Revert "Merge pull request #21941 from hvitved/python/content-approx"

This reverts commit f5919875b7, reversing
changes made to 8d456df26f.

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll

@@ -1249,65 +1249,12 @@ predicate allowParameterReturnInSelf(ParameterNode p) {
   )
 }
 
-bindingset[s]
-private string getFirstChar(string s) {
-  result =
-    min(int i, string c |
-      c = s.charAt(i) and c != "_"
-      or
-      c = "" and i = s.length()
-    |
-      c order by i
-    )
-}
-
-private string getAttributeContentFirstChar(AttributeContent ac) {
-  result = getFirstChar(ac.getAttribute())
-}
-
-private string getDictionaryElementContentKeyFirstChar(DictionaryElementContent dec) {
-  result = getFirstChar(dec.getKey())
-}
-
-private newtype TContentApprox =
-  TListElementContentApprox() or
-  TSetElementContentApprox() or
-  TTupleElementContentApprox() or
-  TDictionaryElementContentApprox(string first) {
-    first = "" // for `TDictionaryElementAnyContent`
-    or
-    first = getDictionaryElementContentKeyFirstChar(_)
-  } or
-  TAttributeContentApprox(string first) { first = getAttributeContentFirstChar(_) } or
-  TCapturedVariableContentApprox()
-
 /** An approximated `Content`. */
-class ContentApprox extends TContentApprox {
-  /** Gets a textual representation of this element. */
-  string toString() { result = "" }
-}
+class ContentApprox = Unit;
 
 /** Gets an approximated value for content `c`. */
-ContentApprox getContentApprox(Content c) {
-  c = TListElementContent() and
-  result = TListElementContentApprox()
-  or
-  c = TSetElementContent() and
-  result = TSetElementContentApprox()
-  or
-  c = TTupleElementContent(_) and
-  result = TTupleElementContentApprox()
-  or
-  result = TDictionaryElementContentApprox(getDictionaryElementContentKeyFirstChar(c))
-  or
-  c = TDictionaryElementAnyContent() and
-  result = TDictionaryElementContentApprox("")
-  or
-  result = TAttributeContentApprox(getAttributeContentFirstChar(c))
-  or
-  c = TCapturedVariableContent(_) and
-  result = TCapturedVariableContentApprox()
-}
+pragma[inline]
+ContentApprox getContentApprox(Content c) { any() }
 
 /** Helper for `.getEnclosingCallable`. */
 DataFlowCallable getCallableScope(Scope s) {