Merge pull request #4448 from RasmusWL/python-simplify-import-modeling

Python: simplify import modeling

python/ql/src/experimental/dataflow/internal/DataFlowUtil.qll

@@ -36,10 +36,8 @@ predicate localFlow(Node source, Node sink) { localFlowStep*(source, sink) }
  *   Example: If `mypkg/__init__.py` contains `foo = 42`, then `from mypkg import foo` will not import the module
  *   `mypkg/foo.py` but the variable `foo` containing `42` -- however, `import mypkg.foo` will always cause `mypkg.foo`
  *   to refer to the module.
- *
- * Also see `DataFlow::importMember`
  */
-Node importModule(string name) {
+Node importNode(string name) {
   exists(Variable var, Import imp, Alias alias |
     alias = imp.getAName() and
     alias.getAsname() = var.getAStore() and
@@ -72,20 +70,3 @@ Node importModule(string name) {
   // reference to `foo.bar`, as desired.
   result.asCfgNode().getNode() = any(ImportExpr i | i.getAnImportedModuleName() = name)
 }
-
-/**
- * Gets a EssaNode that holds the value imported by using fully qualified name in
- *`from <moduleName> import <memberName>`.
- *
- * Also see `DataFlow::importModule`.
- */
-EssaNode importMember(string moduleName, string memberName) {
-  exists(Variable var, Import imp, Alias alias, ImportMember member |
-    alias = imp.getAName() and
-    member = alias.getValue() and
-    moduleName = member.getModule().(ImportExpr).getImportedModuleName() and
-    memberName = member.getName() and
-    alias.getAsname() = var.getAStore() and
-    result.getVar().(AssignmentDefinition).getSourceVariable() = var
-  )
-}

python/ql/src/experimental/semmle/python/frameworks/Flask.qll

@@ -15,7 +15,7 @@ private module Flask {
   /** Gets a reference to the `flask` module. */
   DataFlow::Node flask(DataFlow::TypeTracker t) {
     t.start() and
-    result = DataFlow::importModule("flask")
+    result = DataFlow::importNode("flask")
     or
     exists(DataFlow::TypeTracker t2 | result = flask(t2).track(t2, t))
   }
@@ -27,7 +27,7 @@ private module Flask {
     /** Gets a reference to the `flask.request` object. */
     DataFlow::Node request(DataFlow::TypeTracker t) {
       t.start() and
-      result = DataFlow::importMember("flask", "request")
+      result = DataFlow::importNode("flask.request")
       or
       t.startInAttr("request") and
       result = flask()

python/ql/src/experimental/semmle/python/frameworks/Stdlib.qll

@@ -17,7 +17,7 @@ private module Stdlib {
   /** Gets a reference to the `os` module. */
   private DataFlow::Node os(DataFlow::TypeTracker t) {
     t.start() and
-    result = DataFlow::importModule("os")
+    result = DataFlow::importNode("os")
     or
     exists(DataFlow::TypeTracker t2 | result = os(t2).track(t2, t))
   }
@@ -42,10 +42,10 @@ private module Stdlib {
           "path"] and
     (
       t.start() and
-      result = DataFlow::importMember("os", attr_name)
+      result = DataFlow::importNode("os." + attr_name)
       or
       t.startInAttr(attr_name) and
-      result = DataFlow::importModule("os")
+      result = DataFlow::importNode("os")
     )
     or
     // Due to bad performance when using normal setup with `os_attr(t2, attr_name).track(t2, t)`
@@ -85,7 +85,7 @@ private module Stdlib {
       /** Gets a reference to the `os.path.join` function. */
       private DataFlow::Node join(DataFlow::TypeTracker t) {
         t.start() and
-        result = DataFlow::importMember("os.path", "join")
+        result = DataFlow::importNode("os.path.join")
         or
         t.startInAttr("join") and
         result = os::path()
@@ -190,7 +190,7 @@ private module Stdlib {
   /** Gets a reference to the `subprocess` module. */
   private DataFlow::Node subprocess(DataFlow::TypeTracker t) {
     t.start() and
-    result = DataFlow::importModule("subprocess")
+    result = DataFlow::importNode("subprocess")
     or
     exists(DataFlow::TypeTracker t2 | result = subprocess(t2).track(t2, t))
   }
@@ -208,10 +208,10 @@ private module Stdlib {
     attr_name in ["Popen", "call", "check_call", "check_output", "run"] and
     (
       t.start() and
-      result = DataFlow::importMember("subprocess", attr_name)
+      result = DataFlow::importNode("subprocess." + attr_name)
       or
       t.startInAttr(attr_name) and
-      result = DataFlow::importModule("subprocess")
+      result = subprocess()
     )
     or
     // Due to bad performance when using normal setup with `subprocess_attr(t2, attr_name).track(t2, t)`