Add concepts tests + some fixes

python/ql/lib/semmle/python/frameworks/Flask.qll

@@ -722,10 +722,13 @@ module Flask {
     }
   }
 
-  /** A call to `flask.render_template_string` as a template construction sink. */
+  /** A call to `flask.render_template_string` or `flask.stream_template_string` as a template construction sink. */
   private class FlaskTemplateConstruction extends TemplateConstruction::Range, API::CallNode {
     FlaskTemplateConstruction() {
-      this = API::moduleImport("flask").getMember("render_template_string").getACall()
+      this =
+        API::moduleImport("flask")
+            .getMember(["render_template_string", "stream_template_string"])
+            .getACall()
     }
 
     override DataFlow::Node getSourceArg() { result = this.getArg(0) }

python/ql/lib/semmle/python/frameworks/Genshi.qll

@@ -21,7 +21,7 @@ module Genshi {
         API::moduleImport("genshi")
             .getMember("template")
             .getMember("text")
-            .getMember(["NewTextTemplate", "OldTextTemplate"])
+            .getMember(["NewTextTemplate", "OldTextTemplate", "TextTemplate"])
             .getACall()
     }
 

python/ql/lib/semmle/python/frameworks/Jinja2.qll

@@ -24,6 +24,7 @@ module Jinja2 {
     override DataFlow::Node getSourceArg() { result = this.getArg(0) }
   }
 
+  /** Definitions for modeling jinja `Environment`s. */
   module EnvironmentClass {
     /** Gets a reference to the `jinja2.Environment` class. */
     API::Node classRef() {