Python: Add test for instances

Author: yoff

python/ql/test/experimental/meta/InlineInstanceTest.qll

@@ -0,0 +1,29 @@
+/**
+ * Defines a InlineExpectationsTest for class instances, that is,
+ * for any API::Node that is an instance of a class (e.g. `Flask`).
+ */
+
+import python
+import semmle.python.ApiGraphs
+import utils.test.InlineExpectationsTest
+private import semmle.python.dataflow.new.internal.PrintNode
+
+signature API::Node getInstanceSig();
+
+module MakeInlineInstanceTest<getInstanceSig/0 getInstance> {
+  private module InlineInstanceTest implements TestSig {
+    string getARelevantTag() { result = "instance" }
+
+    predicate hasActualResult(Location location, string element, string tag, string value) {
+      exists(location.getFile().getRelativePath()) and
+      exists(API::Node instance | instance = getInstance() |
+        location = instance.getLocation() and
+        element = prettyNode(instance.asSource()) and
+        value = "" and
+        tag = "instance"
+      )
+    }
+  }
+
+  import MakeTest<InlineInstanceTest>
+}

python/ql/test/library-tests/frameworks/flask/InlineInstanceTest.expected

@@ -0,0 +1,8 @@
+import python
+import semmle.python.frameworks.Flask
+import semmle.python.ApiGraphs
+import experimental.meta.InlineInstanceTest
+
+API::Node getInstance() { result = Flask::FlaskApp::instance() }
+
+import MakeInlineInstanceTest<getInstance/0>

python/ql/test/library-tests/frameworks/flask/InlineInstanceTest.ql

@@ -1,7 +1,7 @@
 import flask
 
 from flask import Flask, request, make_response
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 @app.route("/")  # $ routeSetup="/"
 def hello_world():  # $ requestHandler

python/ql/test/library-tests/frameworks/flask/old_test.py

@@ -3,7 +3,7 @@
 from flask import Flask, make_response, jsonify, Response, request, redirect
 from werkzeug.datastructures import Headers
 
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 
 @app.route("/html1")  # $ routeSetup="/html1"

python/ql/test/library-tests/frameworks/flask/response_test.py

@@ -1,7 +1,7 @@
 import flask
 
 from flask import Flask, make_response
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 
 SOME_ROUTE = "/some/route"

python/ql/test/library-tests/frameworks/flask/routing_test.py

@@ -1,5 +1,5 @@
 from flask import Flask, request
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 @app.route("/save-uploaded-file")  # $ routeSetup="/save-uploaded-file"
 def test_taint():  # $ requestHandler

python/ql/test/library-tests/frameworks/flask/save_uploaded_file.py

@@ -1,5 +1,5 @@
 from flask import Flask, request, render_template_string, stream_template_string
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 @app.route("/test_taint/<name>/<int:number>")  # $ routeSetup="/test_taint/<name>/<int:number>"
 def test_taint(name = "World!", number="0", foo="foo"):  # $ requestHandler routedParameter=name routedParameter=number

python/ql/test/library-tests/frameworks/flask/taint_test.py

@@ -1,5 +1,5 @@
 from flask import Flask, Response, stream_with_context, render_template_string, stream_template_string
-app = Flask(__name__)
+app = Flask(__name__) # $ instance
 
 @app.route("/a")  # $ routeSetup="/a"
 def a():  # $ requestHandler