Support flags in arch-hs-diff about arch-hs

[felixonmars]

There seems to be some edge cases in combination of flags & conditional dependencies:

$ arch-hs-diff -f HTTP:warp-tests:true HTTP 4000.3.14 4000.3.15
  ⓘ You assigned flags:
HTTP
    ⚐ warp-tests : True

...
Depends:
    base  >=4.3.0.0 && <4.14
    time  >=1.1.2.3 && <1.10
    array  >=0.3.0.2 && <0.6
    bytestring  >=0.9.1.5 && <0.11
    parsec  >=2.0 && <3.2
--------------------------------------
    base  >=4.3.0.0 && <4.15
    time  >=1.1.2.3 && <1.11
    array  >=0.3.0.2 && <0.6
    bytestring  >=0.9.1.5 && <0.11
    parsec  >=2.0 && <3.2
MakeDepends:
    case-insensitive  >=0.4.0.1 && <1.3
    deepseq  >=1.3.0.0 && <1.5
    HUnit  >=1.2.0.1 && <1.7
    httpd-shed  >=0.4 && <0.5
    http-types  >=0.8.0 && <1.0
    mtl  >=1.1.1.0 && <2.3
    pureMD5  >=0.2.4 && <2.2
    split  >=0.1.3 && <0.3
    test-framework  >=0.2.0 && <0.9
    test-framework-hunit  >=0.3.0 && <0.4
    wai  >=2.1.0 && <3.3
    warp  >=2.1.0 && <3.3

The .cabal file, however, has the following conditional dependencies:

  if flag(network-uri)
    Build-depends: network-uri == 2.6.*, network >= 2.6 && < 3.2
  else
    Build-depends: network >= 2.3 && < 2.6

  if flag(warp-tests)
    CPP-Options: -DWARP_TESTS
    build-depends:
                       case-insensitive >= 0.4.0.1 && < 1.3,
                       http-types >= 0.8.0 && < 1.0,
                       wai >= 2.1.0 && < 3.3,
                       warp >= 2.1.0 && < 3.3

    if flag(conduit10)
      build-depends:
                         conduit >= 1.0.8 && < 1.1
    else
      build-depends:
                         conduit >= 1.1 && < 1.4,
                         conduit-extra >= 1.1 && < 1.4

So with network-uri being true by default and warp-tests being true by manually specified, network, network-uri and conduit, conduit-extra were missing from MakeDepends.

[berberman]

It seems that flags will be droped (i.e., all branches of the condition tree are discarded) if they didn't be specified, even if those have default values.

[berberman]

Closed because this feature has been implemented.