FIX: Resolved UnboundLocalError in test_case by correctly invoking LLM and assigning to 'test_cases'.

main.py

@@ -51,43 +51,61 @@ test_prompt = ChatPromptTemplate.from_messages(
     )
 
 def test_case(code):
-    # ... (LLM generation and cleaning remains the same) ...
+    
+    # ----------------------------------------------------
+    # FIX: Define and INVOKE the test_chain to get the LLM output.
+    # This resolves the UnboundLocalError.
+    test_chain = test_prompt | llm | StrOutputParser()
+    test_cases = test_chain.invoke({"code": code})
+    # ----------------------------------------------------
 
-    # -----------------------------------------------------------
-    # (Existing cleaning and check)
+    print("\n[LOG] 1. LLM Raw Output Length:", len(test_cases))
+
+    # Aggressive cleaning
+    # Remove markdown blocks (```...```) and standalone ``` markers
     test_cases = re.sub(r"```.*?```", "", test_cases, flags=re.DOTALL)
     test_cases = re.sub(r"```", "", test_cases)
     test_cases = test_cases.strip()
 
-    # If the LLM returns nothing, force a known output
+    # Guardrail: If the LLM returns nothing, force a known output
     if not test_cases:
-        test_cases = "Error: Test case generation failed or returned empty content. Check LLM output in logs."
-    # -----------------------------------------------------------
+        test_cases = "Error: Test case generation failed or returned empty content."
+    
+    print("\n[LOG] 2. Cleaned Text (for PDF):", test_cases)
 
+    # Pass the clean UTF-8 string directly (resolves FPDF encoding issues)
     safe_text = test_cases
+    
     pdf = FPDF()
     pdf.add_page()
     
-    # ... (FPDF Unicode font setup remains the same) ...
-    
+    # FPDF FIX: Add and use a Unicode-compatible font (DejaVuSans)
+    try:
+        # Path where the font is installed via the Dockerfile's apt-get command
+        pdf.add_font("DejaVuSans", style="", fname="/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf")
+        pdf.set_font("DejaVuSans", size=12)
+    except Exception as e:
+        print(f"[LOG] FPDF Font Error: {e}. Falling back to Arial.")
+        pdf.set_font("Arial", size=12)
+
+    # Set title and content cell
     pdf.multi_cell(0, 10, txt="--- Generated Test Cases ---", align='C')
     pdf.multi_cell(0, 10, txt=safe_text)
     
-    
     # -----------------------------------------------------------
-    # CRITICAL CHANGE: Get bytes object directly from FPDF2
+    # CRITICAL CHANGE: Get bytes object directly from FPDF2 with error handling
     try:
-        # dest='S' returns a string in FPDF2. We need to encode this string.
+        # dest='S' returns a string in FPDF2. We encode this string.
         pdf_string = pdf.output(dest='S')
-        pdf_bytes = pdf_string.encode('latin-1')
+        pdf_bytes = pdf_string.encode('latin-1', 'replace')
+        
+        print("\n[LOG] 3. PDF Bytes Length:", len(pdf_bytes))
         
-        # Check to ensure the file is not empty before returning
+        # Check to ensure the file is not empty (e.g., must be > 100 bytes)
         if len(pdf_bytes) < 100:
             print("[CRITICAL LOG] FPDF generated very small file, likely failed.")
-            # Return a non-empty, guaranteed failure PDF to force the button to display
-            # This is a temporary diagnostic tool.
             
-            # Recreate PDF with ONLY the error message
+            # Fallback PDF: Creates a new PDF with the error message
             error_pdf = FPDF()
             error_pdf.add_page()
             error_pdf.set_font("Arial", size=12)
@@ -98,7 +116,7 @@ def test_case(code):
         
     except Exception as e:
         print(f"[FATAL LOG] PDF output failed with error: {e}")
-        # Return a guaranteed failure PDF to force button display
+        # Fatal Fallback PDF: Creates a new PDF with the fatal error message
         error_pdf = FPDF()
         error_pdf.add_page()
         error_pdf.set_font("Arial", size=12)