From cc3ab0c214156cdad9731beb27790e8510b4b023 Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Tue, 22 Sep 2015 18:13:06 +0100
Subject: [PATCH] Add dev script for finding where functions are called from,
 and finding functions that aren't called at all

---
 scripts-dev/definitions.py | 130 +++++++++++++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)
 create mode 100755 scripts-dev/definitions.py

diff --git a/scripts-dev/definitions.py b/scripts-dev/definitions.py
new file mode 100755
index 000000000..09cec9d8e
--- /dev/null
+++ b/scripts-dev/definitions.py
@@ -0,0 +1,130 @@
+#! /usr/bin/python
+
+import ast
+import yaml
+
+class DefinitionVisitor(ast.NodeVisitor):
+    def __init__(self):
+        super(DefinitionVisitor, self).__init__()
+        self.functions = {}
+        self.classes = {}
+        self.names = {}
+        self.attrs = set()
+        self.definitions = {
+            'def': self.functions,
+            'class': self.classes,
+            'names': self.names,
+            'attrs': self.attrs,
+        }
+
+    def visit_Name(self, node):
+        self.names.setdefault(type(node.ctx).__name__, set()).add(node.id)
+
+    def visit_Attribute(self, node):
+        self.attrs.add(node.attr)
+        for child in ast.iter_child_nodes(node):
+            self.visit(child)
+
+    def visit_ClassDef(self, node):
+        visitor = DefinitionVisitor()
+        self.classes[node.name] = visitor.definitions
+        for child in ast.iter_child_nodes(node):
+            visitor.visit(child)
+
+    def visit_FunctionDef(self, node):
+        visitor = DefinitionVisitor()
+        self.functions[node.name] = visitor.definitions
+        for child in ast.iter_child_nodes(node):
+            visitor.visit(child)
+
+
+def non_empty(defs):
+    functions = {name: non_empty(f) for name, f in defs['def'].items()}
+    classes = {name: non_empty(f) for name, f in defs['class'].items()}
+    result = {}
+    if functions: result['def'] = functions
+    if classes: result['class'] = classes
+    names = defs['names']
+    uses = []
+    for name in names.get('Load', ()):
+        if name not in names.get('Param', ()) and name not in names.get('Store', ()):
+            uses.append(name)
+    uses.extend(defs['attrs'])
+    if uses: result['uses'] = uses
+    result['names'] = names
+    result['attrs'] = defs['attrs']
+    return result
+
+
+def definitions_in_code(input_code):
+    input_ast = ast.parse(input_code)
+    visitor = DefinitionVisitor()
+    visitor.visit(input_ast)
+    definitions = non_empty(visitor.definitions)
+    return definitions
+
+
+def definitions_in_file(filepath):
+    with open(filepath) as f:
+        return definitions_in_code(f.read())
+
+
+def defined_names(prefix, defs, names):
+    for name, funcs in defs.get('def', {}).items():
+        names.setdefault(name, {'defined': []})['defined'].append(prefix + name)
+        defined_names(prefix + name + ".", funcs, names)
+
+    for name, funcs in defs.get('class', {}).items():
+        names.setdefault(name, {'defined': []})['defined'].append(prefix + name)
+        defined_names(prefix + name + ".", funcs, names)
+
+
+def used_names(prefix, defs, names):
+    for name, funcs in defs.get('def', {}).items():
+        used_names(prefix + name + ".", funcs, names)
+
+    for name, funcs in defs.get('class', {}).items():
+        used_names(prefix + name + ".", funcs, names)
+
+    for used in defs.get('uses', ()):
+        if used in names:
+            names[used].setdefault('used', []).append(prefix.rstrip('.'))
+
+
+if __name__ == '__main__':
+    import sys, os
+    if not sys.argv[1:]:
+        sys.stderr.write(
+            "Usage: definitions.py <directory> <regexp>\n"
+            "       definitions.py <directory>\n"
+            "Either list the definitions matching the regexp or list\n"
+            " 'unused' definitions\n"
+        )
+
+    definitions = {}
+    for root, dirs, files in os.walk(sys.argv[1]):
+        for filename in files:
+            if filename.endswith(".py"):
+                filepath = os.path.join(root, filename)
+                definitions[filepath] = definitions_in_file(filepath)
+
+    names = {}
+    for filepath, defs in definitions.items():
+        defined_names(filepath + ":", defs, names)
+
+    for filepath, defs in definitions.items():
+        used_names(filepath + ":", defs, names)
+
+    if sys.argv[2:]:
+        import re
+        pattern = re.compile(sys.argv[2])
+        for name in list(names):
+            if not pattern.match(name):
+                del names[name]
+    else:
+        for name in list(names):
+            if 'used' in names[name]:
+                del names[name]
+
+    yaml.dump(names, sys.stdout, default_flow_style=False)
+    #yaml.dump(definitions, sys.stdout, default_flow_style=False)