Remove all remaining text() coercions and ensure identifiers are safe

Fully removed the behavior of strings passed directly as components of a
:func:`.select` or :class:`.Query` object being coerced to :func:`.text`
constructs automatically; the warning that has been emitted is now an
ArgumentError or in the case of order_by() / group_by() a CompileError.
This has emitted a warning since version 1.0 however its presence continues
to create concerns for the potential of mis-use of this behavior.

Note that public CVEs have been posted for order_by() / group_by() which
are resolved by this commit:  CVE-2019-7164  CVE-2019-7548

Added "SQL phrase validation" to key DDL phrases that are accepted as plain
strings, including :paramref:`.ForeignKeyConstraint.on_delete`,
:paramref:`.ForeignKeyConstraint.on_update`,
:paramref:`.ExcludeConstraint.using`,
:paramref:`.ForeignKeyConstraint.initially`, for areas where a series of SQL
keywords only are expected.Any non-space characters that suggest the phrase
would need to be quoted will raise a :class:`.CompileError`.   This change
is related to the series of changes committed as part of :ticket:`4481`.

Fixed issue where using an uppercase name for an index type (e.g. GIST,
BTREE, etc. ) or an EXCLUDE constraint would treat it as an identifier to
be quoted, rather than rendering it as is. The new behavior converts these
types to lowercase and ensures they contain only valid SQL characters.

Quoting is applied to :class:`.Function` names, those which are usually but
not necessarily generated from the :attr:`.sql.func` construct,  at compile
time if they contain illegal characters, such as spaces or punctuation. The
names are as before treated as case insensitive however, meaning if the
names contain uppercase or mixed case characters, that alone does not
trigger quoting. The case insensitivity is currently maintained for
backwards compatibility.

Fixes: #4481
Fixes: #4473
Fixes: #4467
Change-Id: Ib22a27d62930e24702e2f0f7c74a0473385a08eb

1 files changed, 80 insertions, 0 deletions

diff --git a/lib/sqlalchemy/util/langhelpers.py b/lib/sqlalchemy/util/langhelpers.py
index bfe3fd275..198a23a59 100644
--- a/lib/sqlalchemy/util/langhelpers.py
+++ b/lib/sqlalchemy/util/langhelpers.py
@@ -16,6 +16,7 @@ import itertools
 import operator
 import re
 import sys
+import textwrap
 import types
 import warnings
 
@@ -1572,3 +1573,82 @@ def quoted_token_parser(value):
         idx += 1
 
     return ["".join(token) for token in result]
+
+
+def add_parameter_text(params, text):
+    params = _collections.to_list(params)
+
+    def decorate(fn):
+        doc = fn.__doc__ is not None and fn.__doc__ or ""
+        if doc:
+            doc = inject_param_text(doc, {param: text for param in params})
+        fn.__doc__ = doc
+        return fn
+
+    return decorate
+
+
+def _dedent_docstring(text):
+    split_text = text.split("\n", 1)
+    if len(split_text) == 1:
+        return text
+    else:
+        firstline, remaining = split_text
+    if not firstline.startswith(" "):
+        return firstline + "\n" + textwrap.dedent(remaining)
+    else:
+        return textwrap.dedent(text)
+
+
+def inject_docstring_text(doctext, injecttext, pos):
+    doctext = _dedent_docstring(doctext or "")
+    lines = doctext.split("\n")
+    injectlines = textwrap.dedent(injecttext).split("\n")
+    if injectlines[0]:
+        injectlines.insert(0, "")
+
+    blanks = [num for num, line in enumerate(lines) if not line.strip()]
+    blanks.insert(0, 0)
+
+    inject_pos = blanks[min(pos, len(blanks) - 1)]
+
+    lines = lines[0:inject_pos] + injectlines + lines[inject_pos:]
+    return "\n".join(lines)
+
+
+def inject_param_text(doctext, inject_params):
+    doclines = doctext.splitlines()
+    lines = []
+
+    to_inject = None
+    while doclines:
+        line = doclines.pop(0)
+        if to_inject is None:
+            m = re.match(r"(\s+):param (?:\\\*\*?)?(.+?):", line)
+            if m:
+                param = m.group(2)
+                if param in inject_params:
+                    # default indent to that of :param: plus one
+                    indent = " " * len(m.group(1)) + " "
+
+                    # but if the next line has text, use that line's
+                    # indentntation
+                    if doclines:
+                        m2 = re.match(r"(\s+)\S", doclines[0])
+                        if m2:
+                            indent = " " * len(m2.group(1))
+
+                    to_inject = indent + inject_params[param]
+        elif line.lstrip().startswith(":param "):
+            lines.append("\n")
+            lines.append(to_inject)
+            lines.append("\n")
+            to_inject = None
+        elif not line.rstrip():
+            lines.append(line)
+            lines.append(to_inject)
+            lines.append("\n")
+            to_inject = None
+        lines.append(line)
+
+    return "\n".join(lines)