Trac #32781: SAGE_CHECK='warn' is broken

Example of what appears at the end of some complilation:

{{{
[networkx-2.5.1]
----------------------------------------------------------------------
[networkx-2.5.1] Ran 4327 tests in 642.137s
[networkx-2.5.1]
[networkx-2.5.1] FAILED (errors=1326)
[networkx-2.5.1]
[networkx-2.5.1] real   10m53.763s
[networkx-2.5.1] user   8m59.794s
[networkx-2.5.1] sys    0m1.475s
[networkx-2.5.1]
************************************************************************
[networkx-2.5.1] Warning: Failures testing package networkx-2.5.1
(ignored)
[networkx-2.5.1]
************************************************************************
[networkx-2.5.1] Please email sage-devel (http://groups.google.com/group
/sage-devel)
[networkx-2.5.1] explaining the problem and including the log files
[networkx-2.5.1]   /opt/sagemath/sage-9.4/logs/pkgs/networkx-2.5.1.log
[networkx-2.5.1] and
[networkx-2.5.1]   /opt/sagemath/sage-9.4/config.log
[networkx-2.5.1] Describe your computer, operating system, etc.
[networkx-2.5.1] If you want to try to fix the problem yourself, *don't*
just cd to
[networkx-2.5.1]
/opt/sagemath/sage-9.4/local/var/tmp/sage/build/networkx-2.5.1 and type
'make check' or whatever is appropriate.
[networkx-2.5.1] Instead, the following commands setup all environment
variables
[networkx-2.5.1] correctly and load a subshell for you to debug the
error:
[networkx-2.5.1]   (cd
'/opt/sagemath/sage-9.4/local/var/tmp/sage/build/networkx-2.5.1' &&
'/opt/sagemath/sage-9.4/sage' --buildsh)
[networkx-2.5.1] When you are done debugging, you can type "exit" to
leave the subshell.
[networkx-2.5.1]
************************************************************************
[networkx-2.5.1] Successfully installed networkx-2.5.1
[networkx-2.5.1] Deleting temporary build directory
[networkx-2.5.1]
/opt/sagemath/sage-9.4/local/var/tmp/sage/build/networkx-2.5.1
[networkx-2.5.1] Finished installing networkx-2.5.1
make[2]: Leaving directory '/opt/sagemath/sage-9.4/build/make'

real    435m6.246s
user    1231m26.105s
sys     89m59.767s
SAGE_CHECK=warn, so scanning the log files. This may take a few seconds.
Sage build/upgrade complete!
make[1]: Leaving directory '/opt/sagemath/sage-9.4'
}}}

Nothing is reported.

For the record: the message that is added in the log in
`SAGE_ROOT/build/bin/sage-spkg` must be consistent with the pattern that
is tested in `SAGE_ROOT/build/make/install`.

URL: https://trac.sagemath.org/32781
Reported by: tmonteil
Ticket author(s): Thierry Monteil
Reviewer(s): John Palmieri

build/bin/sage-spkg

@@ -772,6 +772,7 @@ if [ "$SAGE_CHECK" = "yes" -o "$SAGE_CHECK" = "warn" ]; then
         if [ $? -ne 0 ]; then
             TEST_SUITE_RESULT="failed"
             if [ "$SAGE_CHECK" = "warn" ]; then
+                # The following warning message must be consistent with SAGE_ROOT/build/make/install (see trac:32781)
                 error_msg "Warning: Failures testing package $PKG_NAME (ignored)" "make check"
             else
                 error_msg "Error testing package $PKG_NAME" "make check"

build/make/install

@@ -122,7 +122,8 @@ EOF
 
 elif [ "$SAGE_CHECK" = "warn" ]; then
     echo "SAGE_CHECK=warn, so scanning the log files. This may take a few seconds."
-    warnings=`look_for_errors "$SAGE_LOGS/*.log" 20 "^Warning: Error testing" package`
+    # The following warning message must be consistent with SAGE_ROOT/build/bin/sage-spkg (see trac:32781)
+    warnings=`look_for_errors "$SAGE_LOGS/*.log" 20 "^Warning: Failures testing package" package`
     if [ -n "$warnings" ]; then
         cat >&2 <<EOF
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