fix: only instantiate colored objects if color is not disabled (#634)

src/syrupy/terminal.py

@@ -13,30 +13,48 @@ def _is_color_disabled() -> bool:
     return any(map(get_env_value, DISABLE_COLOR_ENV_VARS))
 
 
+def _attr(color: Any) -> str:
+    if _is_color_disabled():
+        return ""
+    return colored.attr(color)
+
+
+def _fg(color: Any) -> str:
+    if _is_color_disabled():
+        return ""
+    return colored.fg(color)
+
+
+def _bg(color: Any) -> str:
+    if _is_color_disabled():
+        return ""
+    return colored.bg(color)
+
+
 def _stylize(text: Union[str, int], *args: Any) -> str:
     if _is_color_disabled():
         return str(text)
     return colored.stylize(text, *args)
 
 
 def reset(text: Union[str, int]) -> str:
-    return _stylize(text, colored.attr("reset"))
+    return _stylize(text, _attr("reset"))
 
 
 def red(text: Union[str, int]) -> str:
-    return _stylize(text, colored.fg("red"))
+    return _stylize(text, _fg("red"))
 
 
 def yellow(text: Union[str, int]) -> str:
-    return _stylize(text, colored.fg("yellow"))
+    return _stylize(text, _fg("yellow"))
 
 
 def green(text: Union[str, int]) -> str:
-    return _stylize(text, colored.fg("green"))
+    return _stylize(text, _fg("green"))
 
 
 def bold(text: Union[str, int]) -> str:
-    return _stylize(text, colored.attr("bold"))
+    return _stylize(text, _attr("bold"))
 
 
 def error_style(text: Union[str, int]) -> str:
@@ -52,20 +70,20 @@ def success_style(text: Union[str, int]) -> str:
 
 
 def snapshot_style(text: Union[str, int]) -> str:
-    return _stylize(text, colored.bg(225) + colored.fg(90))
+    return _stylize(text, _bg(225) + _fg(90))
 
 
 def snapshot_diff_style(text: Union[str, int]) -> str:
-    return _stylize(text, colored.bg(90) + colored.fg(225))
+    return _stylize(text, _bg(90) + _fg(225))
 
 
 def received_style(text: Union[str, int]) -> str:
-    return _stylize(text, colored.bg(195) + colored.fg(23))
+    return _stylize(text, _bg(195) + _fg(23))
 
 
 def received_diff_style(text: Union[str, int]) -> str:
-    return _stylize(text, colored.bg(23) + colored.fg(195))
+    return _stylize(text, _bg(23) + _fg(195))
 
 
 def context_style(text: Union[str, int]) -> str:
-    return _stylize(text, colored.attr("dim"))
+    return _stylize(text, _attr("dim"))

tests/syrupy/test_terminal.py

@@ -0,0 +1,58 @@
+from unittest.mock import (
+    NonCallableMock,
+    patch,
+)
+
+import pytest
+
+from syrupy.constants import DISABLE_COLOR_ENV_VAR
+from syrupy.terminal import (
+    bold,
+    context_style,
+    error_style,
+    green,
+    received_diff_style,
+    received_style,
+    red,
+    reset,
+    snapshot_diff_style,
+    snapshot_style,
+    success_style,
+    warning_style,
+    yellow,
+)
+
+
+def test_colors_off_does_not_call_colored():
+    """
+    Test that disabling colors prevents instantiating colored object.
+    Enables workarounds for when instantiating the colored object causes crashes,
+    see issue #633
+    """
+
+    with patch(
+        "syrupy.terminal.colored.colored.__init__", new_callable=NonCallableMock
+    ):
+        with patch.dict("os.environ", {DISABLE_COLOR_ENV_VAR: "true"}):
+            for method in (
+                reset,
+                red,
+                yellow,
+                green,
+                bold,
+                error_style,
+                warning_style,
+                success_style,
+                snapshot_style,
+                snapshot_diff_style,
+                received_style,
+                received_diff_style,
+                context_style,
+            ):
+                _ = method("foo")
+
+        # Prevent test from accidentally passing by patching wrong object
+        with pytest.raises(TypeError) as excinfo:
+            _ = red("foo")
+
+        assert "NonCallableMock" in str(excinfo.value)