Update developer guide for SPKGs

[jdemeyer]

This ticket is about updating the developer guide for #10492.

The developer guide suggests (http://sagemath.org/doc/developer/producing_spkgs.html#the-file-spkg-txt)

      If your package depends on another package, say boehmgc, then you should check that this other package has been installed. Your spkg-install script should check that it exists, with code like the following:

      BOEHM_GC=`cd $SAGE_ROOT/spkg/standard/; ./newest_version boehm_gc`
      if [ $? -ne 0 ]; then
          echo "Failed to find boehm_gc.  Please install the boehm_gc spkg"
          exit 1
      fi

This is totally wrong. It only checks that a spkg exists, not that it has been installed. See #12608 for removing this wrong checking from PPL.

The patches below also include various fixes to "Producing New Sage Packages".

Apply attachment: trac_12609-doc-developer.patch and attachment: 12609_review.patch to the main Sage library.

Depends on #10492

Component: documentation

Author: John Palmieri, Jeroen Demeyer

Reviewer: Jeroen Demeyer, John Palmieri

Merged: sage-5.0.beta10

Issue created by migration from https://trac.sagemath.org/ticket/12609

[jhpalmieri]

Author: John Palmieri

[jdemeyer]

comment:3

This is almost good, but you should also provide a way to check that a package has been installed, regardless of its version number. I was thinking along the lines of (not tested!)

if ! ls "$SAGE_ROOT"/spkg/installed/PACKAGE-* &>/dev/null; then
    echo >&2 "Package PACKAGE is required; please install it."
    exit 1
fi

[jhpalmieri]

comment:4

Here's a new version which uses grep. The fricas example works in my testing.

[jdemeyer]

comment:5

I guess you're missing a negation there (you're failing if the package is found).

Don't use grep -q, it's not portable. Instead use grep >/dev/null. Finally, your regular expression is probably too complicated, I think

grep '^fricas-.*' >/dev/null

should suffice. Your counterexample fricasaldor-1.0.9 doesn't match it!

To be very safe, use ls -1 instead of a plain ls.

[jhpalmieri]

comment:6

Okay, fixed.

[jdemeyer]

comment:7

Attachment: trac_12609-doc-developer.patch.gz

[jdemeyer]

Changed author from John Palmieri to John Palmieri, Jeroen Demeyer

[jdemeyer]

Reviewer: Jeroen Demeyer

[jdemeyer]

comment:8

Reviewer patch (apply on top of first patch) needs review.

[jhpalmieri]

comment:9

I wouldn't mind a change like the following, but with or with this the reviewer patch gets a positive review.

diff --git a/doc/en/developer/producing_spkgs.rst b/doc/en/developer/producing_spk
--- a/doc/en/developer/producing_spkgs.rst
+++ b/doc/en/developer/producing_spkgs.rst
@@ -34,7 +34,8 @@ Sage packages are distributed as ``.spkg
 to discourage confusion. Although Sage packages are packed using tar
 and/or bzip2, note that ``.spkg`` files contain control information
 (installation scripts and metadata) that are necessary for building
-and installing them.  When you compile Sage from a source distribution,
+and installing them.  When you compile Sage from a source
+distribution, or when you run ``sage -i <pkg>`` or ``sage -f <pkg>``,
 the file ``SAGE_ROOT/spkg/bin/sage-spkg`` takes care of the unpacking,
 compilation, and installation of Sage packages for you. You can
 type

[jhpalmieri]

Changed reviewer from Jeroen Demeyer to Jeroen Demeyer, John Palmieri

[jdemeyer]

Dependencies: #10492

[jdemeyer]

comment:11

Attachment: 12609_review.patch.gz

[jdemeyer]

Merged: sage-5.0.beta10