Trac #34945: Refactoring tool to fix modularization anti-patterns

The new command `sage --fiximports` replaces imports from
`sage.PAC.KAGE.all` by more specific imports when `sage.PAC.KAGE` is an
implicit namespace package.

Part of Meta-ticket #34201

URL: https://trac.sagemath.org/34945
Reported by: mkoeppe
Ticket author(s): Alex Chandler, Matthias Koeppe
Reviewer(s): Matthias Koeppe, Alex Chandler

src/.relint.yml

@@ -46,7 +46,9 @@
 - name: 'namespace_pkg_all_import: import from .all of a namespace package'
   hint: |
     Sage library code should not import from sage.PAC.KAGE.all when sage.PAC.KAGE is an implicit
-    Hint: namespace package. Type import_statements("SOME_IDENTIFIER") to find a more specific import.
+    Hint: namespace package. Type import_statements("SOME_IDENTIFIER") to find a more specific import,
+    Hint: or use 'sage --fiximports' to fix automatically in the source file.
+  # Keep in sync with SAGE_ROOT/src/sage/misc/replace_dot_all.py
   pattern: 'from\s+sage(|[.](arith|categories|combinat|ext|graphs(|[.]decompositions)|interfaces|libs|matrix|misc|numerical(|[.]backends)|rings|sets))[.]all\s+import'
   filePattern: '.*[.](py|pyx|pxi)$'
   error: false # Make this a warning instead of an error for now

src/bin/sage

@@ -479,6 +479,13 @@ usage_advanced() {
         echo "                         Sage documentation for \"string\"."
         echo "  --search_src ...    -- same as --grep"
         echo "  --search_doc ...    -- same as --grepdoc"
+        echo "  --fixdoctests file.py"
+        echo "                      -- Run doctests and replace output of failing doctests"
+        echo "                         with actual output."
+        echo "  --fiximports <files|dir>"
+        echo "                      -- Replace imports from sage.PAC.KAGE.all by specific"
+        echo "                         imports when sage.PAC.KAGE is an implicit namespace"
+        echo "                         package"
     fi
     echo "  --sh [...]         -- run a shell with Sage environment variables"
     echo "                        as they are set in the runtime of Sage"
@@ -974,6 +981,11 @@ if [ "$1" = '-startuptime' -o "$1" = '--startuptime' ]; then
     exec sage-startuptime.py "$@"
 fi
 
+if [ "$1" = '-fiximports' -o "$1" = '--fiximports' ]; then
+    shift
+    exec sage-python -m sage.misc.replace_dot_all "$@"
+fi
+
 if [ "$1" = '-tox' -o "$1" = '--tox' ]; then
     shift
     if [ -n "$SAGE_SRC" -a -f "$SAGE_SRC/tox.ini" ]; then

src/doc/en/developer/packaging_sage_library.rst

@@ -274,6 +274,10 @@ distribution -- which then must be declared as a run-time dependency.
   the ``sage:`` prompt. In particular, no Sage library code should import from
   :mod:`sage.rings.all`.
 
+  To audit the Sage library for such imports, use ``sage --tox -e relint``.
+  In most cases, the imports can be fixed automatically using the
+  tool ``sage --fiximports``.
+
 - Replace module-level imports by method-level imports.  Note that
   this comes with a small runtime overhead, which can become
   noticeable if the method is called in tight inner loops.