For license compliance, the build system should detect when a new license file (of a common name format) is added to sources used in a recipe.

The current system uses digests to detect changes in the text of specific files or file fragments in order to know when a project has changed its license.  However many projects don't change existing license files, instead they add a new one (add COPYING.V3 and leave existing COPYING).  This is done for a number of reasons but a common one is that all code in the project is not changing license.

The current system could be improved by looking for files whose names match specific patterns (COPYING*, etc) and requiring that all such files be called out in meta data.  For performance reasons the depth of the file name search might have to be limited.

My basic concern is that the current system provides a false sense of security and encourages people to skip a manual or in-depth automated license review for newly included project versions if the build system does not produce a warning/error.  I question what % of license changes would really be detected by the current system.