why doesn't bower update angular upgrade my angular?

Question

I have angular 1.2.3 and I want to upgrade to 1.2.7

> cat bower.json
...
  "dependencies": {
    "json3": "~3.2.4",
    "jquery": "~1.9.1",
    "es5-shim": "~2.0.8",
    "toastr": "~2.0.1",
    "angular-ui-tinymce": "latest",
    "underscore": "~1.5.2",
    "underscore.string": "~2.3.3",
    "angular-ui-utils": "~0.0.4",
    "angular-dragdrop": "~1.0.5",
    "angular-cookies": "~1.2.3",
    "angular-animate": "~1.2.3",
    "angular-resource": "~1.2.3",
    "angular": "~1.2.3"
  },
  "devDependencies": {
    "angular-mocks": "~1.2.3",
    "bootstrap": "~3.0.1",
    "font-awesome": "~4.0.3",
    "angular-bootstrap-affix": "~0.3.0"
  }
...

I don't know what the following output even means...., what is it doing?

> bower update angular
bower angular#~1.x              cached git://github.com/angular/bower-angular.git#1.2.7
bower angular#~1.x            validate 1.2.7 against git://github.com/angular/bower-angular.git#~1.x
bower angular#>= 1.0.2          cached git://github.com/angular/bower-angular.git#1.2.7
bower angular#>= 1.0.2        validate 1.2.7 against git://github.com/angular/bower-angular.git#>= 1.0.2
bower angular#1.2.3             cached git://github.com/angular/bower-angular.git#1.2.3
bower angular#1.2.3           validate 1.2.3 against git://github.com/angular/bower-angular.git#1.2.3
bower angular#~1.2.3            cached git://github.com/angular/bower-angular.git#1.2.7
bower angular#~1.2.3          validate 1.2.7 against git://github.com/angular/bower-angular.git#~1.2.3
bower angular#~1.x                 new version for git://github.com/angular/bower-angular.git#~1.x
bower angular#~1.x             resolve git://github.com/angular/bower-angular.git#~1.x
bower angular#>= 1.0.2             new version for git://github.com/angular/bower-angular.git#>= 1.0.2
bower angular#>= 1.0.2         resolve git://github.com/angular/bower-angular.git#>= 1.0.2
bower angular#~1.2.3               new version for git://github.com/angular/bower-angular.git#~1.2.3
bower angular#~1.2.3           resolve git://github.com/angular/bower-angular.git#~1.2.3
bower angular#~1.x            download https://github.com/angular/bower-angular/archive/v1.2.8-build.2095+sha.28fc80b.tar.gz
bower angular#>= 1.0.2        download https://github.com/angular/bower-angular/archive/v1.2.8-build.2095+sha.28fc80b.tar.gz
bower angular#~1.2.3          download https://github.com/angular/bower-angular/archive/v1.2.8-build.2095+sha.28fc80b.tar.gz
bower angular#>= 1.0.2         extract archive.tar.gz
bower angular#>= 1.0.2        resolved git://github.com/angular/bower-angular.git#1.2.8-build.2095+sha.28fc80b
bower angular#~1.x             extract archive.tar.gz
bower angular#~1.x            resolved git://github.com/angular/bower-angular.git#1.2.8-build.2095+sha.28fc80b
bower angular#~1.2.3           extract archive.tar.gz
bower angular#~1.2.3          resolved git://github.com/angular/bower-angular.git#1.2.8-build.2095+sha.28fc80b

nothing changed? I'm still on 1.2.3

> git diff
diff --git a/ngapp/app/bower_components/angular/.bower.json b/ngapp/app/bower_components/angular/.bower.json
index dc9d0b6..842a1f3 100644
--- a/ngapp/app/bower_components/angular/.bower.json
+++ b/ngapp/app/bower_components/angular/.bower.json
@@ -11,6 +11,6 @@
     "commit": "b112b099971f4cf016023bdeb00b267e9bf6dfb5"
   },
   "_source": "git://github.com/angular/bower-angular.git",
-  "_target": "~1.2.3",
+  "_target": "1.2.3",
   "_originalSource": "angular"
 }

> bower --version
1.2.8

Am I missing something?

> bower info angular
.... shows all versions including 1.2.7 and 1.2.8-builds as well

Answer 1

I think your dependencies are preventing you from updating angular in isolation. E.g., look at bower_components/angular-route/bower.json. You will see a specific version of angular listed as a dependency ("1.2.3") and not a ~/"reasonably close" specifier" ("~1.2.3"). So you are trying to update just angular, but the farthest that bower can take your angular is the current version since you have other packages that depend on exactly that version.

If you do bower update then bower will have the opportunity to update all your packages, including angular-route and other packages that are holding angular back. The updates to these packages will now allow bower to update angular while satisfying dependencies. Also, I think if you identified all those packages depending on a specific angular version (you can see dependencies with bower list) and passed them as arguments like bower update angular angular-mocks angular-resource angular-route angular-sanitize... then bower could also perform the update.