branch master updated: doc: Document the use of snippets vs phases.

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     new 71e746c  doc: Document the use of snippets vs phases.
71e746c is described below

commit 71e746cc63a932afea0d41652c8c297d796bccf7
Author: Maxim Cournoyer <maxim.cournoyer@gmail.com>
AuthorDate: Fri Sep 11 14:08:34 2020 -0400

    doc: Document the use of snippets vs phases.
    
    * doc/contributing.texi (Snippets versus phases): New section.
---
 doc/contributing.texi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/doc/contributing.texi b/doc/contributing.texi
index aedcb33..b18ffa1 100644
--- a/doc/contributing.texi
+++ b/doc/contributing.texi
@@ -369,6 +369,7 @@ needed is to review and apply the patch.
 * Package Naming::              What's in a name?
 * Version Numbers::             When the name is not enough.
 * Synopses and Descriptions::   Helping users find the right package.
+* Snippets versus Phases::      Whether to use a snippet, or a build phase.
 * Python Modules::              A touch of British comedy.
 * Perl Modules::                Little pearls.
 * Java Packages::               Coffee break.
@@ -599,6 +600,20 @@ Gettext}):
 for the X11 resize-and-rotate (RandR) extension. @dots{}")
 @end example
 
+@node Snippets versus Phases
+@subsection Snippets versus Phases
+
+@cindex snippets, when to use
+The boundary between using an origin snippet versus a build phase to
+modify the sources of a package can be elusive.  Origin snippets are
+typically used to remove unwanted files such as bundled libraries,
+nonfree sources, or to apply simple substitutions.  The source derived
+from an origin should produce a source that can be used to build the
+package on any system that the upstream package supports (i.e., act as
+the corresponding source).  In particular, origin snippets must not
+embed store items in the sources; such patching should rather be done
+using build phases.  Refer to the @code{origin} record documentation for
+more information (@pxref{origin Reference}).
 
 @node Python Modules
 @subsection Python Modules