Avoid linecache unique file generation in case of linecache disabled

HISTORY.md

@@ -4,6 +4,7 @@
 
 - Fix a regression when unstructuring `Any | None`.
   ([#453](https://github.com/python-attrs/cattrs/issues/453))
+- Generate unique files only in case of linecache enabled. ([#445](https://github.com/python-attrs/cattrs/issues/445) [#441](https://github.com/python-attrs/cattrs/pull/461))
 
 ## 23.2.1 (2023-11-18)
 

src/cattrs/gen/__init__.py

@@ -212,22 +212,20 @@ def make_dict_unstructure_fn(
             + ["  return res"]
         )
         script = "\n".join(total_lines)
-
-        fname = generate_unique_filename(
-            cl, "unstructure", reserve=_cattrs_use_linecache
-        )
-
-        eval(compile(script, fname, "exec"), globs)
-
-        fn = globs[fn_name]
+        fname = ""
         if _cattrs_use_linecache:
+            fname = generate_unique_filename(
+                cl, "unstructure", reserve=_cattrs_use_linecache
+            )
             linecache.cache[fname] = len(script), None, total_lines, fname
+
+        eval(compile(script, fname, "exec"), globs)
     finally:
         working_set.remove(cl)
         if not working_set:
             del already_generating.working_set
 
-    return fn
+    return globs[fn_name]
 
 
 DictStructureFn = Callable[[Mapping[str, Any], Any], T]
@@ -628,12 +626,14 @@ def make_dict_structure_fn(
         *pi_lines,
     ]
 
-    fname = generate_unique_filename(cl, "structure", reserve=_cattrs_use_linecache)
     script = "\n".join(total_lines)
-    eval(compile(script, fname, "exec"), globs)
+    fname = ""
     if _cattrs_use_linecache:
+        fname = generate_unique_filename(cl, "structure", reserve=_cattrs_use_linecache)
         linecache.cache[fname] = len(script), None, total_lines, fname
 
+    eval(compile(script, fname, "exec"), globs)
+
     return globs[fn_name]
 
 

src/cattrs/gen/typeddicts.py

@@ -225,21 +225,20 @@ def make_dict_unstructure_fn(
         ]
         script = "\n".join(total_lines)
 
-        fname = generate_unique_filename(
-            cl, "unstructure", reserve=_cattrs_use_linecache
-        )
-
-        eval(compile(script, fname, "exec"), globs)
-
-        fn = globs[fn_name]
+        fname = ""
         if _cattrs_use_linecache:
+            fname = generate_unique_filename(
+                cl, "unstructure", reserve=_cattrs_use_linecache
+            )
             linecache.cache[fname] = len(script), None, total_lines, fname
+
+        eval(compile(script, fname, "exec"), globs)
     finally:
         working_set.remove(cl)
         if not working_set:
             del already_generating.working_set
 
-    return fn
+    return globs[fn_name]
 
 
 def make_dict_structure_fn(
@@ -523,12 +522,13 @@ def make_dict_structure_fn(
         "  return res",
     ]
 
-    fname = generate_unique_filename(cl, "structure", reserve=_cattrs_use_linecache)
     script = "\n".join(total_lines)
-    eval(compile(script, fname, "exec"), globs)
+    fname = ""
     if _cattrs_use_linecache:
+        fname = generate_unique_filename(cl, "structure", reserve=_cattrs_use_linecache)
         linecache.cache[fname] = len(script), None, total_lines, fname
 
+    eval(compile(script, fname, "exec"), globs)
     return globs[fn_name]