bugfix:

- newly assigned variables are only written into the flags DataFrame
- if we used such a variable in a dsl function down the line, the lookup failed

saqc/core/evaluator/evaluator.py

@@ -15,10 +15,10 @@ from saqc.core.evaluator.checker import ConfigChecker
 from saqc.core.evaluator.transformer import ConfigTransformer
 
 
-def _dslIsFlagged(flagger, data, flag=None, comparator=None):
+def _dslIsFlagged(flagger, field, flag=None, comparator=None):
     if comparator is None:
-        return flagger.isFlagged(data.name, flag=flag)
-    return flagger.isFlagged(data.name, flag=flag, comparator=comparator)
+        return flagger.isFlagged(field, flag=flag)
+    return flagger.isFlagged(field, flag=flag, comparator=comparator)
 
 
 def initLocalEnv(data: pd.DataFrame, field: str, flagger: BaseFlagger, nodata: float) -> Dict[str, Any]:
@@ -26,7 +26,6 @@ def initLocalEnv(data: pd.DataFrame, field: str, flagger: BaseFlagger, nodata: f
     return {
         "data": data,
         "field": field,
-        "this": field,
         "flagger": flagger,
         "NAN": np.nan,
         "NODATA": nodata,
@@ -42,7 +41,11 @@ def initLocalEnv(data: pd.DataFrame, field: str, flagger: BaseFlagger, nodata: f
         "sum": np.nansum,
         "std": np.nanstd,
         "len": len,
-        "variables": set(data.columns.tolist() + flagger.getFlags().columns.tolist()),
+        # NOTE:
+        # the following pairs are only needed for the tree transformation
+        "nolookup": set(["isflagged"]), # no variable lookup for flagger based functions,
+        "variables": set(flagger.getFlags().columns.tolist()),
+        "this": field,
     }
 
 

saqc/core/evaluator/transformer.py

@@ -2,17 +2,31 @@
 # -*- coding: utf-8 -*-
 
 import ast
-from saqc.core.config import Params
+
 from typing import Dict, Any
+from contextlib import contextmanager
+
+from saqc.core.config import Params
 
 
 class DslTransformer(ast.NodeTransformer):
     def __init__(self, environment: Dict[str, Any]):
         self.environment = environment
         self.arguments = set()
+        self.lookup = True
+
+    @contextmanager
+    def doLookup(self, value):
+        self.lookup = value
+        yield
+        self.lookup = True
 
     def visit_Call(self, node):
-        return ast.Call(func=node.func, args=[self.visit(arg) for arg in node.args], keywords=[])
+        with self.doLookup(node.func.id not in self.environment["nolookup"]):
+            node = self.generic_visit(
+                ast.Call(func=node.func, args=node.args, keywords=[])
+            )
+        return node
 
     def visit_Name(self, node):
         name = node.id
@@ -21,10 +35,13 @@ class DslTransformer(ast.NodeTransformer):
             name = self.environment["field"]
 
         if name in self.environment["variables"]:
-            value = ast.Constant(value=name)
-            node = ast.Subscript(
-                value=ast.Name(id="data", ctx=ast.Load()), slice=ast.Index(value=value), ctx=ast.Load(),
-            )
+            if self.lookup:
+                value = ast.Constant(value=name)
+                node = ast.Subscript(
+                    value=ast.Name(id="data", ctx=ast.Load()), slice=ast.Index(value=value), ctx=ast.Load(),
+                )
+            else:
+                node = ast.Str(s=name)
 
         self.arguments.add(name)
         return node