Added delete option to database storage.

venv/Lib/site-packages/pycparser/ast_transforms.py

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+#------------------------------------------------------------------------------
+# pycparser: ast_transforms.py
+#
+# Some utilities used by the parser to create a friendlier AST.
+#
+# Eli Bendersky [https://eli.thegreenplace.net/]
+# License: BSD
+#------------------------------------------------------------------------------
+
+from . import c_ast
+
+
+def fix_switch_cases(switch_node):
+    """ The 'case' statements in a 'switch' come out of parsing with one
+        child node, so subsequent statements are just tucked to the parent
+        Compound. Additionally, consecutive (fall-through) case statements
+        come out messy. This is a peculiarity of the C grammar. The following:
+
+            switch (myvar) {
+                case 10:
+                    k = 10;
+                    p = k + 1;
+                    return 10;
+                case 20:
+                case 30:
+                    return 20;
+                default:
+                    break;
+            }
+
+        Creates this tree (pseudo-dump):
+
+            Switch
+                ID: myvar
+                Compound:
+                    Case 10:
+                        k = 10
+                    p = k + 1
+                    return 10
+                    Case 20:
+                        Case 30:
+                            return 20
+                    Default:
+                        break
+
+        The goal of this transform is to fix this mess, turning it into the
+        following:
+
+            Switch
+                ID: myvar
+                Compound:
+                    Case 10:
+                        k = 10
+                        p = k + 1
+                        return 10
+                    Case 20:
+                    Case 30:
+                        return 20
+                    Default:
+                        break
+
+        A fixed AST node is returned. The argument may be modified.
+    """
+    assert isinstance(switch_node, c_ast.Switch)
+    if not isinstance(switch_node.stmt, c_ast.Compound):
+        return switch_node
+
+    # The new Compound child for the Switch, which will collect children in the
+    # correct order
+    new_compound = c_ast.Compound([], switch_node.stmt.coord)
+
+    # The last Case/Default node
+    last_case = None
+
+    # Goes over the children of the Compound below the Switch, adding them
+    # either directly below new_compound or below the last Case as appropriate
+    # (for `switch(cond) {}`, block_items would have been None)
+    for child in (switch_node.stmt.block_items or []):
+        if isinstance(child, (c_ast.Case, c_ast.Default)):
+            # If it's a Case/Default:
+            # 1. Add it to the Compound and mark as "last case"
+            # 2. If its immediate child is also a Case or Default, promote it
+            #    to a sibling.
+            new_compound.block_items.append(child)
+            _extract_nested_case(child, new_compound.block_items)
+            last_case = new_compound.block_items[-1]
+        else:
+            # Other statements are added as children to the last case, if it
+            # exists.
+            if last_case is None:
+                new_compound.block_items.append(child)
+            else:
+                last_case.stmts.append(child)
+
+    switch_node.stmt = new_compound
+    return switch_node
+
+
+def _extract_nested_case(case_node, stmts_list):
+    """ Recursively extract consecutive Case statements that are made nested
+        by the parser and add them to the stmts_list.
+    """
+    if isinstance(case_node.stmts[0], (c_ast.Case, c_ast.Default)):
+        stmts_list.append(case_node.stmts.pop())
+        _extract_nested_case(stmts_list[-1], stmts_list)
+