Ruby: Move TestFile to modeling Util module

The TestFile class in the ModelEditor module is more accurate than the
existing RelevantFile class in the Util module, so this moves the
TestFile class to Util and redefines RelevantFile in terms of the
TestFile.

Author: koesie10

ruby/ql/src/queries/modeling/internal/Util.qll

@@ -5,13 +5,23 @@
 private import ruby
 private import codeql.ruby.ApiGraphs
 
+/**
+ * A file that probably contains tests.
+ */
+class TestFile extends File {
+  TestFile() {
+    this.getRelativePath().regexpMatch(".*(test|spec|examples).+") and
+    not this.getAbsolutePath().matches("%/ql/test/%") // allows our test cases to work
+  }
+}
+
 /**
  * A file that is relevant in the context of library modeling.
  *
  * In practice, this means a file that is not part of test code.
  */
 class RelevantFile extends File {
-  RelevantFile() { not this.getRelativePath().regexpMatch(".*/?test(case)?s?/.*") }
+  RelevantFile() { not this instanceof TestFile }
 }
 
 /**

ruby/ql/src/utils/modeleditor/ModelEditor.qll

@@ -9,11 +9,6 @@ private import codeql.ruby.frameworks.data.ModelsAsData
 private import codeql.ruby.frameworks.data.internal.ApiGraphModelsExtensions
 private import queries.modeling.internal.Util as Util
 
-/** Holds if the given callable is not worth supporting. */
-private predicate isUninteresting(DataFlow::MethodNode c) {
-  c.getLocation().getFile() instanceof TestFile
-}
-
 private predicate gemFileStep(Gem::GemSpec gem, Folder folder, int n) {
   n = 0 and folder.getAFile() = gem.(File)
   or
@@ -63,7 +58,7 @@ abstract class Endpoint instanceof DataFlow::Node {
 class MethodEndpoint extends Endpoint instanceof DataFlow::MethodNode {
   MethodEndpoint() {
     this.isPublic() and
-    not isUninteresting(this)
+    this.(DataFlow::MethodNode).getLocation().getFile() instanceof Util::RelevantFile
   }
 
   DataFlow::MethodNode getNode() { result = this }
@@ -144,19 +139,12 @@ class MethodEndpoint extends Endpoint instanceof DataFlow::MethodNode {
 }
 
 string methodClassification(Call method) {
-  method.getFile() instanceof TestFile and result = "test"
+  method.getFile() instanceof Util::TestFile and result = "test"
   or
-  not method.getFile() instanceof TestFile and
+  not method.getFile() instanceof Util::TestFile and
   result = "source"
 }
 
-class TestFile extends File {
-  TestFile() {
-    this.getRelativePath().regexpMatch(".*(test|spec|examples).+") and
-    not this.getAbsolutePath().matches("%/ql/test/%") // allows our test cases to work
-  }
-}
-
 /**
  * A callable where there exists a MaD sink model that applies to it.
  */
@@ -222,7 +210,7 @@ class ModuleEndpoint extends Endpoint {
         n order by loc.getFile().getAbsolutePath(), loc.getStartLine(), loc.getStartColumn()
       ) and
     not moduleNode.(Module).isBuiltin() and
-    not moduleNode.getLocation().getFile() instanceof TestFile
+    moduleNode.getLocation().getFile() instanceof Util::RelevantFile
   }
 
   DataFlow::ModuleNode getNode() { result = moduleNode }