# FeatureSummary

Macros for generating a summary of enabled/disabled features

This module provides the macros feature_summary(), set_package_properties() and add_feature_info(). For compatibility it also still provides set_package_info(), set_feature_info(), print_enabled_features() and print_disabled_features().

These macros can be used to generate a summary of enabled and disabled packages and/or feature for a build tree:

    -- The following OPTIONAL packages have been found:
    LibXml2 (required version >= 2.4), XML processing lib, <http://xmlsoft.org>
       * Enables HTML-import in MyWordProcessor
       * Enables odt-export in MyWordProcessor
    PNG , A PNG image library. , <http://www.libpng.org/pub/png/>
       * Enables saving screenshots
    -- The following OPTIONAL packages have not been found:
    Lua51 , The Lua scripting language. , <http://www.lua.org>
       * Enables macros in MyWordProcessor
    Foo , Foo provides cool stuff.

    FEATURE_SUMMARY( [FILENAME <file>]
                     [APPEND]
                     [VAR <variable_name>]
                     [INCLUDE_QUIET_PACKAGES]
                     [FATAL_ON_MISSING_REQUIRED_PACKAGES]
                     [DESCRIPTION "Found packages:"]
                     WHAT (ALL | PACKAGES_FOUND | PACKAGES_NOT_FOUND
                          | ENABLED_FEATURES | DISABLED_FEATURES)
                   )

The FEATURE_SUMMARY() macro can be used to print information about enabled or disabled packages or features of a project. By default, only the names of the features/packages will be printed and their required version when one was specified. Use SET_PACKAGE_PROPERTIES() to add more useful information, like e.g. a download URL for the respective package or their purpose in the project.

The WHAT option is the only mandatory option. Here you specify what information will be printed:

`ALL`
  print everything
`ENABLED_FEATURES`
  the list of all features which are enabled
`DISABLED_FEATURES`
  the list of all features which are disabled
`PACKAGES_FOUND`
  the list of all packages which have been found
`PACKAGES_NOT_FOUND`
  the list of all packages which have not been found
`OPTIONAL_PACKAGES_FOUND`
  only those packages which have been found which have the type OPTIONAL
`OPTIONAL_PACKAGES_NOT_FOUND`
  only those packages which have not been found which have the type OPTIONAL
`RECOMMENDED_PACKAGES_FOUND`
  only those packages which have been found which have the type RECOMMENDED
`RECOMMENDED_PACKAGES_NOT_FOUND`
  only those packages which have not been found which have the type RECOMMENDED
`REQUIRED_PACKAGES_FOUND`
  only those packages which have been found which have the type REQUIRED
`REQUIRED_PACKAGES_NOT_FOUND`
  only those packages which have not been found which have the type REQUIRED
`RUNTIME_PACKAGES_FOUND`
  only those packages which have been found which have the type RUNTIME
`RUNTIME_PACKAGES_NOT_FOUND`
  only those packages which have not been found which have the type RUNTIME

With the exception of the `ALL` value, these values can be combined in order to customize the output. For example:

    feature_summary(WHAT ENABLED_FEATURES DISABLED_FEATURES)

If a FILENAME is given, the information is printed into this file. If APPEND is used, it is appended to this file, otherwise the file is overwritten if it already existed. If the VAR option is used, the information is “printed” into the specified variable. If FILENAME is not used, the information is printed to the terminal. Using the DESCRIPTION option a description or headline can be set which will be printed above the actual content. If INCLUDE_QUIET_PACKAGES is given, packages which have been searched with find_package(... QUIET) will also be listed. By default they are skipped. If FATAL_ON_MISSING_REQUIRED_PACKAGES is given, CMake will abort if a package which is marked as REQUIRED has not been found.

