From b019af6cc79f12e433932eaa56914116b0b41f4a Mon Sep 17 00:00:00 2001
From: shauryagangrade <288927048+shauryagangrade@users.noreply.github.com>
Date: Thu, 3 Sep 2026 22:52:56 +0530
Subject: [PATCH 1/3] fix: raise ValueError for unrecognized strategy names in
 strategy_features()

strategy_features() silently accepted any unrecognized strategy name (e.g.
a typo like 'in_procesing') by falling through to the bare 'return list(core)'
branch. This gave a wrong-but-plausible result with no error, making bugs
hard to trace.

Replace the catch-all return with an explicit check for the three known
core-only strategies, and raise ValueError for anything else. Add tests
covering both a typo'd strategy name and an empty string.

Fixes #418
---
 faircode/strategies.py   |  4 +++-
 tests/test_strategies.py | 10 ++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/faircode/strategies.py b/faircode/strategies.py
index 2ec9342..6e8662f 100644
--- a/faircode/strategies.py
+++ b/faircode/strategies.py
@@ -99,7 +99,9 @@ def strategy_features(strategy: str, core: list, proxies: list, protected: list)
         return list(dict.fromkeys(core + proxies + protected))
     if strategy == "unawareness":
         return list(dict.fromkeys(core + proxies))
-    return list(core)  # unawareness_proxy_removal, in_processing, post_processing
+    if strategy in ("unawareness_proxy_removal", "in_processing", "post_processing"):
+        return list(core)
+    raise ValueError(f"unknown strategy: {strategy!r}")
 
 
 def fit_in_processing(base_model, X_train, y_train, sensitive_train):
diff --git a/tests/test_strategies.py b/tests/test_strategies.py
index 58178e1..d89b721 100644
--- a/tests/test_strategies.py
+++ b/tests/test_strategies.py
@@ -65,6 +65,16 @@ def test_strategy_features_deduplicates_overlapping_names():
     assert set(cols) == {"a", "b", "c"}
 
 
+def test_strategy_features_raises_on_unknown_strategy():
+    with pytest.raises(ValueError, match="unknown strategy: 'in_procesing'"):
+        strategy_features("in_procesing", CORE, PROXIES, PROTECTED)
+
+
+def test_strategy_features_raises_on_empty_string():
+    with pytest.raises(ValueError, match="unknown strategy: ''"):
+        strategy_features("", CORE, PROXIES, PROTECTED)
+
+
 # ── encode_features ──────────────────────────────────────────────────────────
 def test_encode_features_passes_numeric_columns_through():
     df = pd.DataFrame({"age": [20.0, 30.0, 40.0]})

From 00183df396ed845a41c876d7ef7cb1b29a9f2d29 Mon Sep 17 00:00:00 2001
From: Yash Kewlani <86704881+yakew7@users.noreply.github.com>
Date: Thu, 3 Sep 2026 22:58:05 +0530
Subject: [PATCH 2/3] Fix strategy handling for unawareness_proxy_removal

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 faircode/strategies.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/faircode/strategies.py b/faircode/strategies.py
index 6e8662f..593ced1 100644
--- a/faircode/strategies.py
+++ b/faircode/strategies.py
@@ -99,8 +99,8 @@ def strategy_features(strategy: str, core: list, proxies: list, protected: list)
         return list(dict.fromkeys(core + proxies + protected))
     if strategy == "unawareness":
         return list(dict.fromkeys(core + proxies))
-    if strategy in ("unawareness_proxy_removal", "in_processing", "post_processing"):
-        return list(core)
+if strategy in ("unawareness_proxy_removal", "in_processing", "post_processing"):
+        return list(dict.fromkeys(core))
     raise ValueError(f"unknown strategy: {strategy!r}")
 
 

From 9e6b7cc8ff32ea8513f11d08f3580441763c40a3 Mon Sep 17 00:00:00 2001
From: Yash Kewlani <86704881+yakew7@users.noreply.github.com>
Date: Thu, 3 Sep 2026 23:02:45 +0530
Subject: [PATCH 3/3] Fix indentation for strategy condition check

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 faircode/strategies.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/faircode/strategies.py b/faircode/strategies.py
index 593ced1..c47b189 100644
--- a/faircode/strategies.py
+++ b/faircode/strategies.py
@@ -99,7 +99,7 @@ def strategy_features(strategy: str, core: list, proxies: list, protected: list)
         return list(dict.fromkeys(core + proxies + protected))
     if strategy == "unawareness":
         return list(dict.fromkeys(core + proxies))
-if strategy in ("unawareness_proxy_removal", "in_processing", "post_processing"):
+    if strategy in ("unawareness_proxy_removal", "in_processing", "post_processing"):
         return list(dict.fromkeys(core))
     raise ValueError(f"unknown strategy: {strategy!r}")