Python: more logic adjustment

yoff · yoff · commit 8a81d42e6fad · 2021-10-26T10:57:27.000+02:00
Not sure why the missing result is missing. There is
and edge with label `getAwaited` from `pkg.async_func` on line 22
to `coro` on line 23.
diff --git a/python/ql/lib/semmle/python/ApiGraphs.qll b/python/ql/lib/semmle/python/ApiGraphs.qll
@@ -494,26 +494,26 @@ module API {
       // - `awaitedValue` is `x`
       // - `result` is `await x`
       exists(Await await |
-        result.asExpr() = await and
-        await.getValue() = awaitedValue.asExpr()
+        await.getValue() = awaitedValue.asExpr() and
+        result.asExpr() = await
       )
       or
       // `async for x in l`
       // - `awaitedValue` is `l`
-      // - `result` is `l` (should perhaps be `x`, but that should really be a read)
+      // - `result` is `l` (`x` is behind a read step)
       exists(AsyncFor asyncFor |
-        result.asExpr() = asyncFor.getIter() and
         // To consider `x` the result of awaiting, we would use asyncFor.getTarget() = awaitedValue.asExpr(),
         // but that is behind a read step rather than a flow step.
-        asyncFor.getIter() = awaitedValue.asExpr()
+        asyncFor.getIter() = awaitedValue.asExpr() and
+        result.asExpr() = asyncFor.getIter()
       )
       or
       // `async with x as y`
       // - `awaitedValue` is `x`
       // - `result` is `x` and `y` if it exists
       exists(AsyncWith asyncWith |
-        result.asExpr() = asyncWith.getContextExpr() and
-        awaitedValue.asExpr() in [
+        awaitedValue.asExpr() = asyncWith.getContextExpr() and
+        result.asExpr() in [
             // `x`
             asyncWith.getContextExpr(),
             // `y`, if it exists
diff --git a/python/ql/lib/semmle/python/frameworks/Asyncpg.qll b/python/ql/lib/semmle/python/frameworks/Asyncpg.qll
@@ -75,26 +75,26 @@ private module Asyncpg {
     // - `awaitedValue` is `x`
     // - `result` is `await x`
     exists(Await await |
-      result.asExpr() = await and
-      await.getValue() = awaitedValue.asExpr()
+      await.getValue() = awaitedValue.asExpr() and
+      result.asExpr() = await
     )
     or
     // `async for x in l`
     // - `awaitedValue` is local source of `l`
     // - `result` is `l`
     exists(AsyncFor asyncFor, DataFlow::Node awaited |
-      result.asExpr() = asyncFor.getIter() and
       asyncFor.getIter() = awaited.asExpr() and
-      awaited.getALocalSource() = awaitedValue
+      awaited.getALocalSource() = awaitedValue and
+      result.asExpr() = asyncFor.getIter()
     )
     or
     // `async with x as y`
     // - `awaitedValue` is local source of `x`
     // - `result` is `x` and `y`
     exists(AsyncWith asyncWith, DataFlow::Node awaited |
-      result.asExpr() = asyncWith.getContextExpr() and
-      awaited.asExpr() in [asyncWith.getContextExpr(), asyncWith.getOptionalVars()] and
-      awaited.getALocalSource() = awaitedValue
+      awaited.asExpr() = asyncWith.getContextExpr() and
+      awaited.getALocalSource() = awaitedValue and
+      result.asExpr() in [asyncWith.getContextExpr(), asyncWith.getOptionalVars()]
     )
   }
 
diff --git a/python/ql/test/experimental/dataflow/ApiGraphs/async_test.py b/python/ql/test/experimental/dataflow/ApiGraphs/async_test.py
@@ -12,7 +12,7 @@ async def bar():
     return result # $ use=moduleImport("pkg").getMember("async_func").getReturn().getAwaited() awaited=moduleImport("pkg").getMember("async_func").getReturn()
 
 async def test_async_with():
-    async with pkg.async_func() as result: # $ use=moduleImport("pkg").getMember("async_func").getReturn() awaited=moduleImport("pkg").getMember("async_func").getReturn()
+    async with pkg.async_func() as result: # $ use=moduleImport("pkg").getMember("async_func").getReturn().getAwaited() awaited=moduleImport("pkg").getMember("async_func").getReturn()
         return result # $ use=moduleImport("pkg").getMember("async_func").getReturn() awaited=moduleImport("pkg").getMember("async_func").getReturn()
 
 async def test_async_for():
