Merge pull request #36 from b-per/field-as-int

Allow setting struct fields as int

Author: alexflint

README.md

@@ -118,6 +118,19 @@ func main() {
 }
 ```
 
+### Ints
+
+It is also possible to set struct fields as `int` to get the string automatically converted.
+
+```go
+// Matches "12 wombats", "1 wombat" and store the number as int
+type Wisdom struct {
+	Number   int       `^\d+`
+	_   	 string    `\s+`
+	Animal   string    `\w+`
+}
+```
+
 ### Optional fields
 
 When nesting one struct within another, you can make the nested struct optional by marking it with `?`. The following example parses floating point numbers with optional sign and exponent:

builder.go

@@ -16,6 +16,7 @@ const (
 	PosRole
 	SubstructRole
 	StringScalarRole
+	IntScalarRole
 	ByteSliceScalarRole
 	SubmatchScalarRole
 )
@@ -106,6 +107,8 @@ func (b *builder) terminal(f reflect.StructField, fullName string) (*Field, *syn
 		role = EmptyRole
 	case stringType:
 		role = StringScalarRole
+	case intType:
+		role = IntScalarRole
 	case byteSliceType:
 		role = ByteSliceScalarRole
 	case submatchType:

inflate.go

@@ -3,18 +3,21 @@ package restructure
 import (
 	"fmt"
 	"reflect"
+	"strconv"
 )
 
 var (
 	posType = reflect.TypeOf(Pos(0))
 
 	emptyType     = reflect.TypeOf(struct{}{})
 	stringType    = reflect.TypeOf("")
+	intType       = reflect.TypeOf(1)
 	byteSliceType = reflect.TypeOf([]byte{})
 	submatchType  = reflect.TypeOf(Submatch{})
 	scalarTypes   = []reflect.Type{
 		emptyType,
 		stringType,
+		intType,
 		byteSliceType,
 		submatchType,
 	}
@@ -77,6 +80,13 @@ func inflateScalar(dest reflect.Value, match *match, captureIndex int, role Role
 	case StringScalarRole:
 		dest.SetString(string(buf))
 		return nil
+	case IntScalarRole:
+		if intVal, err := strconv.Atoi(string(buf)); err != nil {
+			return fmt.Errorf("unable to capture into %s", dest.Type().String())
+		} else {
+			dest.SetInt(int64(intVal))
+			return nil
+		}
 	case ByteSliceScalarRole:
 		dest.SetBytes(buf)
 		return nil
@@ -128,7 +138,7 @@ func inflateStruct(dest reflect.Value, match *match, structure *Struct) error {
 			if err := inflatePos(val, match, field.capture); err != nil {
 				return err
 			}
-		case StringScalarRole, ByteSliceScalarRole, SubmatchScalarRole:
+		case StringScalarRole, ByteSliceScalarRole, SubmatchScalarRole, IntScalarRole:
 			val := dest.FieldByIndex(field.index)
 			if err := inflateScalar(val, match, field.capture, field.role); err != nil {
 				return err

restructure_test.go

@@ -308,3 +308,19 @@ func TestFindAllWords_Regions(t *testing.T) {
 	assertRegion(t, "is", 4, 6, words[1].S)
 	assertRegion(t, "spam", 7, 11, words[2].S)
 }
+
+type ExprWithInt struct {
+	Number int    `regexp:"^\\d+"`
+	_      string `regexp:"\\s+"`
+	Animal string `regexp:"\\w+$"`
+}
+
+func TestMatchWithInt(t *testing.T) {
+	pattern, err := Compile(ExprWithInt{}, Options{})
+	require.NoError(t, err)
+
+	var v ExprWithInt
+	assert.True(t, pattern.Find(&v, "4 wombats"))
+	assert.Equal(t, 4, v.Number)
+	assert.Equal(t, "wombats", v.Animal)
+}