SetPythonPath prints sys.path on failure

tminka · tminka · commit fac1347fc719 · 2021-01-03T16:52:59.000Z
diff --git a/src/embed_tests/TestPythonEngineProperties.cs b/src/embed_tests/TestPythonEngineProperties.cs
@@ -185,24 +185,24 @@ public void SetPythonPath()
 
             using (Py.GIL())
             {
+                // path should not be set to PythonEngine.PythonPath here.
+                // PythonEngine.PythonPath gets the default module search path, not the full search path.
+                // The list sys.path is initialized with this value on interpreter startup;
+                // it can be (and usually is) modified later to change the search path for loading modules.
+                // See https://docs.python.org/3/c-api/init.html#c.Py_GetPath
+                // After PythonPath is set, then PythonEngine.PythonPath will correctly return the full search path. 
+
+                string[] paths = Py.Import("sys").GetAttr("path").As<string[]>();
+                path = string.Join(System.IO.Path.PathSeparator.ToString(), paths);
+
                 try
                 {
                     Py.Import(moduleName);
                 }
                 catch (PythonException ex)
                 {
-                    throw new Exception($"Py.Import(\"{moduleName}\") failed before setting PythonEngine.PythonPath", ex);
+                    throw new Exception($"Py.Import(\"{moduleName}\") failed before setting PythonEngine.PythonPath.  sys.path={path}", ex);
                 }
-
-                string[] paths = Py.Import("sys").GetAttr("path").As<string[]>();
-                path = string.Join(System.IO.Path.PathSeparator.ToString(), paths);
-
-                // path should not be set to PythonEngine.PythonPath here.
-                // PythonEngine.PythonPath gets the default module search path, not the full search path.
-                // The list sys.path is initialized with this value on interpreter startup;
-                // it can be (and usually is) modified later to change the search path for loading modules.
-                // See https://docs.python.org/3/c-api/init.html#c.Py_GetPath
-                // After PythonPath is set, then PythonEngine.PythonPath will correctly return the full search path. 
             }
 
             PythonEngine.PythonPath = path;

Original file line number	Diff line number	Diff line change
`@@ -185,24 +185,24 @@ public void SetPythonPath()`
`185`	`185`
`186`	`186`	`using (Py.GIL())`
`187`	`187`	`{`
	`188`	`+ // path should not be set to PythonEngine.PythonPath here.`
	`189`	`+ // PythonEngine.PythonPath gets the default module search path, not the full search path.`
	`190`	`+ // The list sys.path is initialized with this value on interpreter startup;`
	`191`	`+ // it can be (and usually is) modified later to change the search path for loading modules.`
	`192`	`+ // See https://docs.python.org/3/c-api/init.html#c.Py_GetPath`
	`193`	`+ // After PythonPath is set, then PythonEngine.PythonPath will correctly return the full search path.`
	`194`	`+`
	`195`	`+ string[] paths = Py.Import("sys").GetAttr("path").As<string[]>();`
	`196`	`+ path = string.Join(System.IO.Path.PathSeparator.ToString(), paths);`
	`197`	`+`
`188`	`198`	`try`
`189`	`199`	`{`
`190`	`200`	`Py.Import(moduleName);`
`191`	`201`	`}`
`192`	`202`	`catch (PythonException ex)`
`193`	`203`	`{`
`194`		`- throw new Exception($"Py.Import(\"{moduleName}\") failed before setting PythonEngine.PythonPath", ex);`
	`204`	`+ throw new Exception($"Py.Import(\"{moduleName}\") failed before setting PythonEngine.PythonPath. sys.path={path}", ex);`
`195`	`205`	`}`
`196`		`-`
`197`		`- string[] paths = Py.Import("sys").GetAttr("path").As<string[]>();`
`198`		`- path = string.Join(System.IO.Path.PathSeparator.ToString(), paths);`
`199`		`-`
`200`		`- // path should not be set to PythonEngine.PythonPath here.`
`201`		`- // PythonEngine.PythonPath gets the default module search path, not the full search path.`
`202`		`- // The list sys.path is initialized with this value on interpreter startup;`
`203`		`- // it can be (and usually is) modified later to change the search path for loading modules.`
`204`		`- // See https://docs.python.org/3/c-api/init.html#c.Py_GetPath`
`205`		`- // After PythonPath is set, then PythonEngine.PythonPath will correctly return the full search path.`
`206`	`206`	`}`
`207`	`207`
`208`	`208`	`PythonEngine.PythonPath = path;`