finding package with components that have a dependent relationship is tricky

[osrf-migration]

Original report (archived issue) by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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Prerequisites

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  • Checked the Q&A board for common solutions: http://answers.gazebosim.org
  • Checked that your issue isn't already filed.
  • Checked that there is not already an Ignition package that provides the described functionality: https://ignitionrobotics.org/libs

Description

If a package has components with a dependency relationship (such as ign-physics-dartsim-plugin, which depends on ignition-physics-sdf and ignition-physics-mesh), then then all the components must be listed in the ign_find_package call and in a proper order. The following is a workaround for this issue in ign-gazebo:

• https://osrf-migration.github.io/ignition-gh-pages/#!/ignitionrobotics/ign-gazebo/pull-requests/105/find-mesh-component-of-physics/diff

Steps to Reproduce

I've demonstrated this issue with some examples committed to branch find_component_order_working and branch find_component_order. The find_component_order_working branch creates a package component_deps that has two components: parent and child, and the child component links against the parent. There is a second package called use_component_deps1 that makes an ign_find_package call for component_deps specifying both components parent child. This example builds fine:

1. hg up find_component_order_working
2. mkdir build && cd build && cmake ..
3. make (successful)

Now on branch branch find_component_order, another example named use_component_deps2 is added that differs from use_component_deps1 only in the order that components are specified in the ign_find_package call, but it fails to build:

1. hg up find_component_order
2. mkdir build && cd build && cmake ..
3. make (unsuccessful)

Expected behavior:

I would expect the examples to build regardless of the order in which components are specified. Furthermore, I would that specifying a component would cause dependent components to be included as well (as in the ign-physics example mentioned above).

Actual behavior:

ign_find_package is sensitive to the order of specified components when there is a dependent relationship, and dependent components must all be listed.

Reproduces how often:

100%

Versions

ign-cmake1 and ign-cmake2

Additional Information

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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• Edited issue description

[osrf-migration]

Original comment by Michael Grey (Bitbucket: mxgrey, GitHub: mxgrey).

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Pull request #131 should fix this now.

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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• changed state from "new" to "resolved"

pull request #131