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And yet another resolver bug: |
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Bug 419381 - sys-apps/portage-2.2.0_alpha109: emerge autounmask comment |
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shows confusing "required by" dependency graph |
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The problem here is as follows: |
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Assume there are three packages A, B and X on a stable system. |
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A has DEPEND="X" |
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B has DEPEND=">=X-2" |
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X-1 is stable, X-2 is not. |
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If the user tries to install A and B at the same time, emerge will |
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detect that X-2 needs to be keyworded. So far so good. |
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When it prints the autounmask message, it prints these "required by" |
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messages. It does so by traversing the dependency graph upwards. The |
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problem is with the choice of the parent of the keyworded package. |
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In the example above you want that to be B, because B is what makes X-2 |
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necessary. A could just live with the stable X-1. |
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But there is no logic to check for this. It just picks a random parent. |
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To solve this bug, you'll need to look at the following functions in the |
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depgraph class: |
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_display_autounmask |
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_get_dep_chain_as_comment |
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_get_dep_chain |
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The logic will probably be implemented in _get_dep_chain, but the other |
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function may have to pass more information down to it. |
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Note that this problem does not only affect keywording, but all other |
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things supported by --autounmask. |
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