Implement Cobra CLI tooling, Viper config tooling (#336)

* start pulling out + replacing urfave and config

* replace many many instances of config

* move more stuff => viper

* properly remove urfave

* move some flags to root command

* add testrig commands to root

* alias config file keys

* start adding cli parsing tests

* reorder viper init

* remove config path alias

* fmt

* change config file keys to non-nested

* we're more or less in business now

* tidy up the common func

* go fmt

* get tests passing again

* add note about the cliparsing tests

* reorganize

* update docs with changes

* structure cmd dir better

* rename + move some files around

* fix dangling comma

vendor/github.com/pelletier/go-toml/tomltree_create.go

@@ -0,0 +1,155 @@
+package toml
+
+import (
+	"fmt"
+	"reflect"
+	"time"
+)
+
+var kindToType = [reflect.String + 1]reflect.Type{
+	reflect.Bool:    reflect.TypeOf(true),
+	reflect.String:  reflect.TypeOf(""),
+	reflect.Float32: reflect.TypeOf(float64(1)),
+	reflect.Float64: reflect.TypeOf(float64(1)),
+	reflect.Int:     reflect.TypeOf(int64(1)),
+	reflect.Int8:    reflect.TypeOf(int64(1)),
+	reflect.Int16:   reflect.TypeOf(int64(1)),
+	reflect.Int32:   reflect.TypeOf(int64(1)),
+	reflect.Int64:   reflect.TypeOf(int64(1)),
+	reflect.Uint:    reflect.TypeOf(uint64(1)),
+	reflect.Uint8:   reflect.TypeOf(uint64(1)),
+	reflect.Uint16:  reflect.TypeOf(uint64(1)),
+	reflect.Uint32:  reflect.TypeOf(uint64(1)),
+	reflect.Uint64:  reflect.TypeOf(uint64(1)),
+}
+
+// typeFor returns a reflect.Type for a reflect.Kind, or nil if none is found.
+// supported values:
+// string, bool, int64, uint64, float64, time.Time, int, int8, int16, int32, uint, uint8, uint16, uint32, float32
+func typeFor(k reflect.Kind) reflect.Type {
+	if k > 0 && int(k) < len(kindToType) {
+		return kindToType[k]
+	}
+	return nil
+}
+
+func simpleValueCoercion(object interface{}) (interface{}, error) {
+	switch original := object.(type) {
+	case string, bool, int64, uint64, float64, time.Time:
+		return original, nil
+	case int:
+		return int64(original), nil
+	case int8:
+		return int64(original), nil
+	case int16:
+		return int64(original), nil
+	case int32:
+		return int64(original), nil
+	case uint:
+		return uint64(original), nil
+	case uint8:
+		return uint64(original), nil
+	case uint16:
+		return uint64(original), nil
+	case uint32:
+		return uint64(original), nil
+	case float32:
+		return float64(original), nil
+	case fmt.Stringer:
+		return original.String(), nil
+	case []interface{}:
+		value := reflect.ValueOf(original)
+		length := value.Len()
+		arrayValue := reflect.MakeSlice(value.Type(), 0, length)
+		for i := 0; i < length; i++ {
+			val := value.Index(i).Interface()
+			simpleValue, err := simpleValueCoercion(val)
+			if err != nil {
+				return nil, err
+			}
+			arrayValue = reflect.Append(arrayValue, reflect.ValueOf(simpleValue))
+		}
+		return arrayValue.Interface(), nil
+	default:
+		return nil, fmt.Errorf("cannot convert type %T to Tree", object)
+	}
+}
+
+func sliceToTree(object interface{}) (interface{}, error) {
+	// arrays are a bit tricky, since they can represent either a
+	// collection of simple values, which is represented by one
+	// *tomlValue, or an array of tables, which is represented by an
+	// array of *Tree.
+
+	// holding the assumption that this function is called from toTree only when value.Kind() is Array or Slice
+	value := reflect.ValueOf(object)
+	insideType := value.Type().Elem()
+	length := value.Len()
+	if length > 0 {
+		insideType = reflect.ValueOf(value.Index(0).Interface()).Type()
+	}
+	if insideType.Kind() == reflect.Map {
+		// this is considered as an array of tables
+		tablesArray := make([]*Tree, 0, length)
+		for i := 0; i < length; i++ {
+			table := value.Index(i)
+			tree, err := toTree(table.Interface())
+			if err != nil {
+				return nil, err
+			}
+			tablesArray = append(tablesArray, tree.(*Tree))
+		}
+		return tablesArray, nil
+	}
+
+	sliceType := typeFor(insideType.Kind())
+	if sliceType == nil {
+		sliceType = insideType
+	}
+
+	arrayValue := reflect.MakeSlice(reflect.SliceOf(sliceType), 0, length)
+
+	for i := 0; i < length; i++ {
+		val := value.Index(i).Interface()
+		simpleValue, err := simpleValueCoercion(val)
+		if err != nil {
+			return nil, err
+		}
+		arrayValue = reflect.Append(arrayValue, reflect.ValueOf(simpleValue))
+	}
+	return &tomlValue{value: arrayValue.Interface(), position: Position{}}, nil
+}
+
+func toTree(object interface{}) (interface{}, error) {
+	value := reflect.ValueOf(object)
+
+	if value.Kind() == reflect.Map {
+		values := map[string]interface{}{}
+		keys := value.MapKeys()
+		for _, key := range keys {
+			if key.Kind() != reflect.String {
+				if _, ok := key.Interface().(string); !ok {
+					return nil, fmt.Errorf("map key needs to be a string, not %T (%v)", key.Interface(), key.Kind())
+				}
+			}
+
+			v := value.MapIndex(key)
+			newValue, err := toTree(v.Interface())
+			if err != nil {
+				return nil, err
+			}
+			values[key.String()] = newValue
+		}
+		return &Tree{values: values, position: Position{}}, nil
+	}
+
+	if value.Kind() == reflect.Array || value.Kind() == reflect.Slice {
+		return sliceToTree(object)
+	}
+
+	simpleValue, err := simpleValueCoercion(object)
+	if err != nil {
+		return nil, err
+	}
+	return &tomlValue{value: simpleValue, position: Position{}}, nil
+}