for _, value := range values {
g.Printf("\t_%sName%s[%d:%d]: %s,\n", typeName, runID, n, n+len(value.name), &value)
n += len(value.name)
}
}
g.Printf("}\n\n")
// Print the basic extra methods
g.Printf(stringNameToValueMethod, typeName)
g.Printf(stringValuesMethod, typeName)
if len(runs) < runsThreshold {
g.Printf(stringBelongsMethodLoop, typeName)
} else { // There is a map of values, the code is simpler then
g.Printf(stringBelongsMethodSet, typeName)
}
}
// Arguments to format are:
// [1]: type name
const jsonMethods = `// MarshalJSON implements the json.Marshaler interface.
func (i %[1]s) MarshalJSON() ([]byte, error) {
return json.Marshal(i.String())
}
// UnmarshalJSON implements the json.Unmarshaler interface.
func (i *%[1]s) UnmarshalJSON(data []byte) error {
var s string
if err := json.Unmarshal(data, &s); err != nil {
return fmt.Errorf("%[1]s should be a string, got %%s", data)
}
var err error
*i, err = %[1]sString(s)
return err
}
`
func (g *Generator) buildJSONMethods(runs [][]Value, typeName string, runsThreshold int) {
g.Printf(jsonMethods, typeName)
}
// Arguments to format are:
// [1]: type name
const textMethods = `
// MarshalText implements the encoding.TextMarshaler interface.
func (i %[1]s) MarshalText() ([]byte, error) {
return []byte(i.String()), nil
}
// UnmarshalText implements the encoding.TextUnmarshaler interface.
func (i *%[1]s) UnmarshalText(text []byte) error {
var err error
*i, err = %[1]sString(string(text))
return err
}
`
func (g *Generator) buildTextMethods(runs [][]Value, typeName string, runsThreshold int) {
g.Printf(textMethods, typeName)
}
// Arguments to format are:
// [1]: type name
const yamlMethods = `// MarshalYAML implements the yaml.Marshaler interface.
func (i %[1]s) MarshalYAML() (interface{}, error) {
return i.String(), nil
}
// UnmarshalYAML implements the yaml.Unmarshaler interface.
func (i *%[1]s) UnmarshalYAML(unmarshal func(interface{}) error) error {
var s string
if err := unmarshal(&s); err != nil {
return err
}
var err error
*i, err = %[1]sString(s)
return err
}
`
func (g *Generator) buildYAMLMethods(runs [][]Value, typeName string, runsThreshold int) {
g.Printf(yamlMethods, typeName)
}