charm: allow empty string as default value

charm/config_test.go

 // Copyright 2011, 2012, 2013 Canonical Ltd.
 // Licensed under the AGPLv3, see LICENCE file for details.
 
 package charm_test
 
 import (
         "bytes"
         "fmt"
         . "launchpad.net/gocheck"
         "launchpad.net/juju-core/charm"
 )
 
 type ConfigSuite struct {
         config *charm.Config
 }
 
 var _ = Suite(&ConfigSuite{})
 
 func (s *ConfigSuite) SetUpSuite(c *C) {
         // Just use a single shared config for the whole suite. There's no use case
         // for mutating a config, we we assume that nobody will do so here.
         var err error
         s.config, err = charm.ReadConfig(bytes.NewBuffer([]byte(`
 options:
   title:
     default: My Title
     description: A descriptive title used for the service.
     type: string
+  subtitle:
+    default: ""
+    description: An optional subtitle used for the service.
   outlook:
     description: No default outlook.
     # type defaults to string in python
   username:
     default: admin001
     description: The name of the initial account (given admin permissions).
     type: string
   skill-level:
     description: A number indicating skill.
     type: int
   agility-ratio:
     description: A number from 0 to 1 indicating agility.
     type: float
   reticulate-splines:
     description: Whether to reticulate splines on launch, or not.
     type: boolean
 `)))
         c.Assert(err, IsNil)
 }
 
 func (s *ConfigSuite) TestReadSample(c *C) {
         c.Assert(s.config.Options, DeepEquals, map[string]charm.Option{
                 "title": {
                         Default:     "My Title",
                         Description: "A descriptive title used for the service.",
                         Type:        "string",
                 },
+                "subtitle": {
+                        Default:     "",
+                        Description: "An optional subtitle used for the service.",
+                        Type:        "string",
+                },
                 "username": {
                         Default:     "admin001",
                         Description: "The name of the initial account (given admin permissions).",
                         Type:        "string",
                 },
                 "outlook": {
                         Description: "No default outlook.",
                         Type:        "string",
                 },
                 "skill-level": {
                         Description: "A number indicating skill.",
                         Type:        "int",
                 },
                 "agility-ratio": {
                         Description: "A number from 0 to 1 indicating agility.",
                         Type:        "float",
                 },
                 "reticulate-splines": {
                         Description: "Whether to reticulate splines on launch, or not.",
                         Type:        "boolean",
                 },
         })
 }
 
 func (s *ConfigSuite) TestDefaultSettings(c *C) {
         c.Assert(s.config.DefaultSettings(), DeepEquals, charm.Settings{
                 "title":              "My Title",
+                "subtitle":           "",
                 "username":           "admin001",
                 "outlook":            nil,
                 "skill-level":        nil,
                 "agility-ratio":      nil,
                 "reticulate-splines": nil,
         })
 }
 
 func (s *ConfigSuite) TestFilterSettings(c *C) {
         settings := s.config.FilterSettings(charm.Settings{
                 "title":              "something valid",
+                "subtitle":           "",

[fwereade, 2013/06/28 09:32:11]

Just skip this. You haven't changed the behaviour of FilterSettings, and you're
just duplicating a case that's already tested by "outlook".

[mue, 2013/06/28 13:15:57]

Done.

                 "username":           nil,
                 "unknown":            "whatever",
                 "outlook":            "",
                 "skill-level":        5.5,
                 "agility-ratio":      true,
                 "reticulate-splines": "hullo",
         })
         c.Assert(settings, DeepEquals, charm.Settings{
                 "title":    "something valid",
+                "subtitle": nil,

[dimitern, 2013/06/27 15:01:20]

shouldn't this be "" ?

[fwereade, 2013/06/28 09:32:11]

Nope -- all we've changed is ReadConfig, the usual validation stays the same as
before. Probably not for long, but one bug at a time...

                 "username": nil,
                 "outlook":  nil,
         })
 }
 
 func (s *ConfigSuite) TestValidateSettings(c *C) {
         for i, test := range []struct {
                 info   string
                 input  charm.Settings
                 expect charm.Settings
@@ skipping 256 matching lines @@
 func (s *ConfigSuite) TestDefaultType(c *C) {
         assertDefault := func(type_ string, value string, expected interface{}) {
                 config := fmt.Sprintf(`options: {t: {type: %s, default: %s}}`, type_, value)
                 result, err := charm.ReadConfig(bytes.NewBuffer([]byte(config)))
                 c.Assert(err, IsNil)
                 c.Assert(result.Options["t"].Default, Equals, expected)
         }
 
         assertDefault("boolean", "true", true)
         assertDefault("string", "golden grahams", "golden grahams")
+        assertDefault("string", `""`, "")
         assertDefault("float", "2.2e11", 2.2e11)
         assertDefault("int", "99", int64(99))
 
         assertTypeError := func(type_, str, value string) {
                 config := fmt.Sprintf(`options: {t: {type: %s, default: %s}}`, type_, str)
                 _, err := charm.ReadConfig(bytes.NewBuffer([]byte(config)))
                 expected := fmt.Sprintf(`invalid config default: option "t" expected %s, got %s`, type_, value)
                 c.Assert(err, ErrorMatches, expected)
         }
 
         assertTypeError("boolean", "henry", `"henry"`)
         assertTypeError("string", "2.5", "2.5")
         assertTypeError("float", "123", "123")
         assertTypeError("int", "true", "true")
 }