Revel tool enhancements

* run Command will choose CWD if no additional arguments are supplied
* Added Revel version check, compatible lists are in model/version

model/version.go

@@ -0,0 +1,110 @@
+package model
+
+import (
+	"fmt"
+	"github.com/pkg/errors"
+	"regexp"
+	"strconv"
+)
+
+type Version struct {
+	Prefix      string
+	Major       int
+	Minor       int
+	Maintenance int
+	Suffix      string
+}
+
+// The compatibility list
+var frameworkCompatibleList = [][]string{
+	{"0.0.0", "0.20.0"}, // minimum Revel version to use with this version of the tool
+	{"0.19.99", "0.30.0"},  // Compatible with Framework V 0.19.99 - 0.30.0
+}
+
+// Parses a version like v1.2.3a or 1.2
+var versionRegExp = regexp.MustCompile(`([^\d]*)?([0-9]*)\.([0-9]*)(\.([0-9]*))?(.*)`)
+
+// Parse the version and return it as a Version object
+func ParseVersion(version string) (v *Version, err error) {
+
+	parsedResult := versionRegExp.FindAllStringSubmatch(version, -1)
+	if len(parsedResult) != 1 {
+		err = errors.Errorf("Invalid version %s", version)
+		return
+	}
+	if len(parsedResult[0]) != 7 {
+		err = errors.Errorf("Invalid version %s", version)
+		return
+	}
+	v = &Version{}
+	v.Prefix = parsedResult[0][1]
+	v.Major = v.intOrZero(parsedResult[0][2])
+	v.Minor = v.intOrZero(parsedResult[0][3])
+	v.Maintenance = v.intOrZero(parsedResult[0][5])
+	v.Suffix = parsedResult[0][6]
+
+	return
+}
+
+// Returns 0 or an int value for the string, errors are returned as 0
+func (v *Version) intOrZero(input string) (value int) {
+	if input != "" {
+		value, _ = strconv.Atoi(input)
+	}
+	return value
+}
+
+// Returns true if this major revision is compatible
+func (v *Version) CompatibleFramework(c *CommandConfig) error {
+	for i, rv := range frameworkCompatibleList {
+		start, _ := ParseVersion(rv[0])
+		end, _ := ParseVersion(rv[1])
+		if !v.Newer(start) || v.Newer(end) {
+			continue
+		}
+		// Framework is older then 0.20, turn on historic mode
+		if i == 0 {
+			c.HistoricMode = true
+		}
+		return nil
+	}
+	return errors.New("Unknown versions - do a 'go get -u github.com/revel/cmd/revel github.com/revel/modules github.com/revel/revel'")
+}
+
+// Returns true if this major revision is newer then the passed in
+func (v *Version) MajorNewer(o *Version) bool {
+	if v.Major != o.Major {
+		return v.Major > o.Major
+	}
+	return false
+}
+
+// Returns true if this major or major and minor revision is newer then the value passed in
+func (v *Version) MinorNewer(o *Version) bool {
+	if v.Major != o.Major {
+		return v.Major > o.Major
+	}
+	if v.Minor != o.Minor {
+		return v.Minor > o.Minor
+	}
+	return false
+}
+
+// Returns true if the version is newer then the current on
+func (v *Version) Newer(o *Version) bool {
+	if v.Major != o.Major {
+		return v.Major > o.Major
+	}
+	if v.Minor != o.Minor {
+		return v.Minor > o.Minor
+	}
+	if v.Maintenance != o.Maintenance {
+		return v.Maintenance > o.Maintenance
+	}
+	return false
+}
+
+// Convert the version to a string
+func (v *Version) String() string {
+	return fmt.Sprintf("%s%d.%d.%d%s", v.Prefix, v.Major, v.Minor, v.Maintenance, v.Suffix)
+}