function deps

.travis.yml

@@ -14,7 +14,7 @@ addons:
   postgresql: "9.6"
 
 # command to install dependencies
-install: make pipupgrade
+install: make pip
 
 # command to run tests
 script: make test

migra/changes.py

@@ -24,11 +24,19 @@ def statements_for_changes(
         creations_only=False,
         drops_only=False,
         modifications=True,
-        dependency_ordering=False):
+        dependency_ordering=False,
+        add_dependents_for_modified=False):
 
-    added, removed, modified, _ = \
+    added, removed, modified, unmodified = \
         differences(things_from, things_target)
 
+    if add_dependents_for_modified:
+        for k, m in list(modified.items()):
+            for d in m.dependents_all:
+                if d in unmodified:
+                    modified[d] = unmodified.pop(d)
+        modified = od(sorted(modified.items()))
+
     statements = Statements()
 
     if not creations_only:
@@ -212,7 +220,11 @@ class Changes(object):
             avf = od(sorted(avf))
             bvf = od(sorted(bvf))
 
-            return partial(statements_for_changes, avf, bvf)
+            return partial(
+                statements_for_changes,
+                avf,
+                bvf,
+                add_dependents_for_modified=True)
         elif name in THINGS:
             return partial(
                 statements_for_changes,

migra/migra.py

@@ -7,6 +7,9 @@ from .statements import Statements
 
 
 class Migration(object):
+    """
+    The main class of migra
+    """
     def __init__(self, x_from, x_target):
         self.statements = Statements()
         self.changes = Changes(None, None)

migra/util.py

@@ -3,7 +3,8 @@ from __future__ import unicode_literals
 from collections import OrderedDict as od
 
 
-def differences(a, b):
+def differences(a, b, add_dependencies_for_modifications=True):
+
     a_keys = set(a.keys())
     b_keys = set(b.keys())
 

tests/FIXTURES/dependencies/a.sql

@@ -6,6 +6,10 @@ create view bbb_view2 as select name from aaa_view1;
 
 create view ccc_view3 as select name from bbb_view2;
 
+create view ddd_changed as select name from basetable;
+
+create view ddd_unchanged as select name from ddd_changed;
+
 create or replace function "public"."depends_on_bbb_view2"(t text)
 returns TABLE(x text) as
 $$ select * from bbb_view2 $$

tests/FIXTURES/dependencies/b.sql

@@ -1 +1,5 @@
+create table basetable(id serial primary key, name text);
 
+create view ddd_changed as select name, 'x' as x from basetable;
+
+create view ddd_unchanged as select name from ddd_changed;

tests/FIXTURES/dependencies/expected.sql

@@ -1,15 +1,19 @@
-alter table "public"."basetable" drop constraint "basetable_pkey";
-
-drop index if exists "public"."basetable_pkey";
-
 drop view if exists "public"."ccc_view3" cascade;
 
 drop function if exists "public"."depends_on_bbb_view2"(t text) cascade;
 
+drop view if exists "public"."ddd_unchanged" cascade;
+
 drop view if exists "public"."bbb_view2" cascade;
 
+drop view if exists "public"."ddd_changed" cascade;
+
 drop view if exists "public"."aaa_view1" cascade;
 
-drop table "public"."basetable";
+create view "public"."ddd_changed" as  SELECT basetable.name,
+    'x' AS x
+   FROM basetable;
 
-drop sequence if exists "public"."basetable_id_seq";
+
+create view "public"."ddd_unchanged" as  SELECT ddd_changed.name
+   FROM ddd_changed;

tests/FIXTURES/dependencies/expected2.sql

@@ -1,21 +1,25 @@
-alter table "public"."basetable" drop constraint "basetable_pkey";
-
-drop index if exists "public"."basetable_pkey";
-
 drop view if exists "public"."ccc_view3" cascade;
 
-drop view if exists "public"."ddd" cascade;
-
 drop function if exists "public"."depends_on_bbb_view2"(t text) cascade;
 
 drop view if exists "public"."eee" cascade;
 
 drop function if exists "public"."fff"(t text) cascade;
 
+drop view if exists "public"."ddd_unchanged" cascade;
+
 drop view if exists "public"."bbb_view2" cascade;
 
+drop view if exists "public"."ddd" cascade;
+
+drop view if exists "public"."ddd_changed" cascade;
+
 drop view if exists "public"."aaa_view1" cascade;
 
-drop table "public"."basetable";
+create view "public"."ddd_changed" as  SELECT basetable.name,
+    'x' AS x
+   FROM basetable;
 
-drop sequence if exists "public"."basetable_id_seq";
+
+create view "public"."ddd_unchanged" as  SELECT ddd_changed.name
+   FROM ddd_changed;

tests/test_migra.py

@@ -87,7 +87,8 @@ def do_fixture_test(fixture_name):
                 m.add_sql(ADDITIONS)
                 m.apply()
                 m.add_all_changes()
-
+                print('x')
+                print(m.sql.strip())
                 assert m.sql.strip() == EXPECTED2  # sql generated OK
                 m.apply()