Stylistic fixes: triple-quoted docstrings, more comments (ae6ffd2e) · Commits · Dom Sekotill / django

django/db/backends/schema.py

+21 −7

Original line number	Diff line number	Diff line
		@@ -59,21 +59,27 @@ class BaseDatabaseSchemaEditor(object):
		# State-managing methods

		def start(self):
		"Marks the start of a schema-altering run"
		"""
		Marks the start of a schema-altering run.
		"""
		self.deferred_sql = []
		self.connection.commit_unless_managed()
		self.connection.enter_transaction_management()
		self.connection.managed(True)

		def commit(self):
		"Finishes a schema-altering run"
		"""
		Finishes a schema-altering run.
		"""
		for sql in self.deferred_sql:
		self.execute(sql)
		self.connection.commit()
		self.connection.leave_transaction_management()

		def rollback(self):
		"Tries to roll back a schema-altering run. Call instead of commit()"
		"""
		Tries to roll back a schema-altering run. Call instead of commit().
		"""
		if not self.connection.features.can_rollback_ddl:
		raise RuntimeError("Cannot rollback schema changes on this backend")
		self.connection.rollback()
		@@ -137,7 +143,9 @@ class BaseDatabaseSchemaEditor(object):
		return sql, params

		def effective_default(self, field):
		"Returns a field's effective database default value"
		"""
		Returns a field's effective database default value
		"""
		if field.has_default():
		default = field.get_default()
		elif not field.null and field.blank and field.empty_strings_allowed:
		@@ -580,7 +588,9 @@ class BaseDatabaseSchemaEditor(object):
		)

		def _alter_many_to_many(self, model, old_field, new_field, strict):
		"Alters M2Ms to repoint their to= endpoints."
		"""
		Alters M2Ms to repoint their to= endpoints.
		"""
		# Rename the through table
		self.alter_db_table(old_field.rel.through, old_field.rel.through._meta.db_table, new_field.rel.through._meta.db_table)
		# Repoint the FK to the other side
		@@ -591,7 +601,9 @@ class BaseDatabaseSchemaEditor(object):
		)

		def _create_index_name(self, model, column_names, suffix=""):
		"Generates a unique name for an index/unique constraint."
		"""
		Generates a unique name for an index/unique constraint.
		"""
		# If there is just one column in the index, use a default algorithm from Django
		if len(column_names) == 1 and not suffix:
		return truncate_name(
		@@ -609,7 +621,9 @@ class BaseDatabaseSchemaEditor(object):
		return index_name

		def _constraint_names(self, model, column_names=None, unique=None, primary_key=None, index=None, foreign_key=None, check=None):
		"Returns all constraint names matching the columns and conditions"
		"""
		Returns all constraint names matching the columns and conditions
		"""
		column_names = set(column_names) if column_names else None
		constraints = self.connection.introspection.get_constraints(self.connection.cursor(), model._meta.db_table)
		result = []

django/db/backends/sqlite3/introspection.py

+4 −1

Original line number	Diff line number	Diff line
		@@ -207,10 +207,13 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
		# Get the PK
		pk_column = self.get_primary_key_column(cursor, table_name)
		if pk_column:
		# SQLite doesn't actually give a name to the PK constraint,
		# so we invent one. This is fine, as the SQLite backend never
		# deletes PK constraints by name.
		constraints["__primary__"] = {
		"columns": set([pk_column]),
		"primary_key": True,
		"unique": False, # It's not actually a unique constraint
		"unique": False, # It's not actually a unique constraint.
		"foreign_key": False,
		"check": False,
		"index": False,

django/db/backends/sqlite3/schema.py

+18 −3

Original line number	Diff line number	Diff line
		@@ -8,7 +8,9 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
		sql_delete_table = "DROP TABLE %(table)s"

		def _remake_table(self, model, create_fields=[], delete_fields=[], alter_fields=[], rename_fields=[], override_uniques=None):
		"Shortcut to transform a model from old_model into new_model"
		"""
		Shortcut to transform a model from old_model into new_model
		"""
		# Work out the new fields dict / mapping
		body = dict((f.name, f) for f in model._meta.local_fields)
		mapping = dict((f.column, f.column) for f in model._meta.local_fields)
		@@ -98,7 +100,13 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
		self._remake_table(model, delete_fields=[field])

		def alter_field(self, model, old_field, new_field, strict=False):
		# Ensure this field is even column-based
		"""
		Allows a field's type, uniqueness, nullability, default, column,
		constraints etc. to be modified.
		Requires a copy of the old field as well so we can only perform
		changes that are required.
		If strict is true, raises errors if the old column does not match old_field precisely.
		"""
		old_db_params = old_field.db_parameters(connection=self.connection)
		old_type = old_db_params['type']
		new_db_params = new_field.db_parameters(connection=self.connection)
		@@ -114,10 +122,17 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
		self._remake_table(model, alter_fields=[(old_field, new_field)])

		def alter_unique_together(self, model, old_unique_together, new_unique_together):
		"""
		Deals with a model changing its unique_together.
		Note: The input unique_togethers must be doubly-nested, not the single-
		nested ["foo", "bar"] format.
		"""
		self._remake_table(model, override_uniques=new_unique_together)

		def _alter_many_to_many(self, model, old_field, new_field, strict):
		"Alters M2Ms to repoint their to= endpoints."
		"""
		Alters M2Ms to repoint their to= endpoints.
		"""
		# Make a new through table
		self.create_model(new_field.rel.through)
		# Copy the data across