simplified

test_jinja2_analysis.py

@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+"""Explore Jinja2's AST to understand variable detection in conditionals"""
+
+from jinja2 import Environment, meta, nodes
+
+# Test different template patterns
+templates = [
+    # Simple required variable
+    ("simple", "Hello {{ name }}!"),
+
+    # Variable in conditional (optional)
+    ("conditional", """{% if error %}
+Error: {{ error }}
+{% endif %}"""),
+
+    # Mixed required and optional
+    ("mixed", """Status: {{ status }}
+{% if error %}
+Error: {{ error }}
+{% endif %}"""),
+
+    # Nested conditionals
+    ("nested", """{% if user %}
+Name: {{ user.name }}
+{% if user.email %}
+Email: {{ user.email }}
+{% endif %}
+{% endif %}"""),
+
+    # Variable with default filter (makes it optional)
+    ("default_filter", "Hello {{ name | default('Guest') }}!"),
+
+    # Variable in for loop
+    ("for_loop", """{% for item in items %}
+- {{ item }}
+{% endfor %}"""),
+
+    # Complex with multiple contexts
+    ("complex", """Required: {{ required }}
+{% if optional1 %}
+Optional1: {{ optional1 }}
+{% endif %}
+Default: {{ optional2 | default('N/A') }}
+{% for item in items %}
+- {{ item }}
+{% endfor %}""")
+]
+
+env = Environment()
+
+print("=" * 70)
+print("Analyzing Jinja2 AST for Variable Detection")
+print("=" * 70)
+
+for name, template in templates:
+    print(f"\n{name.upper()} TEMPLATE:")
+    print("-" * 40)
+    print(template)
+    print("-" * 40)
+
+    # Parse the template
+    ast = env.parse(template)
+
+    # Get undeclared variables (what we currently use)
+    undeclared = meta.find_undeclared_variables(ast)
+    print(f"Undeclared variables: {undeclared}")
+
+    # Try to analyze the AST more deeply
+    print("\nAST Analysis:")
+
+    def analyze_node(node, indent=0, context="root"):
+        """Recursively analyze AST nodes"""
+        prefix = "  " * indent
+
+        if isinstance(node, nodes.Name):
+            print(f"{prefix}Variable '{node.name}' in context: {context}")
+
+        elif isinstance(node, nodes.If):
+            print(f"{prefix}If block:")
+            print(f"{prefix}  Test expression:")
+            analyze_node(node.test, indent + 2, "if_test")
+            print(f"{prefix}  Body:")
+            for child in node.body:
+                analyze_node(child, indent + 2, "if_body")
+            if node.elif_:
+                print(f"{prefix}  Elif:")
+                for child in node.elif_:
+                    analyze_node(child, indent + 2, "elif")
+            if node.else_:
+                print(f"{prefix}  Else:")
+                for child in node.else_:
+                    analyze_node(child, indent + 2, "else")
+
+        elif isinstance(node, nodes.For):
+            print(f"{prefix}For loop:")
+            print(f"{prefix}  Target: {node.target}")
+            print(f"{prefix}  Iter:")
+            analyze_node(node.iter, indent + 2, "for_iter")
+            print(f"{prefix}  Body:")
+            for child in node.body:
+                analyze_node(child, indent + 2, "for_body")
+
+        elif isinstance(node, nodes.Filter):
+            print(f"{prefix}Filter: {node.name}")
+            if node.name == "default":
+                print(f"{prefix}  (Makes variable optional!)")
+            analyze_node(node.node, indent + 1, f"filter_{node.name}")
+
+        elif isinstance(node, nodes.Getattr):
+            print(f"{prefix}Attribute access: .{node.attr}")
+            analyze_node(node.node, indent + 1, "getattr")
+
+        elif isinstance(node, nodes.Output):
+            print(f"{prefix}Output:")
+            for child in node.nodes:
+                analyze_node(child, indent + 1, "output")
+
+        elif isinstance(node, nodes.TemplateData):
+            # Skip raw text
+            pass
+
+        else:
+            # Recurse into child nodes
+            for child in node.iter_child_nodes():
+                analyze_node(child, indent, context)
+
+    analyze_node(ast)
+
+print("\n" + "=" * 70)
+print("INSIGHTS:")
+print("-" * 70)
+print("""
+1. Jinja2's `find_undeclared_variables()` returns ALL variables, regardless of context
+2. Variables in {% if %} conditions could be considered optional
+3. Variables with | default() filter are definitely optional
+4. We can walk the AST to identify context for each variable
+
+Possible solution:
+- Walk the AST to categorize variables by context
+- Mark variables in if_test contexts as optional (unless also used elsewhere)
+- Mark variables with default filter as optional
+- Consider all others as required
+""")