如何隔离凉亭中的依赖关系

Question

I recall reading somewhere that in bower you can install packages as subtrees, meaning that one project can use multiple versions of the same library.. with each version of the library acting as a dependency for other libraries that need the different versions.

as an example.. suppose I'm working on a project which uses both angular-google-maps and ui-slider .. angular-google-maps requires at least angular 1.2.18+ and ui-slider needs angular 1.0.8 ` I was hoping to get something like this (ie output of bower list):

├── angular#1.2.18
├─┬ angular-google-maps#1.1.2 extraneous (latest is 1.1.6)
│ ├── angular#1.2.18
│ └── ..
├─┬ angular-ui-slider#0.0.2
│ ├── angular#1.0.8
│ ├── ..

instead what happens is that when i attempt to install ui-slider on my existent project that already uses angular 1.2.18 , I get this prompt:

Unable to find a suitable version for angular, please choose one:
    1) angular#~1.0.x which resolved to 1.0.8 and is required by angular-ui-slider#0.0.2 
    2) angular#1.2.5 which resolved to 1.2.5 and is required by angular-sanitize#1.2.5 
    3) angular#1.2.18 which resolved to 1.2.18 and is required by angular-brunch-seed 
    4) angular#>=1 which resolved to 1.2.19 and is required by angular-bootstrap#0.5.0 
    5) angular#~1.2.0 which resolved to 1.2.19 and is required by angular-masonry#0.8.1 
    6) angular#1.2.x which resolved to 1.2.19 and is required by angular-google-maps#1.1.2 
    7) angular#1.2.19 which resolved to 1.2.19 and is required by angular-animate#1.2.19 
    8) angular#* which resolved to 1.2.19 and is required by restangular#1.4.0

Prefix the choice with ! to persist it to bower.json

I naturally choose one to get 1.0.8:

[?] Answer: 1
bower angular#~1.0.x                    install angular#1.0.8
bower angular-ui-slider#~0.0.2          install angular-ui-slider#0.0.2

However when I run bower list I get:

├── angular#1.0.8 incompatible with 1.2.18 (1.2.18 available, latest is 1.3.0-build.2867+sha.f07af61)
├─┬ angular-animate#1.2.19 (latest is 1.3.0-build.2867+sha.f07af61)
│ └── angular#1.0.8 incompatible with 1.2.19 (1.2.19 available, latest is 1.3.0-build.2867+sha.f07af61)
├─┬ angular-bootstrap#0.5.0 (latest is 0.11.0)
│ └── angular#1.0.8 (1.3.0-build.2867+sha.f07af61 available)
├─┬ angular-cookies#1.2.5 (latest is 1.3.0-build.2867+sha.f07af61)
│ └── angular#1.0.8 incompatible with 1.2.5 (1.2.5 available, latest is 1.3.0-build.2867+sha.f07af61)
├─┬ angular-google-maps#1.1.2 extraneous (latest is 1.1.6)
│ ├── angular#1.0.8 incompatible with 1.2.x (1.2.19 available, latest is 1.3.0-
├─┬ angular-ui-slider#0.0.2
│ ├── angular#1.0.8 (latest is 1.3.0-build.2867+sha.f07af61)
..

question: why did bower make angular 1.0.8 the default angular and the one used for all my other libraries.. rather than keep angular 1.2.18 and just use angular 1.0.8 for angular-ui-slider ?

Answer 1

You can't have two versions of angular running at the same time. So bower asks you to choose the one you want to install. Here you choose 1, so it installs angular 1.0.8 dependency for all your package regardless of the compatibility.
It's a behaviour intended by design.