Example 1, append everything to a file:

    feature_summary(WHAT ALL
                    FILENAME ${CMAKE_BINARY_DIR}/all.log APPEND)

Example 2, print the enabled features into the variable enabledFeaturesText, including QUIET packages:

    feature_summary(WHAT ENABLED_FEATURES
                    INCLUDE_QUIET_PACKAGES
                    DESCRIPTION "Enabled Features:"
                    VAR enabledFeaturesText)
    message(STATUS "${enabledFeaturesText}")

    SET_PACKAGE_PROPERTIES(<name> PROPERTIES
                           [ URL <url> ]
                           [ DESCRIPTION <description> ]
                           [ TYPE (RUNTIME|OPTIONAL|RECOMMENDED|REQUIRED) ]
                           [ PURPOSE <purpose> ]
                          )

Use this macro to set up information about the named package, which can then be displayed via FEATURE_SUMMARY(). This can be done either directly in the Find-module or in the project which uses the module after the find_package() call. The features for which information can be set are added automatically by the find_package() command.

URL: this should be the homepage of the package, or something similar. Ideally this is set already directly in the Find-module.

DESCRIPTION: A short description what that package is, at most one sentence. Ideally this is set already directly in the Find-module.

TYPE: What type of dependency has the using project on that package. Default is OPTIONAL. In this case it is a package which can be used by the project when available at buildtime, but it also work without. RECOMMENDED is similar to OPTIONAL, i.e. the project will build if the package is not present, but the functionality of the resulting binaries will be severly limited. If a REQUIRED package is not available at buildtime, the project may not even build. This can be combined with the FATAL_ON_MISSING_REQUIRED_PACKAGES argument for feature_summary(). Last, a RUNTIME package is a package which is actually not used at all during the build, but which is required for actually running the resulting binaries. So if such a package is missing, the project can still be built, but it may not work later on. If set_package_properties() is called multiple times for the same package with different TYPEs, the TYPE is only changed to higher TYPEs ( RUNTIME < OPTIONAL < RECOMMENDED < REQUIRED ), lower TYPEs are ignored. The TYPE property is project-specific, so it cannot be set by the Find-module, but must be set in the project.

PURPOSE: This describes which features this package enables in the project, i.e. it tells the user what functionality he gets in the resulting binaries. If set_package_properties() is called multiple times for a package, all PURPOSE properties are appended to a list of purposes of the package in the project. As the TYPE property, also the PURPOSE property is project-specific, so it cannot be set by the Find-module, but must be set in the project.

Example for setting the info for a package:

    find_package(LibXml2)
    set_package_properties(LibXml2 PROPERTIES
                           DESCRIPTION "A XML processing library."
                           URL "http://xmlsoft.org/")

    set_package_properties(LibXml2 PROPERTIES
                           TYPE RECOMMENDED
                           PURPOSE "Enables HTML-import in MyWordProcessor")
    ...
    set_package_properties(LibXml2 PROPERTIES
                           TYPE OPTIONAL
                           PURPOSE "Enables odt-export in MyWordProcessor")

    find_package(DBUS)
    set_package_properties(DBUS PROPERTIES
      TYPE RUNTIME
      PURPOSE "Necessary to disable the screensaver during a presentation" )

    ADD_FEATURE_INFO(<name> <enabled> <description>)

Use this macro to add information about a feature with the given <name>. <enabled> contains whether this feature is enabled or not, <description> is a text describing the feature. The information can be displayed using feature_summary() for ENABLED_FEATURES and DISABLED_FEATURES respectively.

Example for setting the info for a feature:

    option(WITH_FOO "Help for foo" ON)
    add_feature_info(Foo WITH_FOO "The Foo feature provides very cool stuff.")

The following macros are provided for compatibility with previous CMake versions:

    SET_PACKAGE_INFO(<name> <description> [<url> [<purpose>] ] )

Use this macro to set up information about the named package, which can then be displayed via FEATURE_SUMMARY(). This can be done either directly in the Find-module or in the project which uses the module after the find_package() call. The features for which information can be set are added automatically by the find_package() command.

    PRINT_ENABLED_FEATURES()

Does the same as FEATURE_SUMMARY(WHAT ENABLED_FEATURES DESCRIPTION “Enabled features:”)

    PRINT_DISABLED_FEATURES()

Does the same as FEATURE_SUMMARY(WHAT DISABLED_FEATURES DESCRIPTION “Disabled features:”)

    SET_FEATURE_INFO(<name> <description> [<url>] )

Does the same as SET_PACKAGE_INFO(<name> <description> <url> )